Identity Management Guide
Managing Identity and Authorization Policies for Linux-Based Infrastructures
Abstract
Chapter 1. Introduction to Identity Management
1.1. IdM v. LDAP: A More Focused Type of Service
1.1.1. A Working Definition for Identity Management
- Create a Linux-based and Linux-controlled domain. Both IdM servers and IdM clients are Linux or Unix machines. While IdM can synchronize data with an Active Directory domain to allow integration with Windows servers, it is not an administrative tool for Windows machines and it does not support Windows clients. Identity Management is a management tool for Linux domains.
- Centralize identity management and identity policies.
- Build on existing, native Linux applications and protocols. While IdM has its own processes and configuration, its underlying technologies are familiar and trusted by Linux administrators and are well established on Linux systems.
1.1.2. Contrasting Identity Management with a Standard LDAP Directory
389 Directory Server | Identity Management | |
---|---|---|
Use | General purpose | Single domain, focused on identity management |
Flexibility | Highly-customizable | Limitations to focus on identity and authentication |
Schema | Default LDAP schema | Optimized, special schema for identity management |
Directory Tree | Standard and flexible hierarchy | Flat tree with a fixed hierarchy |
Authentication | LDAP | Kerberos or Kerberos and LDAP |
Active Directory Synchronization | Bi-directional | Unidirectional, Active Directory to Identity Management |
Password Policies | LDAP-based | Kerberos-based |
User Tools | Java Console and standard LDAP utilities | Web-based UI and special Python command-line tools |
1.2. Bringing Linux Services Together
Figure 1.1. The IdM Server: Unifying Services
1.2.1. Authentication: Kerberos KDC
Note
1.2.2. Data Storage: 389 Directory Server
1.2.3. Authentication: Dogtag Certificate System
1.2.4. Server/Client Discovery: DNS
Note
1.2.5. Management: SSSD
true
, false
, and preserve
values for the case_sensitive
option. When the preserve
value is enabled, the input matches regardless of the case, but the output is always the same case as on the server; SSSD preserves the case for the UID field as it is configured.
1.2.6. Management: NTP
1.3. Relationships Between Servers and Clients
1.3.1. About IdM Servers and Replicas
Note
Figure 1.2. Server and Replica Interactions
Note
1.3.2. About IdM Clients
Figure 1.3. Server and Client Interactions
- Store IdM information when the machine is offline.
- Keep information active beyond its normal timeout period if the client cannot access the central server. The cache is persistent even after rebooting the machine.
- Reduce the round-trip time of requests by checking information locally before looking at the server.
- Identity information (about users, machines, and groups) is stored in the LDB database, which uses the same syntax as an LDAP directory. This identity information is originally stored in the IdM server's 389 Directory Server instance. Because this information changes frequently and is referenced frequently, it is important to be able to call the more current information quickly, which is possible using an LDB database on the client and the Directory Server on the server.
- Policy information is more static than identity information, and it can include configuration for SELinux or sudo. These policies are set globally on the server and then are propagated to the clients. On the client, the policy information is stored in the filesystem in XML files which can be downloaded and converted into a native file for whatever service is being managed.
Figure 1.4. Interactions Between IdM Services
- SSSD provides the user authentication for the machine and enforces host-based access control rules.
certmonger
monitors and renews the certificates on the client. It can request new certificates for the services on the system, including virtual machines.
certmonger
are configured to connect to the IdM server and the required Kerberos keytab and host certificates are created. (The host certificate is not used directly by IdM; it may be used by other services, such as a web server.)
Part I. Installing Identity Management; Servers and Services
Chapter 2. Prerequisites for Installation
2.1. Supported Server Platforms
- Red Hat Enterprise Linux 6 i386
- Red Hat Enterprise Linux 6 x86_64
2.2. Hardware Recommendations
- For 10,000 users and 100 groups, have at least 2GB of RAM and 1GB swap space.
- For 100,000 users and 50,000 groups, have at least 16GB of RAM and 4GB of swap space.
Note
2.3. Software Requirements
- Kerberos 1.10. This is installed as a dependency if it is not already installed.
- The bind and bind-dyndb-ldap packages for DNS. The bind package is installed as a dependency if it is not already available; however, the bind-dyndb-ldap package must be explicitly installed first or attempting to configure an IdM server with DNS support will fail.
Important
mod_nss
module. You can ensure that by following these steps:
- Edit the
/etc/httpd/conf.d/nss.conf
file and set theNSSProtocol
parameter toTLSv1.0
(for backward compatibility) andTLSv1.1
.NSSProtocol TLSv1.0,TLSv1.1
- Restart the
httpd
service.# service httpd restart
2.4. System Prerequisites
2.4.1. DNS Records
ifconfig
and dig
.
- Obtain the hostname.
[root@server ~]# hostname server.example.com
- Get the IP address. In this example, the returned IP address is
196.2.3.4
.[root@server !]# ifconfig eth0 eth0 Link encap:Ethernet HWaddr 52:54:01:4C:E1:2C
inet addr:196.2.3.4
Bcast:196.9.8.7 Mask:255.255.255.255 inet6 addr: 2620:52:0:102f:5054:1ff:fe4c:e12c/64 Scope:Global inet6 addr: fe80::5054:1ff:fe4c:e12c/64 Scope:Link ... - Verify that forward DNS is properly configured by using
dig
to query the hostname and check what IP address is returned. In this example, the expected IP address is196.2.3.4
.[root@server ~]# dig server.example.com ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.17.rc1.el6 <<>> server.example.com ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 56680 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 7, ADDITIONAL: 12 ;; QUESTION SECTION:
;server.example.com. IN A
;; ANSWER SECTION:server.example.com. 2946 IN A 196.2.3.4
- Verify the reverse DNS configuration using
dig
with the-t ptr
to query the PTR records (reverse records) for the address. This is the IP address in reverse order, with.in-addr.arpa.
appended to the address. This should resolve to the hostname,server.example.com.
in this example.[root@server ~]# dig -t ptr 4.3.2.196.in-addr.arpa. ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.17.rc1.el6 <<>> -t ptr 241.40.16.10.in-addr.arpa ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 57899 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 7, ADDITIONAL: 10 ;; QUESTION SECTION:
;4.3.2.196.in-addr.arpa. IN PTR
;; ANSWER SECTION:4.3.2.196.in-addr.arpa. 21600 IN PTR server.example.com.
Note
2.4.2. Hostname and IP Address Requirements
- The hostname must be a fully-qualified domain name. For example,
ipaserver.example.com
.Important
This must be a valid DNS name, which means only numbers, alphabetic characters, and hyphens (-) are allowed. Other characters, like underscores, in the hostname will cause DNS failures. - The hostname must be all lower-case.
- The server's A record must be set and resolve to its public IP address.The fully-qualified domain name cannot resolve to the loopback address. It must resolve to the machine's public IP address, not to
127.0.0.1
. The output of thehostname
command cannot belocalhost
orlocalhost6
.The A adn PTR records do not need to match for the server. - The server's hostname and IP address must be in its own
/etc/hosts
file. The fully-qualified domain name for the IdM server must be listed in thehosts
file before any aliases.Note
A misconfigured file can prevent the IdM command-line tools from functioning correctly and can prevent the IdM web interface from connecting to the IdM server.Additionally, the hostname cannot be part of the localhost entry.For example, this lists the IPv4 and IPv6 localhost entries for the host (properly), then the IdM server IP address and hostname as the first entry.127.0.0.1 localhost.localdomain localhost ::1 localhost6.localdomain6 localhost6 192.168.1.1 ipaserver.example.com ipaserver
- It is recommended that a separate DNS domain be allocated for the IdM server to manage. While not required (clients from other domains can still be enrolled in the IdM domain), this is a convenience for overall DNS management.
2.4.3. Directory Server
2.4.4. System Files
2.4.5. System Ports
iptables
utility to list the available ports or the nc
, telnet
, or nmap
utilities to connect to a port or run a port scan.
[root@server ~]# iptables -A INPUT -p tcp --dport 389 -j ACCEPT
Service | Ports | Type |
---|---|---|
HTTP/HTTPS | 80, 443 | TCP |
LDAP/LDAPS | 389, 636 | TCP |
Kerberos | 88, 464 | TCP and UDP |
DNS | 53 | TCP and UDP |
NTP | 123 | UDP |
Dogtag Certificate System - LDAP | 7389 | TCP |
2.4.6. NTP
--no-ntp
option when the IdM server is configured to prevent an NTP server from being installed.
2.4.7. NSCD
nscd
in an IdM deployment. The nscd
service is extremely useful for reducing the load on the server, and for making clients more responsive, but there can be problems when a system is also using SSSD, which performs its own caching.
nscd
caches authentication and identity information for all services that perform queries through nsswitch, including getent
. Because nscd
performs both positive and negative caching, if a request determines that a specific IdM user does not exist, it caches this as a negative response. Values stored in the cache remain until the cache expires, regardless of any changes that may occur on the server. The results of such caching is that new users and memberships may not be visible, and users and memberships that have been removed may still be visible.
nscd
altogether. Alternatively, use a shorter cache time by resetting the time-to-live caching values in the /etc/nscd.conf
file:
positive-time-to-live group 3600 negative-time-to-live group 60 positive-time-to-live hosts 3600 negative-time-to-live hosts 20
2.4.8. Networking
network
service to manage the networking requirements in an IdM environment and disable the NetworkManager service.
- Boot the machine into single-user mode.
- Disable off the NetworkManager service in the start list and stop the NetworkManager service.
[root@server ~]# chkconfig NetworkManager off; service NetworkManager stop
- If
NetworkManagerDispatcher
is installed, ensure that it is stopped and disabled:[root@server ~]# chkconfig NetworkManagerDispatcher off; service NetworkManagerDispatcher stop
- Then, make sure that the
network
service is properly started.[root@server ~]# chkconfig network on; service network start
- Ensure that static networking is correctly configured.
- Restart the system.
Chapter 3. Installing an IdM Server
3.1. Installing the IdM Server Packages
ipa-server
. If the IdM server will also manage a DNS server, then it requires two additional packages to set up the DNS.
yum
command:
[root@server ~]# yum install ipa-server bind bind-dyndb-ldap
ipa-server
also installs a large number of dependencies, such as 389-ds-base for the LDAP service and krb5-server for the Kerberos service, along with IdM tools.
ipa-server-install
command. The options for configuring the new server instance are described in Section 3.2, “About ipa-server-install”.
3.2. About ipa-server-install
ipa-server-install
script. This script can accept user-defined settings for services, like DNS and Kerberos, that are used by the IdM instance, or it can supply predefined values for minimal input from the administrator.
- The network time daemon (ntpd)
- A 389 Directory Server instance
- A Kerberos key distribution center (KDC)
- Apache (httpd)
- An updated SELinux targeted policy
- The Active Directory WinSync plug-in
- A certificate authority
- Optional. A domain name service (DNS) server
ipa-server-install
script.
Note
ipa-server-install
can be run without any options, so that it prompts for the required information, it has numerous arguments which allow the configuration process to be easily scripted or to supply additional information which is not requested during an interactive installation.
ipa-server-install
. The full list of options are in the ipa-server-install
manpage. The ipa-server-install
options are versatile enough to be customized to the specific deployment environment to install and configure different services as needed.
Argument | Description |
---|---|
-a ipa_admin_password | The password for the IdM administrator. This is used for the admin user to authenticate to the Kerberos realm. |
--hostname=hostname | The fully-qualified domain name of the IdM server machine.
Important
This must be a valid DNS name, which means only numbers, alphabetic characters, and hyphens (-) are allowed. Other characters, like underscores, in the hostname will cause DNS failures.
Additionally, the hostname must be all lower-case. No capital letters are allowed.
|
-n domain_name | The name of the LDAP server domain to use for the IdM domain. This is usually based on the IdM server's hostname. |
-p directory_manager_password | The password for the superuser, cn=Directory Manager , for the LDAP service. |
-P kerberos_master_password | The password for the KDC administrator. This is randomly generated if no value is given. |
-r realm_name | The name of the Kerberos realm to create for the IdM domain. |
--subject=subject_DN | Sets the base element for the subject DN of the issued certificates. This defaults to O= realm. |
--forwarder=forwarder | Gives a DNS forwarder to use with the DNS service. To specify more than one forwarder, use this option multiple times. |
--no-forwarders | Uses root servers with the DNS service instead of forwarders. |
--no-reverse | Does not create a reverse DNS zone when the DNS domain is set up. (If a reverse DNS zone is already configured, then that existing reverse DNS zone is used.) If this option is not used, then the default value is true, which assumes that reverse DNS should be configured by the installation script. |
--setup-dns | Tells the installation script to set up a DNS service within the IdM domain. Using an integrated DNS service is optional, so if this option is not passed with the installation script, then no DNS is configured. |
--idmax=number | Sets the upper bound for IDs which can be assigned by the IdM server. The default value is the ID start value plus 199999. |
--idstart=number | Sets the lower bound (starting value) for IDs which can be assigned by the IdM server. The default value is randomly selected. |
--ip-address | Specifies the IP address of the server. When added to ipa-server-install , this option only accepts IP addresses associated with the local interface. |
3.3. Example: Running the Script Interactively and Silently
3.3.1. Basic Interactive Installation
ipa-server-install
script. This launches the script interactively, which prompts for the required information to set up a server, but without more advanced configuration like DNS and CA options.
- Run the
ipa-server-install
script.[root@server ~]# ipa-server-install
- Enter the hostname. This is determined automatically using reverse DNS.
Server host name [ipaserver.example.com]:
- Enter the domain name. This is determined automatically based on the hostname.
Please confirm the domain name [example.com]:
- Enter the new Kerberos realm name. This is usually based on the domain name.
Please provide a realm name [EXAMPLE.COM]:
- Enter the password for the Directory Server superuser,
cn=Directory Manager
. There are password strength requirements for this password, including a minimum password length (eight characters).Directory Manager password: Password (confirm):
- Enter the password for the IdM system user account,
admin
. This user is created on the machine.IPA admin password: Password (confirm):
- The script then reprints the hostname, IP address, and domain name. Confirm that the information is correct.
The IPA Master Server will be configured with Hostname: ipaserver.example.com IP address: 192.168.1.1 Domain name: example.com Realm name: EXAMPLE.COM Continue to configure the system with these values? [no]: yes
- After that, the script configures all of the associated services for IdM, with task counts and progress bars.
Configuring NTP daemon (ntpd) [1/4]: stopping ntpd ... Done configuring NTP daemon (ntpd). Configuring directory server (dirsrv): Estimated time 1 minute [1/38]: creating directory server user .... Configuring certificate server (pki-tomcatd): Estimated time 3 minutes 30 seconds [1/20]: creating certificate server user ... Done configuring certificate server (pki-tomcatd). Configuring Kerberos KDC (krb5kdc): Estimated time 30 seconds [1/10]: adding sasl mappings to the directory ... Done configuring Kerberos KDC (krb5kdc). Configuring kadmin [1/2]: starting kadmin [2/2]: configuring kadmin to start on boot Done configuring kadmin. Configuring ipa_memcached [1/2]: starting ipa_memcached [2/2]: configuring ipa_memcached to start on boot Done configuring ipa_memcached. Configuring ipa-otpd [1/2]: starting ipa-otpd [2/2]: configuring ipa-otpd to start on boot Done configuring ipa-otpd. Configuring the web interface (httpd): Estimated time 1 minute [1/15]: disabling mod_ssl in httpd ... Done configuring the web interface (httpd). Applying LDAP updates Restarting the directory server Restarting the KDC Sample zone file for bind has been created in /tmp/sample.zone.pUfcGp.db Restarting the web server Setup complete
- Restart the
SSH
service to retrieve the Kerberos principal and to refresh the name server switch (NSS) configuration file:[root@server ~]# service sshd restart
- Authenticate to the Kerberos realm using the admin user's credentials to ensure that the user is properly configured and the Kerberos realm is accessible.
[root@server ~]# kinit admin Password for admin@EXAMPLE.COM:
- Test the IdM configuration by running a command like
ipa user-find
. For example:[root@server ~]# ipa user-find admin -------------- 1 user matched -------------- User login: admin Last name: Administrator Home directory: /home/admin Login shell: /bin/bash UID: 939000000 GID: 939000000 Account disabled: False Password: True Kerberos keys available: True ---------------------------- Number of entries returned 1 ----------------------------
3.3.2. Silent (Non-Interactive) Installation
- Passwords for the IdM administrative user and the Directory Server super user (Directory Manager)
- The server hostname
- The Kerberos realm name
- The DNS domain name
ipa-server-install
, along with the -U
to force it to run without requiring user interaction.
Example 3.1. Basic Installation without Interaction
[root@server ~]# ipa-server-install -a secret12 --hostname=ipaserver.example.com -r EXAMPLE.COM -p secret12 -n example.com -U
To accept the default shown in brackets, press the Enter key. The IPA Master Server will be configured with Hostname: ipaserver.example.com IP address: 192.168.1.1 Domain name: example.com
3.4. Examples: Installing with Different CA Configurations
- The Dogtag Certificate System can sign its own certificate. This means that the Dogtag Certificate System instance is a root CA. There are no higher CAs, and the root CA cna set its own certificate policies.This is the default configuration.
- The Dogtag Certificate System CA can be signed by an externally-hosted CA (such as Verisign). In that case, the external CA is the root CA, and the configured Dogtag Certificate System CA is subordinate to that root. This means that the certificates issued within the IdM domain are potentially subject to restrictions set by the root CA for attributes like the validity period.Referencing an external CA still uses a Dogtag Certificate System instance to issue all of the IdM domain certficates; the only difference is that the initial domain CA certificate is issued by a different CA.
certmonger
) to manage IdM domain certificates.
Important
3.4.1. Installing with an Internal Root CA
ipa-server-install
command is run.
[root@server ~]# ipa-server-install ... &< ... The IPA Master Server will be configured with: Hostname: server.example.com IP address: 10.1.1.1 Domain name: example.com Realm name: EXAMPLE.COM Continue to configure the system with these values? [no]: yes The following operations may take some minutes to complete. Please wait until the prompt is returned. ... &< ... Configuring directory server for the CA (pkids): Estimated time 30 seconds [1/3]: creating directory server user [2/3]: creating directory server instance [3/3]: restarting directory server Done configuring directory server for the CA (pkids). Configuring certificate server (pki-cad): Estimated time 3 minutes 30 seconds [1/21]: creating certificate server user ... Done configuring certificate server (pki-cad). ... &< ...
3.4.2. Installing Using an External CA
Important
Basic Constraint
option be set to CA=TRUE
or that the Key Usage Extension be set on the signing certificate to allow it to sign certificates.
Important
Example 3.2. Using an External CA
- Run the
ipa-server-install
script, using the--external-ca
option.[root@server ~]# ipa-server-install -a secret12 -r EXAMPLE.COM -P password -p secret12 -n ipaserver.example.com --external-ca
- The script sets up the NTP and Directory Server services as normal.
- The script completes the CA setup and returns information about where the certificate signing request (CSR) is located,
/root/ipa.csr
. This request must be submitted to the external CA.Configuring certificate server: Estimated time 6 minutes [1/4]: creating certificate server user [2/4]: creating pki-ca instance [3/4]: restarting certificate server [4/4]: configuring certificate server instance The next step is to get /root/ipa.csr signed by your CA and re-run ipa-server-install.
- Submit the request to the CA. The process differs for every service.It may be necessary to request the appropriate extensions for the certificate. The CA signing certificate generated for the Identity Management server must be a valid CA certificate. This requires either that the Basic Constraint be set to CA=true or that the Key Usage Extension be set on the signing certificate to allow it to sign certificates.
- Retrieve the issued certificate and the CA certificate chain for the issuing CA. Again, the process differs for every certificate service, but there is usually a download link on a web page or in the notification email that allows administrators to download all the required certificates. Be sure to get the full certificate chain for the CA, not just the CA certificate.
- Rerun
ipa-server-install
, specifying the locations and names of the certificate and CA chain files. For example:[root@server ~]# ipa-server-install --external_cert_file=/tmp/servercert20110601.p12 --external_ca_file=/tmp/cacert.p12
- Complete the setup process and verify that everything is working as expected, as in Section 3.3.1, “Basic Interactive Installation”.
3.4.3. Installing without a CA
- An LDAP server certificate
- An Apache server certificate
- An LDAP server certificate
certmonger
is not used to track certificates, so there is no expiration warning.- There is no way to renew certificates through Identity Management.
- The certificate management tools (
ipa cert-*
) cannot be used to view or manage certificates. - All host certificates and any service certificates must be requested, generated, and uploaded manually. This also affects how host management tools like
ipa host-add
function. - If a certificate is removed from an entry, it is not automatically revoked.
Important
Example 3.3. Installing Identity Management Without a CA
- LDAP server certificate
- --dirsrv_pkcs12, with the PKCS#12 certificate file for the LDAP server certificate
- --dirsrv_pin, with the password to access the PKCS#12 file
- Apache server certificate
- --http_pkcs12, with the PKCS#12 certificate file for the Apache server certificate
- --http_pin, with the password to access the PKCS#12 file
- Root CA certificate (to allow the Apache and LDAP server certificates to be trusted across the domain)
[root@server ~]# ipa-server-install --http_pkcs12 /tmp-http-server.p12 --http_pin secret1 --dirsrv_pkcs12 /tmp/ldap-server.p12 --dirsrv_pin secret2 ...
3.5. Example: Configuring DNS Services within the IdM Domain
--setup-dns
option.
Warning
3.5.1. DNS Notes
- Wildcards cannot be used when configuring DNS names. Only explicit DNS domain names are supported.
- The
rndc
service is not configured by the--setup-dns
option. This service must be configured manually after the IdM server is configured.
3.5.2. Installing with an Integrated DNS
Example 3.4. Interactive DNS Setup
- Run the
ipa-server-install
script, using the--setup-dns
option.[root@server ~]# ipa-server-install -a secret12 -r EXAMPLE.COM -P password -p secret12 -n ipaserver.example.com --setup-dns
- The script configures the hostname and domain name as normal.
- The script then prompts for DNS forwarders. If forwarders will be used, enter yes, and then supply the list of DNS servers. If IdM will manage its own DNS service, then enter no.
Do you want to configure DNS forwarders? [yes]: no No DNS forwarders configured
- The script sets up the NTP, Directory Server, Certificate System, Kerberos, and Apache services.
- Before completing the configuration, the script prompts to ask whether it should configure reverse DNS services. If you select yes, then it configures the
named
service.Do you want to configure the reverse zone? [yes]: yes Configuring DNS (named) [1/11]: adding DNS container [2/11]: setting up our zone [3/11]: setting up reverse zone [4/11]: setting up our own record [5/11]: setting up records for other masters [6/11]: setting up CA record [7/11]: setting up kerberos principal [8/11]: setting up named.conf [9/11]: restarting named [10/11]: configuring named to start on boot [11/11]: changing resolv.conf to point to ourselves Done configuring DNS (named). ============================================================================== Setup complete
- The
ipa-dns-install
command (which is run with the install script when the--setup-dns
option is used) does not automatically configure the system'srndc
service. This must be configured manually, after DNS is configured for IdM.- Create the
rndc
configuration file and key.[root@server ~]# /usr/sbin/rndc-confgen -a [root@server ~]# /sbin/restorecon /etc/rndc.key
This may require some user input to create entropy while the key is being created. - Change the owner and permissions of the
rndc
key file.[root@server ~]# chown root:named /etc/rndc.key [root@server ~]# chmod 0640 /etc/rndc.key
- Verify that everything is working as expected, as in Section 3.3.1, “Basic Interactive Installation”.
--forwarder
or --no-forwarders
option and --no-reverse
option.
Example 3.5. Setting up DNS Non-Interactively
--setup-dns
option. To configure additional forwarders, use the --forwarder
option; for multiple forwarders, use multiple invocations of --forwarder
.
[root@server ~]# ipa-server-install ... --setup-dns --forwarder=1.2.3.0 --forwarder=1.2.255.0
--no-forwarders
option to indicate that only root servers will be used.
--no-reverse
option; if a reverse DNS zone is already configured, then using the --no-reverse
option means that existing reverse DNS zone is used.
[root@server ~]# ipa-server-install ... --setup-dns --no-reverse
ipa-dns-install
command (which is run with the install script when the --setup-dns
option is used) does not automatically configure the system's rndc
service. This must be configured manually, after DNS is configured for IdM.
- Create the
rndc
configuration file and key.[root@server ~]# /usr/sbin/rndc-confgen -a [root@server ~]# /sbin/restorecon /etc/rndc.key
This may require some user input to create entropy while the key is being created. - Change the owner and permissions of the
rndc
key file.[root@server ~]# chown root:named /etc/rndc.key [root@server ~]# chmod 0640 /etc/rndc.key
Chapter 4. Setting up IdM Replicas
4.1. Planning the Server/Replica Topologies
- Servers, which manage all of the services used by domain members
- Replicas, which are essentially copies of servers (and, once copied, are identical to servers)
- Clients, which belong to the Kerberos domains, receive certificates and tickets issued by the servers, and use other centralized services for authentication and authorization
ipa-replica-manage
command.
Figure 4.1. Server and Replica Agreements
- No more than four replication agreements can be configured on a single server/replica.
- No more than 20 servers and replicas should be involved in a single Identity Management domain.
- Every server/replica should have a minimum of two replication agreements to ensure that there are no orphan servers or replicas cut out of the IdM domain if another server fails.
Figure 4.2. Example Topology
- Have at least one IdM server in each main office, data center, or locality. Preferably, have two IdM servers.
- Do not have more than four servers per data center.
- Rather than using a server or replica, small offices can use SSSD to cache credentials and use an off-site IdM server as its data backend.
4.2. Prerequisites for Installing a Replica Server
- Make sure that the machine meets all of the prerequisites listed in Chapter 2, Prerequisites for Installation.
- The replica and the master server must be running the same version of IdM.The replica essentially is a copy of a server, based off the existing server configuration. Therefore, the server and the replica (its copy) must be running the same version of Identity Management so that the configuration can be properly copied from the server to the replica.If the master server is running on Red Hat Enterprise Linux 6, IdM version 3.0, then the replica must also run on Red Hat Enterprise Linux 6 and use the IdM 3.0 packages.
Important
Creating a replica of a different version than the master is not supported. Attempting to create a replica using a different version fails when attempting to configure the 389 Directory Server instance. - Apart from the ports listed in Table 2.1, “IdM Ports”, installing a replica also requires
port 22
to be free during the replica setup process. This port is required in order to use SSH to connect to the master server.Port 7389
must be free if there is an existing Dogtag Certificate System or Red Hat Certificate System instance on the replica machine during and after the replica configuration. This port is used by the master IdM server to communicate with the replica.Note
Theipa-replica-install
script includes theipa-replica-conncheck
utility that verifies the status of the required ports. You can also runipa-replica-conncheck
separately for troubleshooting purposes. For information on how to use the utility, see the ipa-replica-conncheck(1) man page. - The replica must use the same CA configuration as the server and must have the same root CA. For example, if the server is its own root CA (using Dogtag Certificate System), then that must be the root CA for the replica. If the server used an external CA to issue its certificates, than the replica must use that same external CA.
4.3. Installing the Replica Packages
ipa-server
. If the replica will also host DNS services, then include the bind
and bind-dyndb-ldap
packages.
[root@server ~]# yum install ipa-server bind bind-dyndb-ldap
Important
ipa-server-install
script.
4.4. Creating the Replica
- On the master server, create a replica information file. This contains realm and configuration information taken from the master server which will be used to configure the replica server.Run the
ipa-replica-prepare
utility on the master IdM server. The utility requires the fully-qualified domain name of the replica machine.Using the--ip-address
option automatically creates DNS entries for the replica, including the A and PTR records for the replica to the DNS.Important
Only pass the--ip-address
option if the IdM server was configured with integrated DNS. Otherwise, there is no DNS record to update, and the attempt to create the replica fails when the DNS record operation fails.Note
Theipa-replica-prepare
script does not validate the IP address or verify if the IP address of the replica is reachable by other servers.[root@server ~]# ipa-replica-prepare ipareplica.example.com --ip-address 192.168.1.2 Directory Manager (existing master) password: Preparing replica for ipareplica.example.com from ipaserver.example.com Creating SSL certificate for the Directory Server Creating SSL certificate for the dogtag Directory Server Saving dogtag Directory Server port Creating SSL certificate for the Web Server Exporting RA certificate Copying additional files Finalizing configuration Packaging replica information into /var/lib/ipa/replica-info-ipareplica.example.com.gpg Adding DNS records for ipareplica.example.com Using reverse zone 1.168.192.in-addr.arpa. The ipa-replica-prepare command was successful
This must be a valid DNS name, which means only numbers, alphabetic characters, and hyphens (-) are allowed. Other characters, like underscores, in the hostname will cause DNS failures. Additionally, the hostname must be all lower-case. No capital letters are allowed.Each replica information file is created in the/var/lib/ipa/
directory as a GPG-encrypted file. Each file is named specifically for the replica server for which it is intended, such asreplica-info-ipareplica.example.com.gpg
.Note
A replica information file cannot be used to create multiple replicas. It can only be used for the specific replica and machine for which it was created.Warning
Replica information files contain sensitive information. Take appropriate steps to ensure that they are properly protected.For more options withipa-replica-prepare
, see the ipa-replica-prepare(1) man page. - Copy the replica information file to the replica server:
[root@server ~]# scp /var/lib/ipa/replica-info-ipareplica.example.com.gpg root@ipaserver:/var/lib/ipa/
- On the replica server, run the replica installation script, referencing the replication information file. There are other options for setting up DNS, much like the server installation script. Additionally, there is an option to configure a CA for the replica; while CA's are installed by default for servers, they are optional for replicas.Some information about DNS forwarders is required. A list can be given of configured DNS forwarders using a
--forwarder
option for each one, or forwarder configuration can be skipped by specifying the--no-forwarders
option.For example:[root@ipareplica ~]# ipa-replica-install --setup-ca --setup-dns --no-forwarders /var/lib/ipa/replica-info-ipareplica.example.com.gpg Directory Manager (existing master) password: Warning: Hostname (ipareplica.example.com) not found in DNS Run connection check to master Check connection from replica to remote master 'ipareplica. example.com': Directory Service: Unsecure port (389): OK Directory Service: Secure port (636): OK Kerberos KDC: TCP (88): OK Kerberos Kpasswd: TCP (464): OK HTTP Server: Unsecure port (80): OK HTTP Server: Secure port (443): OK The following list of ports use UDP protocol and would need to be checked manually: Kerberos KDC: UDP (88): SKIPPED Kerberos Kpasswd: UDP (464): SKIPPED Connection from replica to master is OK. Start listening on required ports for remote master check Get credentials to log in to remote master admin@EXAMPLE.COM password: Execute check on remote master admin@example.com's password: Check connection from master to remote replica 'ipareplica. example.com': Directory Service: Unsecure port (389): OK Directory Service: Secure port (636): OK Kerberos KDC: TCP (88): OK Kerberos KDC: UDP (88): OK Kerberos Kpasswd: TCP (464): OK Kerberos Kpasswd: UDP (464): OK HTTP Server: Unsecure port (80): OK HTTP Server: Secure port (443): OK Connection from master to replica is OK. Connection check OK
The replica installation script runs a test to ensure that the replica file being installed matches the current hostname. If they do not match, the script returns a warning message and asks for confirmation. This could occur on a multi-homed machine, for example, where mismatched hostnames may not be an issue.Additional options for the replica installation script are listed in the ipa-replica-install(1) man page.Note
One of the optionsipa-replica-install
accepts is the--ip-address
option. When added toipa-replica-install
, this option only accepts IP addresses associated with the local interface. - Enter the Directory Manager password when prompted. The script then configures a Directory Server instance based on information in the replica information file and initiates a replication process to copy over data from the master server to the replica, a process called initialization.
- Verify that the proper DNS entries were created so that IdM clients can discover the new server. DNS entries are required for required domain services:
- _ldap._tcp
- _kerberos._tcp
- _kerberos._udp
- _kerberos-master._tcp
- _kerberos-master._udp
- _ntp._udp
If the initial IdM server was created with DNS enabled, then the replica is created with the proper DNS entries. For example:[root@ipareplica ~]# DOMAIN=example.com [root@ipareplica ~]# NAMESERVER=ipareplica [root@ipareplica ~]# for i in _ldap._tcp _kerberos._tcp _kerberos._udp _kerberos-master._tcp _kerberos-master._udp _ntp._udp; do echo ""; dig @${NAMESERVER} ${i}.${DOMAIN} srv +nocmd +noquestion +nocomments +nostats +noaa +noadditional +noauthority; done | egrep -v "^;" | egrep _ _ldap._tcp.example.com. 86400 IN SRV 0 100 389 ipaserver1.example.com. _ldap._tcp.example.com. 86400 IN SRV 0 100 389 ipaserver2.example.com. _kerberos._tcp.example.com. 86400 IN SRV 0 100 88 ipaserver1.example.com. ...8<...
If the initial IdM server was created without DNS enabled, then each DNS entry, including both TCP and UDP entries for some services, should be added manually. For example:[root@ipareplica ~]# kinit admin [root@ipareplica ~]# ipa dnsrecord-add example.com _ldap._tcp --srv-rec="0 100 389 ipareplica.example.com."
- Optional. Set up DNS services for the replica. These are not configured by the setup script, even if the master server uses DNS.Use the
ipa-dns-install
command to install the DNS manually, then use theipa dnsrecord-add
command to add the required DNS records. For example:[root@ipareplica ~]# ipa-dns-install [root@ipareplica ~]# ipa dnsrecord-add example.com @ --ns-rec ipareplica.example.com.
Important
Use the fully-qualified domain name of the replica, including the final period (.), otherwise BIND will treat the hostname as relative to the domain.
4.5. Alternate Options for Creating a Replica
ipa-replica-prepare
command or in the ipa-replica-install
command.
4.5.1. Different DNS Settings
ipa-replica-prepare
command can be used to configure DNS settings specific to the replica, meaning its IP address and reverse zone. For example:
[root@server ~]# ipa-replica-prepare ipareplica.example.com --ip-address=192.68.0.0 --no-reverse
--setup-dns
option, and then settings for forward and reverse zones. For example, to configure DNS services for the replica with no forwarders and using an existing reverse zone:
[root@server ~]# ipa-replica-install ipareplica.example.com --setup-dns --no-forwarders --no-reverse --no-host-dns ...
ipa-replica-prepare
and ipa-replica-install
manpages.
4.5.2. Different CA Settings
--setup-ca
option. The rest of the configuration is taken from the server's configuration.
[root@ipareplica ~]# ipa-replica-install ipareplica.example.com --setup-ca ...
[root@ipareplica ~]# ipa-replica-install ipareplica.example.com --dirsrv_pkcs12=/tmp/dirsrv-cert.p12 --dirsrv_pin=secret1 --http_pkcs12=/tmp/http-cert.p12 --http_pin=secret2 ...
4.5.3. Different Services
[root@server ~]# ipa-replica-install ... --no-ntp --no-ssh --no-sshd ...
Chapter 5. Setting up Systems as IdM Clients
Note
Note
5.1. What Happens in Client Setup
- Retrieve the CA certificate for the IdM CA.
- Create a separate Kerberos configuration to test the provided credentials.This enables a Kerberos connection to the IdM XML-RPC server, necessary to join the IdM client to the IdM domain. This Kerberos configuration is ultimately discarded.Setting up the Kerberos configuration includes specifying the realm and domain details, and default ticket attributes. Forwardable tickets are configured by default, which facilitates connection to the administration interface from any operating system, and also provides for auditing of administration operations. For example, this is the Kerberos configuration for Red Hat Enterprise Linux systems:
[libdefaults] default_realm = EXAMPLE.COM dns_lookup_realm = false dns_lookup_kdc = false rdns = false forwardable = yes ticket_lifetime = 24h [realms] EXAMPLE.COM = { kdc = server.example.com:88 admin_server = server.example.com:749 } [domain_realm] .example.com = EXAMPLE.COM example.com = EXAMPLE.COM
- Run the
ipa-join
command to perform the actual join. - Obtain a service principal for the host service and installs it into
/etc/krb5.keytab
. For example,host/ipa.example.com@EXAMPLE.COM
. - Enable certmonger, retrieve an SSL server certificate, and install the certificate in
/etc/pki/nssdb
. - Disable the nscd daemon.
- Configure SSSD or LDAP/KRB5, including NSS and PAM configuration files.
- Configure an OpenSSH server and client, as well as enabling the host to create DNS SSHFP records.
- Configure NTP.
5.2. System Ports
5.3. Configuring a Linux System as an IdM Client
- There must be a way to connect the client machine to the Kerberos domain, either by having an available Kerberos identity (such as the admin user) or by manually adding the client machine to the KDC on the server with a one-time password before beginning the enrollment process for the client machine.
- If there is an Active Directory server on the same network that serves DNS records, the Active Directory DNS records could prevent the client from automatically detecting the IdM server address. The
ipa-client-install
script retrieves the Active Directory DNS records instead of any records that were added for IdM.In this case, it is necessary to pass the IdM server address directly to theipa-client-install
script.
5.3.1. Installing the Client (Full Example)
- Install the client packages. These packages provide a simple way to configure the system as a client; they also install and configure SSSD.For a regular user system, this requires only the
ipa-client
package:[root@client ~]# yum install ipa-client
An administrator machine requires theipa-admintools
package, as well:[root@client ~]# yum install ipa-client ipa-admintools
- If the IdM server is configured as the DNS server and is in the same domain as the client, add the server's IP address as the first entry in the list of name servers in the client's
/etc/resolv.conf
file.Note
If every machine in the domain will be an IdM client, then add the IdM server address to the DHCP configuration. - Run the client setup command.
[root@client ~]# ipa-client-install --enable-dns-updates
The--enable-dns-updates
option updates DNS with the client machine's IP address. This option should only be used if the IdM server was installed with integrated DNS or if the DNS server on the network accepts DNS entry updates with the GSS-TSIG protocol.Options foripa-client-install
are listed in theipa-client-install
manpage. - If prompted, enter the domain name for the IdM DNS domain.
DNS discovery failed to determine your DNS domain Please provide the domain name of your IPA server (ex: example.com): example.com
- If prompted, enter the fully-qualified domain name of the IdM server. Alternatively, use the
--server
option with the client installation script to supply the fully-qualified domain name of the IdM server.DNS discovery failed to find the IPA Server Please provide your IPA server name (ex: ipa.example.com): server.example.com
Important
This must be a valid DNS name, which means only numbers, alphabetic characters, and hyphens (-) are allowed. Other characters, like underscores, in the hostname will cause DNS failures. - The client script then prompts for a Kerberos identity to use to contact and then join the Kerberos realm. When these credentials are supplied, then the client is able to join the IdM Kerberos domain and then complete the configuration:
Continue to configure the system with these values? [no]: y User authorized to enroll computers: admin Synchronizing time with KDC... Password for admin@EXAMPLE.COM: Successfully retrieved CA cert Subject: CN=Certificate Authority,O=EXAMPLE.COM Issuer: CN=Certificate Authority,O=EXAMPLE.COM Valid From: Tue Aug 13 09:29:07 2013 UTC Valid Until: Sat Aug 13 09:29:07 2033 UTC Enrolled in IPA realm EXAMPLE.COM Created /etc/ipa/default.conf New SSSD config will be created Configured /etc/sssd/sssd.conf Configured /etc/krb5.conf for IPA realm EXAMPLE.COM Failed to update DNS records. Adding SSH public key from /etc/ssh/ssh_host_rsa_key.pub Adding SSH public key from /etc/ssh/ssh_host_dsa_key.pub Could not update DNS SSHFP records. SSSD enabled Configured /etc/openldap/ldap.conf NTP enabled Configured /etc/ssh/ssh_config Configured /etc/ssh/sshd_config Client configuration complete.
- Test that the client can connect successfully to the IdM domain and can perform basic tasks. For example, check that the IdM tools can be used to get user and group information:
[jsmith@client ~]$ id [jsmith@client ~]$ getent passwd admin [jsmith@client ~]$ getent group admins
- If an NFS server is already configured, then set NFS on the client system to work with Kerberos.An NFS server must already be configured within the domain. This is covered in Section 18.2, “Configuring Automount”.
Note
To help troubleshoot potential NFS setup errors, enable debug information in the/etc/sysconfig/nfs
file.RPCGSSDARGS="-vvv" RPCSVCGSSDARGS="-vvv"
- On an IdM server, add an NFS service principal for the NFS client.
[root@client ~]# kinit admin [root@client ~]# ipa service-add nfs/ipaclient.example.com@EXAMPLE
Note
This must be run from a machine with the ipa-admintools package installed so that theipa
command is available. - On the IdM server, obtain a keytab for the NFS service principal.
[root@client ~]# ipa-getkeytab -s server.example.com -p nfs/ipaclient.example.com@EXAMPLE -k /tmp/krb5.keytab
- Copy the keytab from the IdM server to the IdM client. For example:
[root@client ~]# scp /tmp/krb5.keytab root@client.example.com:/etc/krb5.keytab
- Configure the
/etc/exports
file on the NFS server./ipashare gss/krb5p(rw,no_root_squash,subtree_check,fsid=0)
- Create the mount point.
[root@client ~]# mkdir /mnt/ipashare
- On the client, mount the NFS share. Use the same
-o sec
setting as is used in the/etc/exports
file for the NFS server.[root@client ~]# mount -v -t nfs4 -o sec=krb5p nfs.example.com:/ /mnt/ipashare
5.3.2. Examples of Other Client Installation Options
ipa-client-install
command which can be used to configure the client system in different ways, depending on the infrastructure requirements.
Example 5.1. Enabling DNS Updates
--enable-dns-updates
option sets the System Security Services Daemon to update the DNS entries whenever the IP address for a client changes.
[root@client ~]# ipa-client-install --enable-dns-updates
Example 5.2. Specifying Domain Information
--domain
for the DNS domain name (which is only used if the IdM server is configured to host DNS services)--server
for the IdM server to register with (which can be any server or replica in the topology)This must be a valid DNS name, which means only numbers, alphabetic characters, and hyphens (-) are allowed. Other characters, like underscores, in the hostname will cause DNS failures.--realm
for the Kerbero realm name and, optionally,-p
for a Kerberos principal name
[root@client ~]# ipa-client-install --domain EXAMPLE.COM --server server.example.com --realm EXAMPLE -p host/server.example.com
Example 5.3. Setting a Specific IdM Server
--fixed-primary
option.
[root@client ~]# ipa-client-install --fixed-primary server.example.com
Example 5.4. Disabling System Authentication Tools
authconfig
tool to set and update authentication clients and settings for a local system. Identity Management uses the System Security Services Daemon (SSSD) to store IdM server configuration and to retrieve policy information, users, passwords, and groups configured within the IdM domain.
authconfig
or SSSD.
--noac
option prevents any changes through authconfig
. The --no-sssd
option prevents IdM from using SSSD.
[root@client ~]# ipa-client-install --noac --no-sssd
--preserve-sssd
. While this allows the client to change the SSSD configuration file to configure the IdM domain, it saves the old SSSD configuration.
Example 5.5. Disabling Password Caching
--no-krb5-offline-passwords
option can be used to prevent passwords from being cached in SSSD.
[root@client ~]# ipa-client-install --no-krb5-offline-passwords
5.4. Manually Configuring a Linux Client
ipa-client-install
command automatically configures services like Kerberos, SSSD, PAM, and NSS. However, if the ipa-client-install
command cannot be used on a system for some reason, then the IdM client entries and the services can be configured manually.
5.4.1. Setting up an IdM Client (Full Procedure)
- Install SSSD, if it is not already installed.
- Optional. Install the IdM tools so that administrative tasks can be performed from the host.
[root@client ~]# yum install ipa-admintools
- On an IdM server. Create a host entry for the client.
[jsmith@client ~]$ kinit admin [jsmith@client ~]$ ipa host-add --force --ip-address=192.168.166.31 ipaclient.example.com
Creating hosts manually is covered in Section 5.4.2, “Other Examples of Adding a Host Entry”. - On an IdM server. Create keytabs for the client.
- Log in as IdM administrator.
[jsmith@client ~]$ kinit admin
- Set the client host to be managed by the server.
[jsmith@client ~]$ ipa host-add-managedby --hosts=server.example.com ipaclient.example.com
- Generate the keytab for the client.
[jsmith@client ~]$ ipa-getkeytab -s server.example.com -p host/ipaclient.example.com -k /tmp/ipaclient.keytab
- Copy the keytab to the client machine and rename it
/etc/krb5.keytab
.Note
If there is an existing/etc/krb5.keytab
that should be preserved, the two files can be combined usingktutil
. - Set the correct user permissions for the
/etc/krb5.keytab
file.[root@client ~]# chown root:root /etc/krb5.keytab [root@client ~]# chmod 0600 /etc/krb5.keytab
- Set the SELinux contexts for the
/etc/krb5.keytab
file.[root@client ~]# chcon system_u:object_r:krb5_keytab_t:s0 /etc/krb5.keytab
- Configure SSSD by editing the
/etc/sssd/sssd.conf
file to point to the IdM domain.[root@client ~]# touch /etc/sssd/sssd.conf [root@client ~]# vim /etc/sssd/sssd.conf [sssd] config_file_version = 2 services = nss, pam domains = example.com [nss] [pam] [domain/example.com] cache_credentials = True krb5_store_password_if_offline = True ipa_domain = example.com id_provider = ipa auth_provider = ipa access_provider = ipa ipa_hostname = ipaclient.example.com chpass_provider = ipa ipa_server = server.example.com ldap_tls_cacert = /etc/ipa/ca.crt
- Configure NSS to use SSSD for passwords, groups, users, and netgroups.
[root@client ~]# vim /etc/nsswitch.conf ... passwd: files sss shadow: files sss group: files sss ... netgroup: files sss ...
- Configure the
/etc/krb5.conf
file to point to the IdM KDC.[logging] default = FILE:/var/log/krb5libs.log kdc = FILE:/var/log/krb5kdc.log admin_server = FILE:/var/log/kadmind.log [libdefaults] default_realm = EXAMPLE.COM dns_lookup_realm = false dns_lookup_kdc = false rdns = false ticket_lifetime = 24h forwardable = yes allow_weak_crypto = true [realms] EXAMPLE.COM = { kdc = server.example.com:88 admin_server = server.example.com:749 default_domain = example.com } [domain_realm] .example.com = EXAMPLE.COM example.com = EXAMPLE.COM
- Update the
/etc/pam.d
configuration to use thepam_sss.so
modules.- For
/etc/pam.d/fingerprint-auth
:... account [default=bad success=ok user_unknown=ignore] pam_sss.so ... session optional pam_sss.so
- For
/etc/pam.d/system-auth
:... auth sufficient pam_sss.so use_first_pass ... account [default=bad success=ok user_unknown=ignore] pam_sss.so ... password sufficient pam_sss.so use_authtok ... session optional pam_sss.so
- For
/etc/pam.d/password-auth
:... auth sufficient pam_sss.so use_first_pass ... account [default=bad success=ok user_unknown=ignore] pam_sss.so ... password sufficient pam_sss.so use_authtok ... session optional pam_sss.so
- Enrollment_with_Separation_of_DutiesFor
/etc/pam.d/smartcard-auth
:... account [default=bad success=ok user_unknown=ignore] pam_sss.so ... session optional pam_sss.so
- Install the IdM server's CA certificate.
- Obtain the certificate from the server.
[root@ipaclient ~]# wget -O /etc/ipa/ca.crt http://ipa.example.com/ipa/config/ca.crt
- Install the certificate in the system's NSS database.
[root@ipaclient ~]# certutil -A -d /etc/pki/nssdb -n "IPA CA" -t CT,C,C -a -i /etc/ipa/ca.crt
- Set up a host certificate for the host in IdM.
- Make sure
certmonger
is running.[root@ipaclient ~]# service certmonger start
Note
Configurechkconfig
so that thecertmonger
service starts by default.[root@ipaclient ~]# chkconfig certmonger on
- Use the
ipa-getcert
command, which creates and manages the certificate throughcertmonger
. The options are described more in Section B.1, “Requesting a Certificate with certmonger”.[root@ipaclient ~]# ipa-getcert request -d /etc/pki/nssdb -n Server-Cert -K HOST/ipaclient.example.com -N 'CN=ipaclient.example.com,O=EXAMPLE.COM'
If administrative tools were not installed on the client, then the certificate can be generated on an IdM server, copied over to the host, and installed usingcertutil
. - Set up NFS to work with Kerberos.
Note
To help troubleshoot potential NFS setup errors, enable debug information in the/etc/sysconfig/nfs
file.RPCGSSDARGS="-vvv" RPCSVCGSSDARGS="-vvv"
- On an IdM server, add an NFS service principal for the NFS client.
[root@ipaclient ~]# ipa service-add nfs/ipaclient.example.com@EXAMPLE
Note
This must be run from a machine with the ipa-admintools package installed so that theipa
command is available. - On the IdM server, obtain a keytab for the NFS service principal.
[root@ipaclient ~]# ipa-getkeytab -s server.example.com -p nfs/ipaclient.example.com@EXAMPLE -k /tmp/krb5.keytab
Note
Some versions of the Linux NFS implementation have limited encryption type support. If the NFS server is hosted on a version older than Red Hat Enterprise Linux 6, use the-e des-cbc-crc
option to theipa-getkeytab
command for any nfs/<FQDN> service keytabs to set up, both on the server and on all clients. This instructs the KDC to generate only DES keys.When using DES keys, all clients and servers that rely on this encryption type need to have theallow_weak_crypto
option enabled in the[libdefaults]
section of the/etc/krb5.conf
file. Without these configuration changes, NFS clients and servers are unable to authenticate to each other, and attempts to mount NFS filesystems may fail. The client'srpc.gssd
and the server'srpc.svcgssd
daemons may log errors indicating that DES encryption types are not permitted. - Copy the keytab from the IdM server to the NFS server. For example, if the IdM and NFS servers are on different machines:
[root@ipaclient ~]# scp /tmp/krb5.keytab root@nfs.example.com:/etc/krb5.keytab
- Copy the keytab from the IdM server to the IdM client. For example:
[root@ipaclient ~]# scp /tmp/krb5.keytab root@client.example.com:/etc/krb5.keytab
- Configure the
/etc/exports
file on the NFS server./ipashare gss/krb5p(rw,no_root_squash,subtree_check,fsid=0)
- On the client, mount the NFS share.
- Always specify the share as nfs_server:/ /mountpoint.
- Use the same
-o sec
setting as is used in the/etc/exports
file for the NFS server.
[root@client ~]# mount -v -t nfs4 -o sec=krb5p nfs.example.com:/ /mnt/ipashare
5.4.2. Other Examples of Adding a Host Entry
5.4.2.1. Adding Host Entries from the Web UI
- Open the Identity tab, and select the Hosts subtab.
- Click the Add link at the top of the hosts list.
- Fill in the machine name and select the domain from the configured zones in the drop-down list. If the host has already been assigned a static IP address, then include that with the host entry so that the DNS entry is fully created.DNS zones can be created in IdM, which is described in Section 17.6.1, “Adding Forward DNS Zones”. If the IdM server does not manage the DNS server, the zone can be entered manually in the menu area, like a regular text field.
Note
Select the Force checkbox to add the host DNS record, even if the hostname cannot be resolved.This is useful for hosts which use DHCP and do not have a static IP address. This essentially creates a placeholder entry in the IdM DNS service. When the DNS service dynamically updates its records, the host's current IP address is detected and its DNS record is updated. - Click the Add and Edit button to go directly to the expanded entry page and fill in more attribute information. Information about the host hardware and physical location can be included with the host entry.
5.4.2.2. Adding Host Entries from the Command Line
host-add
command. This commands adds the host entry to the IdM Directory Server. The full list of options with host-add
are listed in the ipa host
manpage. At its most basic, an add operation only requires the client hostname to add the client to the Kerberos realm and to create an entry in the IdM LDAP server:
$ ipa host-add client1.example.com
--ip-address
and --force
options.
Example 5.6. Creating Host Entries with Static IP Addresses
$ ipa host-add --force --ip-address=192.168.166.31 client1.example.com
--force
. This essentially creates a placeholder entry in the IdM DNS service. When the DNS service dynamically updates its records, the host's current IP address is detected and its DNS record is updated.
Example 5.7. Creating Host Entries with DHCP
$ ipa host-add --force client1.example.com
host-del
command. If the IdM domain uses DNS, then the --updatedns
option also removes the associated records of any kind for the host from the DNS.
$ ipa host-del --updatedns client1.example.com
5.5. Setting up a Linux Client Through Kickstart
- Create the host entry on the IdM server and set a temporary Kerberos password for the entry.When the
ipa-client-install
script is run normally (interactively), it prompts for authentication credentials to access the IdM domain. However, when the script is run automatically, the system has to have some way to access the IdM domain without using an existing IdM user; this is done by setting the host principal in the script and using a Kerberos password (configured for the host account) to access the IdM domain.For example:[jsmith@server ~]$ ipa host-add kickstart-server.example.com --password=secret
The password expires after the first authentication attempt. After enrollment completes, the host is authenticated using its keytab. - Include the ipa-client package with the other install packages.
%packages @ X Window System @ Desktop @ Sound and Video ipa-client ...
- Create a post-install instruction that ensures SSH keys are generated before enrollment, runs the
ipa-client-install
script, passes all the required information to access and configure the IdM domain services, and specifies the pre-set password. Use the--unattended
option to instruct the script to run non-interactively.%post --log=/root/ks-post.log # Generate SSH keys to ensure that ipa-client-install uploads them to the IdM server /usr/bin/ssh-keygen -q -t rsa -f /etc/ssh/ssh_host_rsa_key -C '' -N '' chmod 600 /etc/ssh/ssh_host_rsa_key chmod 644 /etc/ssh/ssh_host_rsa_key.pub /sbin/restorecon /etc/ssh/ssh_host_rsa_key.pub /usr/bin/ssh-keygen -q -t rsa1 -f /etc/ssh/ssh_host_key -C '' -N '' chmod 600 /etc/ssh/ssh_host_key chmod 644 /etc/ssh/ssh_host_key.pub /sbin/restorecon /etc/ssh/ssh_host_key.pub /usr/bin/ssh-keygen -q -t dsa -f /etc/ssh/ssh_host_dsa_key -C '' -N '' chmod 600 /etc/ssh/ssh_host_dsa_key chmod 644 /etc/ssh/ssh_host_dsa_key.pub /sbin/restorecon /etc/ssh/ssh_host_dsa_key.pub # Get the hostname to set as the host principal /bin/hostname > /tmp/hostname.txt # Run the client install script /usr/sbin/ipa-client-install --domain=EXAMPLEDOMAIN --enable-dns-updates --mkhomedir -w secret --realm=EXAMPLEREALM --server=server.example.com --unattended
Note
Red Hat recommends not to start thesshd
service prior to the kickstart enrollment. While startingsshd
before enrolling the client generates the SSH keys automatically, using the above script is the preferred solution. - Run the kickstart script.
5.6. Performing a Two-Administrator Enrollment
ipa-client-install
command. It is also possible to perform those steps separately; this allows for administrators to prepare machines and the IdM server configuration in advance of actually configuring the clients. This allows more flexible setup scenarios, including bulk deployments.
Note
ipa-client-install
command and allowing it to create the host. However, that administrator may have the right to run the command after a host entry exists. In that case, one administrator can create the host entry manually, then the second administrator can complete the enrollment by running the ipa-client-install
command.
- An administrator creates the host entry, as described in Section 5.4.2, “Other Examples of Adding a Host Entry”.
- The second administrator installs the IdM client packages on the machine, as in Section 5.3, “Configuring a Linux System as an IdM Client”.
- When the second administrator runs the setup script, he must pass his Kerberos password and username (principal) with the
ipa-client-install
command. For example:$ ipa-client-install -w secret -p admin2
- The keytab is generated on the server and provisioned to the client machine, so that the client machine is not able to connect to the IdM domain. The keytab is saved with
root:root
ownership and 0600 permissions.
5.7. Manually Unconfiguring Client Machines
--updatedns
option, as when installing a client, to update the domain DNS configuration automatically.
[root@server ~]# ipa-client-install --uninstall --updatedns
Warning
- On the client, remove the old hostname from the main keytab. This can be done by removing every principal in the realm or by removing specific principals. For example, to remove all principals:
[jsmith@client ~]$ ipa-rmkeytab -k /etc/krb5.keytab -r EXAMPLE.COM
To remove specific principals:[jsmith@client ~]$ ipa-rmkeytab -k /etc/krb5.keytab -p host/server.example.com@EXAMPLE.COM
- On the client system, disable tracking in
certmonger
for every certificate. Each certificate must be removed from tracking individually.First, list every certificate being tracked, and extract the database and nickname for each certificate. The number of certificates depends on the configured services for the host.[jsmith@client ~]$ ipa-getcert list
Then, disable tracking for each. For example:[jsmith@client ~]$ ipa-getcert stop-tracking -n "Server-Cert" -d /etc/httpd/alias
- On the IdM server, remove the old host from the IdM DNS domain. While this is optional, it cleans up the old IdM entries associated with the system and allows it to be re-enrolled cleanly at a later time.
[jsmith@server ~]$ kinit admin [jsmith@server ~]$ ipa host-del server.example.com
- If the system should be re-added to a new IdM domain — such as a virtual machine which was moved from one location to another — then the system can be rejoined to IdM using the
ipa-join
command on the client system.[jsmith@client ~]$ ipa-join
Chapter 6. Upgrading Identity Management
6.1. Upgrade Notes
Important
mod_nss
module. You can ensure that by following these steps:
- Edit the
/etc/httpd/conf.d/nss.conf
file and set theNSSProtocol
parameter toTLSv1.0
(for backward compatibility) andTLSv1.1
.NSSProtocol TLSv1.0,TLSv1.1
- Restart the
httpd
service.# service httpd restart
- The update process automatically updates all schema and LDAP configuration, Apache configuration, and other services configuration, and restarts all IdM-associated services.
- When a replica is created, it must be the same version as the master it is based on. This means that replicas should not be created on an older bersion of Identity Management while the servers are in the process of being upgraded. Wait until the upgrade process is completed, and then create new replicas.
- Schema changes are replicated between servers. So once one master server is updated, all servers and replicas will have the updated schema, even if their packages are not yet updated. This ensures that any new entries which use the new schema can still be replicated among all the servers in the IdM domain.The LDAP upgrade operation is logged in the upgrade log at
/var/log/ipaupgrade-log
. If any LDAP errors occur, then they are recorded in that log. Once any errors are resolved, the LDAP update process can be manually initiated by running the updater script:[root@server ~]# ipa-ldap-updater --upgrade
- Clients do not need to have new packages installed. The client packages used to configure a Red Hat Enterprise Linux system do not impact the enrollment of the client within the domain.
- Updating client packages could bring in updated packages for other dependencies, such as
certmonger
which contain bug fixes, but this is not required to maintain client functionality or behavior within the IdM domain.
6.2. Upgrading Packages
[root@ipaserver ~]# yum update
yum
on the master server:
[root@ipaserver ~]# yum update ipa-server
Note
6.3. Removing Browser Configuration for Ticket Delegation (For Upgrading from 6.2)
delegation-uris
parameter to the about:config
setup in Firefox:
network.negotiate-auth.delegation-uris .example.com
For browsers which have already been configured to use the Identity Management web UI, the delegation-uris
setting can be cleared after upgrading to ipa-server-3.0.0
or ipa-client-3.0.0
.
delegation-uris
setting.
The browser configuration is defined in the configure.jar
file. This JAR file is generated when the server is installed and it is not updated with other files when IdM is updated. Any browsers configured will still have the delegation-uris
parameter set unnecessarily, even after the IdM server is upgraded. However, the configure.jar
file can be updated.
preferences.html
file in configure.jar
sets the delegation-uris
parameter. The updated preferences.html
file can be added to configure.jar
, and then configure.jar
can be re-signed and re-deployed on the IdM servers.
Note
configure.jar
file on the initial IdM server. This is the master server, and it is the only server which has a signing certificate. Then propagate the updated file to the other servers and replicas.
- Update the packages on the initial IdM master server (the first instance). This will bring in the 3.0 UI packages, including the
configure.jar
file. - Back up the existing
configure.jar
file.[root@ipaserver ~]# mv /usr/share/ipa/html/configure.jar /usr/share/ipa/html/configure.jar.old
- Create a temporary working directory.
[root@ipaserver ~]# mkdir /tmp/sign
- Copy the updated
preferences.html
file to the working directory.[root@ipaserver ~]# cp /usr/share/ipa/html/preferences.html /tmp/sign
- Use the
signtool
command (one of the NSS utilities) to add the newpreferences.html
file and re-sign theconfigure.jar
file.[root@ipaserver ~]# signtool -d /etc/httpd/alias -k Signing-Cert -Z /usr/share/ipa/html/configure.jar -e ".html" -p `cat /etc/httpd/alias/pwdfile.txt` /tmp/sign
The-e
option tells the tool to sign only files with a.html
extension. The-Z
option creates a new JAR file. - Copy the regenerated
configure.jar
file to all other IdM servers and replicas.
6.4. Testing Before Upgrading the IdM Server (Recommended)
- Set up a replica based on one of the production servers, with the same version of IdM as is running in production, as described in Chapter 4, Setting up IdM Replicas. For this example, this is called Test Replica. Make sure that Test Replica can successfully connect to the production server and domain.
- After verifying that Test Replica has been successfully added to the production domain, disconnect Test Replica from the network.
- Remove the replication agreements for Test Replica from the original IdM server and from Test Replica.
- Reconnect Test Replica to the network.
- Upgrade the packages on Test Replica using
yum
or whatever package update tool is appropriate for your system. For example:[root@ipareplica ~]# yum update ipa*
- Test common things on Test Replica, like getting Kerberos credentials, opening the server UI, and running commands.
Chapter 7. Uninstalling IdM Servers and Replicas
--uninstall
option to the ipa-server-install
command:
[root@ipareplica ~]# ipa-server-install --uninstall
Chapter 8. The Basics of Managing the IdM Server and Services
8.1. Starting and Stopping the IdM Domain
service
command. However, when multiple domain services need to be restarted (or the entire IdM server), then use the ipactl
command, which always starts and stops services in the appropriate order.
ipactl
command can start, stop, and restart services.
ipactl start | stop | restart
chkconfig
command sets what services to start automatically when the system restarts. The ipactl
command can be used to start the domain services in the proper order, without having to configure each one individually in the chkconfig
run order.
[root@server ~]# chkconfig ipactl on
8.2. About the IdM Client Tools
ipa
. This script is a parent or control script for associated subcommands; each subcommand relates to a specific entry type.
- The scripts allow management tasks to be automated and performed repeatedly in a consistent way without manual intervention.
- Entries can be added with all possible attributes configured (or a desired subset of attributes) in a single step. The web UI frequently requires two steps to fully configure an entry: the first to create the entry and the next to add optional attributes.
- The command-line scripts support adding additional attributes which may not be available in the UI or even custom attributes to entries, if the schema is configured.
8.2.1. The Structure of the ipa Command
ipa
command is essentially a big plug-in container. It supports dozens of subcommands; these subcommands are actually plug-ins which manage specific types of objects in Identity Management.
ipa objectType-operation objectName --option=value
user-add
subcommand:
ipa user-add entryName options
dnszone-add
and dnsrecord-add
all belong to the dns module or topic. All of the information for managing a specific area, with all of the supported commands and examples for each, are available by viewing the help for that topic:
ipa help topic
Note
ipa help topics
8.2.1.1. Adding, Editing, and Deleting Entries with ipa
$ ipa user-add jsmith
add
operations, commands usually prompt for any required configuration attributes, which can be passed as command-line options or using --set/addattr
options (Section 8.2.3, “Managing Entry Attributes with --setattr, --addattr, and --delattr”).
$ ipa user-add First name: John Last name: Smith User login [jsmith]: jsmith -------------------- Added user "jsmith" -------------------- ...
*-mod
commands, and then any new or edited attributes are listed as options after it.
$ ipa user-mod jsmith --title="Editor III"
*-del
command and the entry's name.
$ ipa user-del jsmith
8.2.1.2. Finding and Displaying Entries with ipa
*-find
command and an optional search criterion. The criterion is a string which can either be an exact match or a substring of any of the search attribute values. For example, this searches both for the exact match on the string smith (such as an sn
value of Smith) and a substring search for values such as a username of jsmith or a longer surname, such as Smithson.
ipa user-find smith
*-find
command) have certain limits imposed as part of the server configuration, specifically how many entries are returned (size limits) and how long a search will run (time limits). This is covered in Section 9.11.3.1.2, “Setting IdM Search Limits”. Part of the server configuration is setting global defaults for size and time limits on searches. While these limits are always enforced in the web UI, they can be overridden with any *-find
command with the --sizelimit
and --timelimit
options. For example, if the default time limit is 60 seconds and a search is going to take longer, the time limit can be increased to 120 seconds:
[jsmith@ipaserver ~]$ ipa user-find smith --timelimit=120
--all
option.
*-show
command and the entry name. As with searches, only a subset of attributes is displayed with the entry unless the --all
option is used.
8.2.1.3. Adding Members to Groups and Containers with ipa
*-add-member
, although the command may specify an entry type, such as *-add-user
.
*-remove-member
or *-remove-
type command.
8.2.2. Positional Elements in ipa Commands
ipa
subcommands have only two elements: the name of the entry being modified (the object) and then any options available for the subcommand:
ipa command entryName --options=values
automount
commands, for example. With automount, the location must be included whenever a new key or map is created.
ipa command parentEntryName childEntryName --childOptions=childValues
8.2.3. Managing Entry Attributes with --setattr, --addattr, and --delattr
ipa
command uses specified command-line arguments to set values. For example, adding a mail attribute to a user can be done with the --mail
argument; enabling dynamic updates for a DNS zone can be done with the --allow-dynupdate
option with zone commands; and a map key for an automount map is given in the --key
option.
--setattr
and --addattr
options.
Important
--setattr
or --addattr
options.
--setattr=attribute=value
--setattr
option sets one value for the given attribute; any existing values are overwritten, even for multi-valued attributes.
--addattr
option adds a new value for an attribute; for a multi-valued attribute, it adds the new value while preserving any existing values.
--setattr
option and --addattr
can be used multiple times in the same command invocation. For example:
$ ipa user-mod jsmith --addattr=mail=johnnys@me.com --addattr=mail=jsmith@example.com --setattr=description="backup IT manager for the east coast branch"
--delattr
option. For a single-valued attribute, this removes the attribute; for a multi-valued attribute, it removes only the specified value. For example:
$ ipa user-mod jsmith --delattr=mail=johnnys@me.com
Note
$ ipa user-mod jsmith --addattr=mail=johnnys@me.com --delattr=mail=johnnys@me.com
8.2.4. Using Special Characters with IdM Tools
8.2.5. Logging into the IdM Domain Before Running
ipa-server-install
), the user must first authenticate to the IdM domain by obtaining a Kerberos ticket. This is done using kinit
:
[jsmith@ipaserver ~]$ kinit admin
8.3. Logging into IdM
kinit
.
kinit
issues the user a Kerberos ticket. This ticket is checked by any IdM or Kerberos-aware service, so that a user only needs to log in once to access all domain services. Domain services include the IdM web UI, mounted file shares, wikis, or any other application which uses IdM as its identity/authentication store.
8.3.1. Logging into IdM
kinit
on a client within the IdM domain.
$ kinit
kinit
command must be run from a machine which has been configured as a client within the IdM domain, so that the client authenticates with the IdM KDC.
kinit
logs into IdM as the currently logged-in user account. This user account must also be an IdM user for them to authenticate to the IdM Kerberos domain successfully. For example, if you are logged into the machine as user
:
$ kinit Password for user@EXAMPLE.COM:
Note
pam_krb5
is configured on the IdM client machine, then when a user logs into the machine, a ticket is created which can be used for machine services which require authentication, such as sudo
.
8.3.2. Logging in When an IdM User Is Different Than the System User
kinit
command again and specify the new user. For example:
$ kinit userName Password for userName@EXAMPLE.COM:
admin
, is created to perform normal administrative activities. To authenticate as the admin user, use the name admin when running kinit
:
$ kinit admin
Note
8.3.3. Checking the Current Logged in User
klist
command to verify the identity and the ticket granting ticket (TGT) from the server:
$ klist Ticket cache: FILE:/tmp/krb5cc_500 Default principal: ipaUser@EXAMPLE.COM Valid starting Expires Service principal 11/10/08 15:35:45 11/11/08 15:35:45 krbtgt/EXAMPLE.COM@EXAMPLE.COM Kerberos 4 ticket cache: /tmp/tkt500 klist: You have no tickets cached
kinit
have some limitation, one of them being that the current ticket is overwritten with any new invocation of kinit
. Authenticating as User A and then authenticating as User B overwrites User A's ticket.
KRB5CCNAME
environment variable. This variable keeps credential caches separate in different shells.
8.3.4. Caching User Kerberos Tickets
admin
, added a new user, set the password, and then tried to authenticate as that user, the administrator's ticket is lost.
KRB5CCNAME
, can be used.
8.4. Using the IdM Web UI
8.4.1. About the Web UI
Main Menu Tab | Configuration Areas |
---|---|
Identity |
|
Policy |
|
IdM Server (access controls within Identity Management) |
|
Figure 8.1. The Main Menu
8.4.2. Opening the IdM Web UI
- Get a valid Kerberos ticket using
kinit
, as in Section 8.3, “Logging into IdM”. - Open the IdM URL. The full URL is
https://
IPAserver-FQDN/ipa/ui
, but this service is also accessed simply by openinghttps://
IPAserver-FQDN. For example:https://server.example.com https://server.example.com/ipa/ui
8.4.3. Configuring the Browser
8.4.3.1. Configuring Firefox
Figure 8.2. Kerberos Authentication Error
- Click the follow these directions link.
- Click the link to import the CA certificate for the IdM server.
- Set the web site and software developer (first and last) trust bits for the CA certificate.
- Click the Configure Firefox button. This automatically fills out all the
negotiate
settings in the Firefox configuration to use the IdM domain settings.When the process is complete, a success box pops up saying that Firefox has been configured for single sign-on. From there, you are redirected to the IdM web UI.
- Start Firefox.
- Type
about:config
in the address bar. - In the Search field, type
negotiate
to filter out the Kerberos-related parameters. - On Red Hat Enterprise Linux, enter the domain name for the URI parameters, including the preceding period (.) and set the
gsslib
parameter to true:network.negotiate-auth.trusted-uris .example.com network.negotiate-auth.using-native-gsslib true
On Windows, set the trusted URIs and library path, and disable the built-in Microsoft Kerberos for authentication:network.negotiate-auth.trusted-uris .example.com network.auth.use-sspi false network.negotiate-auth.gsslib: C:\Program Files\MIT\Kerberos\bin\gssapi32.dll
On a 64-bit system, the library location is inC:\Program Files(x86)\MIT\Kerberos\bin\gssapi32.dll
. - Open the web UI by going to the fully-qualified domain name of the IdM server such as
http://ipaserver.example.com
. Make sure that you can open the web UI and that there are no Kerberos authentication errors. - Next, download the IdM server's CA certificate from
http://ipa.example.com/ipa/config/ca.crt
. - In the Downloading Certificate window that appears, select the first (Trust this CA to identify web sites) and third (Trust this CA to identify software developers) check boxes.
8.4.3.2. Configuring Chrome
- Import CA Certificate
- Download the CA certificate from
http://my.ipa.server/ipa/config/ca.crt
. Alternatively, if the host is also an IdM client, you can find the certificate in/etc/ipa/ca.crt
. - Click the menu button with the
Customize and control Google Chrome
tooltip, which is by default in the top right-hand corner of Chrome, and click Settings. - Click Show advanced settings to display more options, and then click the Manage certificates button located under the
HTTPS/SSL
heading. - In the Authorities tab, click the Import button at the bottom.
- Select the CA certificate file that you downloaded in the first step.
- Enable SPNEGO (Simple and Protected GSSAPI Negotiation Mechanism) to Use Kerberos Authentication in Chrome
- Make sure you have the necessary directory created by running
[root@client]# mkdir -p /etc/opt/chrome/policies/managed/
- Create a new
/etc/opt/chrome/policies/managed/mydomain.json
file with write privileges limited to the system administrator or root, and include the following line:{ "AuthServerWhitelist": "*.example.com" }
You can do this by running[root@server]# echo '{ "AuthServerWhitelist": "*.example.com" }' > /etc/opt/chrome/policies/managed/mydomain.json
8.4.4. Using a Browser on Another System
kinit
, and then the user can authenticate against the IdM server domain.
- Copy the
/etc/krb5.conf
file from the IdM server.# scp /etc/krb5.conf root@externalmachine.example.com:/etc/krb5_ipa.conf
Warning
Do not overwrite the existingkrb5.conf
file. - On the external machine, set the terminal session to use the copied IdM Kerberos configuration file:
$ export KRB5_CONFIG=/etc/krb5_ipa.conf
- Configure Firefox on the external machine as in Section 8.4.3, “Configuring the Browser”.
8.4.5. Logging in with Simple Username/Password Credentials
Figure 8.3. IdM Form-Based Login Option
Figure 8.4. IdM Password Prompt
8.4.6. Using the UI with Proxy Servers
8.5. Configuring an IdM Server to Run in a TLS 1.2 Environment
/etc/ipa/default.conf
configuration file.
Chapter 9. Identity: Managing Users and User Groups
9.1. Setting up User Home Directories
9.1.1. About Home Directories
- The default prefix for users' home directories is
/home
. - IdM does not automatically create home directories when users log in. Automatically creating home directories requires either the
pam_oddjob_mkhomedir
module or thepam_mkhomedir
module. This module can be configured as part of client installation or after installation, as described in Section 9.1.2, “Enabling the PAM Home Directory Module”.The home directory process for IdM first attempts to use thepam_oddjob_mkhomedir
module because this requires fewer user privileges and access to create the home directories, as well as integrating smoothly with SELinux. If this module is not available, then the process falls back to thepam_mkhomedir
module.Note
On Red Hat Enterprise Linux 5 clients, the client installation script uses thepam_mkhomedir
module even if thepam_oddjob_mkhomedir
module is available. To use thepam_oddjob_mkhomedir
module on Red Hat Enterprise Linux 5, edit the PAM configuration manually. - It is possible to use an NFS file server that provides
/home
that can be made available to all machines in the domain and then automounted on the IdM server.There are potential issues when using NFS, such as security issues related to granting root access to the NFS user, performance issues with loading the entire/home
tree, and network performance issues for using remote servers for home directories. There are some general guidelines for using NFS with Identity Management:- Use automount to mount only the user's home directory and only when the user logs in, rather than loading the entire
/home
tree. - Use a remote user who has limited permissions to create home directories and mount the share on the IdM server as that user. Since the IdM server runs as an
httpd
process, it is possible to usesudo
or a similar program to grant limited access to the IdM server to create home directories on the NFS server. - Use a mechanism, such as the
pam_oddjob_mkhomedir
module, to create the home directory as that user.
Using automounts for home directories is described in Section 9.1.3, “Manually Mounting Home Directories”. - If a suitable directory and mechanism are not available to create home directories, users may not be able to log in.
9.1.2. Enabling the PAM Home Directory Module
pam_oddjob_mkhomedir
module or the pam_mkhomedir
module. Because it requires fewer permissions and works well with SELinux, IdM preferentially uses the pam_oddjob_mkhomedir
module. If that module is not installed, then it falls back to the pam_mkhomedir
module.
Note
pam_oddjob_mkhomedir
module or pam_mkhomedir
module. This is because the *_mkhomedir
module may try to create home directories even when the shared storage is not available. If the module is unable to create the home directory, then users can be blocked from logging into the IdM domain.
pam_oddjob_mkhomedir
(or pam_mkhomedir
) module:
- The
--mkhomedir
option can be used with theipa-client-install
command. While this is possible for clients, this option is not available to servers when they are set up. - The
pam_oddjob_mkhomedir
module can be enabled using the system'sauthconfig
command. For example:authconfig --enablemkhomedir --update
This option can be used for both server and client machines post-installation.
Note
pam_mkhomedir
module even if the pam_oddjob_mkhomedir
module is available. To use the pam_oddjob_mkhomedir
module on Red Hat Enterprise Linux 5, edit the PAM configuration manually.
9.1.3. Manually Mounting Home Directories
automount
.
- Create a new location for the user directory maps:
[bjensen@server ~]$ ipa automountlocation-add userdirs Location: userdirs
- Add a direct map to the new location's
auto.direct
file. In this example, the mount point is/share
:[bjensen@server ~]$ ipa automountkey-add userdirs auto.direct --key=/share --info="-ro,soft, ipaserver.example.com:/home/share" Key: /share Mount information: -ro,soft, ipaserver.example.com:/home/share
9.2. Managing User Entries
9.2.1. About Username Formats
[a-zA-Z0-9_.][a-zA-Z0-9_.-]{0,252}[a-zA-Z0-9_.$-]?
Note
Note
9.2.2. Adding Users
9.2.2.1. From the Web UI
- Open the Identity tab, and select the Users subtab.
- Click the Add link at the top of the users list.
- Fill in the user's first and last names. The user login (UID) is automatically generated based on the user's full name, but this can be set manually by clicking the Optional field link.
Note
Usernames are case insensitive when they are created, meaning that case is ignored. Username are automatically normalized to be all lower case, even if the user is created with mixed case or upper case letters. - Click the Add and Edit button to go directly to the expanded entry page and fill in more attribute information, as in Section 9.2.3.1, “From the Web UI”. The user entry is created with some basic information already filled in, based on the given user information and the user entry template.
9.2.2.2. From the Command Line
user-add
command. Attributes (listed in Table 9.2, “Default Identity Management User Attributes”) can be added to the entry with specific values or the command can be run with no arguments.
[bjensen@server ~]$ ipa user-add [username] [attributes]
[bjensen@server ~]$ ipa user-add First name: John Last name: Smith User login [jsmith]: jsmith -------------------- Added user "jsmith" -------------------- User login: jsmith First name: John Last name: Smith Full name: John Smith Display name: John Smith Initials: JS Home directory: /home/jsmith GECOS: John Smith Login shell: /bin/sh Kerberos principal: jsmith@EXAMPLE.COM Email address: jsmith@example.com UID: 882600007 GID: 882600007 Password: False Member of groups: ipausers Kerberos keys available: False
[bjensen@server ~]$ ipa user-add jsmith --first=John --last=Smith --manager=bjensen --email=johnls@example.com --homedir=/home/work/johns --password
Note
Important
uidNumber
is unique. It will allow duplicate IDs; this is expected (though discouraged) behavior for POSIX entries.
ipa user-find --all
.
9.2.3. Editing Users
9.2.3.1. From the Web UI
- Open the Identity tab, and select the Users subtab.
- Click the name of the user to edit.
- There are a number of different types of attributes that can be edited for the user. All of the default attributes are listed in Table 9.2, “Default Identity Management User Attributes”. Most of the attributes in the Identity Settings and Account Settings areas have default values filled in for them, based on the user information or on the user entry template.
- Edit the fields or, if necessary, click the Add link by an attribute to create the attribute on the entry.
- When the edits are done, click the Update link at the top of the page.
9.2.3.2. From the Command Line
user-mod
command edits user accounts by adding or changing attributes. At its most basic, the user-mod
specifies the user account by login ID, the attribute to edit, and the new value:
[bjensen@server ~]$ ipa user-mod loginID --attributeName=newValue
[bjensen@server ~]$ ipa user-mod jsmith --title="Editor III"
--addattr
option.
--setattr
. However, using --addattr
will add a new attribute; for a multi-valued attribute, it adds the new value in addition to any existing values.
Example 9.1. Multiple Mail Attributes
[bjensen@server ~]$ ipa user-add jsmith --first=John --last=Smith --email=johnls@example.com
[bjensen@server ~]$ ipa user-mod jsmith --addattr=mail=johnnys@me.com
[bjensen@server ~]$ ipa user-find jsmith --all
--------------
1 user matched
--------------
dn: uid=jsmith,cn=users,cn=accounts,dc=example,dc=com
User login: jsmith
.....
Email address: jsmith@example.com, jsmith@new.com
--addattr
option twice:
[bjensen@server ~]$ ipa user-add jsmith --first=John --last=Smith --email=johnls@example.com --addattr=mail=johnnys@me.com --addattr=mail=admin@example.com
9.2.4. Deleting Users
Note
9.2.4.1. With the Web UI
- Open the Identity tab, and select the Users subtab.
- Select the checkboxes by the names of the users to delete.
- Click the Delete link at the top of the task area.
- When prompted, confirm the delete action.
9.2.4.2. From the Command Line
user-del
command and then the user login. For example, a single user:
[bjensen@server ~]$ ipa user-del jsmith
[bjensen@server ~]$ ipa user-del jsmith bjensen mreynolds cdickens
--continue
option to force the command to continue regardless of errors. A summary of the successful and failed operations is printed to stdout when the command completes. If --continue
is not used, then the command proceeds with deleting users until it encounters an error, and then it exits.
9.3. Managing Public SSH Keys for Users
authorized_keys
file. Any time that the user attempts to access the resource again, the machine simply checks its authorized_keys
file and then grants access automatically to approved users.
- SSH keys have to be distributed manually and separately to all machines in an environment.
- Administrators have to approve user keys to add them to the configuration, but it is difficult to verify either the user or key issuer properly, which can create security problems.
9.3.1. About the SSH Key Format
id_rsa.pub
, a key entry is identified by its type, then the key itself, and then an additional comment or identifier. For example, for an RSA key associated with a specific hostname:
"ssh-rsa ABCD1234...== ipaclient.example.com"
9.3.2. Uploading User SSH Keys Through the Web UI
- Generate a user key. For example, using the OpenSSH tools:
[jsmith@server ~]$ ssh-keygen -t rsa -C jsmith@example.com Generating public/private rsa key pair. Enter file in which to save the key (/home/jsmith/.ssh/id_rsa): Created directory '/home/jsmith/.ssh'. Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /home/jsmith/.ssh/id_rsa. Your public key has been saved in /home/jsmith/.ssh/id_rsa.pub. The key fingerprint is: a5:fd:ac:d3:9b:39:29:d0:ab:0e:9a:44:d1:78:9c:f2 jsmith@example.com The key's randomart image is: +--[ RSA 2048]----+ | | | + . | | + = . | | = + | | . E S.. | | . . .o | | . . . oo. | | . o . +.+o | | o .o..o+o | +-----------------+
- Copy the public key from the key file. The full key entry has the form type key== comment. Only the key== is required, but the entire entry can be stored.
[jsmith@server ~]$ cat /home/jsmith/.ssh/id_rsa.pub ssh-rsa AAAAB3NzaC1yc2E...tJG1PK2Mq++wQ== jsmith@example.com
- Open the Identity tab, and select the Users subtab.
- Click the name of the user to edit.
- In the Account Settings area of the Settings tab, click the SSH public keys: Add link.
- Click the Add link by the SSH public keys field.
- Paste in the public key for the user, and click thebutton.The SSH public keys field now shows New: key set. Clicking the Show/Set key link opens the submitted key.
- To upload multiple keys, click the Add link below the list of public keys, and upload the other keys.
- When all the keys have been submitted, click the Update link at the top of the user's page to save the changes.
Figure 9.1. Saved Public Key
9.3.3. Uploading User SSH Keys Through the Command Line
--sshpubkey
option uploads the 64 bit-encoded public key to the user entry. For example:
[jsmith@server ~]$ ipa user-mod jsmith --sshpubkey="ssh-rsa 12345abcde= ipaclient.example.com"
--sshpubkey
option:
--sshpubkey="12345abcde==,key2==,key3=="
9.3.4. Deleting User Keys
- Open the Identity tab, and select the Users subtab.
- Click the name of the user to edit.
- Open the Account Settings area of the Settings tab.
- Click the Delete link by the fingerprint of the key to remove.
- Click the Update link at the top of the user's page to save the changes.
ipa user-mod
with the --sshpubkey=
set to a blank value; this removes all public keys for the user. For example:
[jsmith@server ~]$ kinit admin [jsmith@server ~]$ ipa user-mod --sshpubkey= jsmith
9.4. Changing Passwords
- Regular, non-administrative users can change only their personal passwords, and all passwords are constrained by the IdM password policies.This allows administrators to create intro passwords or to reset passwords easily, while still keeping the final password confidential. Since any password sent by an administrator to the user is temporary, there is little security risk.
- Changing a password as the IdM admin user overrides any IdM password policies, but the password expires immediately. This requires the user to change the password at the next login. Similarly, any user who has password change rights can change a password and no password policies are applied, but the other user must reset the password at the next login.
- Changing a password as the LDAP Directory Manager user, using LDAP tools, overrides any IdM password policies.
9.4.1. From the Web UI
- Open the Identity tab, and select the Users subtab.
- Click the name of the user for whom to reset the password. All users can change their own password; only administrators or users with delegated permissions can change other user's passwords.
- Scroll to the Account Settings area.
- Click the Reset Password link.
- In the pop-up box, enter and confirm the new password.
9.4.2. From the Command Line
user-mod
command, as with other user account changes.
[bjensen@ipaserver ~]$ kinit admin [bjensen@ipaserver ~]$ ipa user-mod jsmith --password
9.5. Enabling and Disabling User Accounts
Note
9.5.1. From the Web UI
Figure 9.2. Disable/Enable Options at the Top of the Users List
- Open the Identity tab, and select the Users subtab.
- Click the name of the user to deactivate or activate.
- In the actions drop-down menu, select the Disable item.
- Click the Accept button.
Figure 9.3. Disable Icon for User Status
9.5.2. From the Command Line
user-enable
and user-disable
commands. All that is required is the user login. For example:
[bjensen@server ~]$ ipa user-disable jsmith
9.6. Unlocking User Accounts After Password Failures
user-unlock
command. For example:
[bjensen@ipaserver ~]$ kinit admin [bjensen@ipaserver ~]$ ipa user-unlock jsmith
9.7. Smart Cards
9.7.1. Smart Card and Smart Card Reader Support in Identity Management
/etc/pki/nssdb/
NSS database after the installation of these packages.
- Add the required PKCS #11 module manually using the
modutil
utility. For example:[root@ipaclient ~]# modutil -dbdir /etc/pki/nssdb/ -add "My PKCS#11 module" -libfile libmypkcs11.so ... Module "My PKCS#11 Module" added to database.
For detailed information on usingmodutil
, see the modutil(1) man page. - Add all certificate authority (CA) certificates to the NSS database that are required to validate the certificate on the smart card. For example, to add the CA certificate in the
ca_certificate.pem
file to the NSS database:[root@ipaclient ~]# certutil -A -d /etc/pki/nssdb/ -n 'CA certificate' -t CT,C,C -a -i ca_certificate.pem
For detailed information on usingcertutil
, see the certutil(1) man page.
9.7.2. Exporting a Certificate From a Smart Card
- Place the smart card into the reader.
- Run the following command to list the certificates on the smart card:
[user@ipaclient ~]$ certutil -L -d /etc/pki/nssdb/ -h all Certificate Nickname Trust Attributes SSL,S/MIME,JAR/XPI my_certificate CT,C,C
In the output, locate the certificate to use for authentication, and note its nickname. - To extract the certificate in Base64 format to
user.crt
, use the nickname from the previous step:[user@ipaclient ~]$ certutil -L -d /etc/pki/nssdb/ -n 'my_certificate' -r | base64 -w 0 > user.crt
Thebase64
utility is part of the coreutils package.
9.7.3. Storing Smart Card Certificates for IdM Users
9.7.4. Smart Card Authentication on Identity Management Clients
- Local authentication
- Text console
- Graphical console, such as the Gnome Display Manager (GDM)
- Local authentication services, like
su
, orsudo
- Remote authentication with
ssh
- Certificates on a smart card are stored together with the PIN-protected SSH private key.
Note
ssh
for smart card authentication. Other services, such as FTP, are not supported.
9.7.4.1. Configuring Smart Card Authentication on an IdM Client
- To enable smart card support, allow SSSD to prompt for password, one-time password (OTP), or the smart card PIN. To do this, modify the
auth
lines of the/etc/pam.d/password-auth
and/etc/pam.d/system-auth
PAM configuration files.- Remove the following lines of the default
/etc/pam.d/password-auth
:auth required pam_env.so auth sufficient pam_unix.so nullok try_first_pass auth requisite pam_succeed_if.so uid >= 500 quiet auth sufficient pam_sss.so use_first_pass auth required pam_deny.so
Replace them with these lines:auth required pam_env.so auth [default=1 success=ok] pam_localuser.so auth [success=done ignore=ignore default=die] pam_unix.so nullok try_first_pass auth requisite pam_succeed_if.so uid >= 500 quiet auth sufficient pam_sss.so forward_pass auth required pam_deny.so
- Similarly, remove the following lines of the default
/etc/pam.d/system-auth
:auth required pam_env.so auth sufficient pam_unix.so nullok try_first_pass auth requisite pam_succeed_if.so uid >= 500 quiet auth sufficient pam_sss.so use_first_pass auth required pam_deny.so
Replace them with these lines:auth required pam_env.so auth [default=1 success=ok] pam_localuser.so auth [success=done ignore=ignore default=die] pam_unix.so nullok try_first_pass auth requisite pam_succeed_if.so uid >= 500 quiet auth sufficient pam_sss.so forward_pass auth required pam_deny.so
- Set the following option in your
/etc/sssd/sssd.conf
totrue
:[pam] pam_cert_auth=true
- Restart SSSD:
[root@ipaclient ~]# systemctl restart sssd
9.7.4.2. SSH Log in Using a Smart Card
ssh
when authenticating with a smart card, you have to additionally specify the following path to the smart card reader module. For example:
$ ssh -I /usr/lib/libmypkcs11.so -l user@example.com host.example.com Enter PIN for 'Smart Card':
9.8. Managing User Private Groups
umask
defaults only have to restrict user access, not group access.
9.8.1. Listing User Private Groups
--private
option with the group-find command. For example:
[root@server ~]# ipa group-find --private --------------- 1 group matched --------------- Group name: jsmith Description: User private group for jsmith GID: 1084600001 ---------------------------- Number of entries returned 1 ----------------------------
9.8.2. Disabling Private Groups for a Specific User
--noprivate
option.
ipausers
) is a non-POSIX group and, therefore, does not have an associated GID. So that the add operation does not fail, it is necessary either to set an explicit user GID with the --gid
option or to create a group with a GID and add the user to that group using an automembership rule (covered in Chapter 25, Policy: Defining Automatic Group Membership for Users and Hosts).
[jsmith@server ~]$ ipa user-add jsmith --first=John --last=Smith --noprivate
--gid 10000
9.8.3. Disabling Private Groups Globally
ipa-managed-entries
command.
- Use the
ipa-managed-entries
command to list possible Managed Entries Plug-in definitions. By default, there are two, one for new users (UPG) and one for netgroups (NGP).[root@ipaserver ~]# ipa-managed-entries --list -p DMpassword Available Managed Entry Definitions: UPG Definition NGP Definition
- Disable the desired Managed Entries Plug-in instance. For example:
[root@ipaserver ~]# ipa-managed-entries -e "UPG Definition" -p DMpassword disable Disabling Plugin
- Restart the 389 Directory Server to load the new plug-in configuration.
[root@ipaserver ~]# service dirsrv restart
enable
option.
9.9. Managing Unique UID and GID Number Assignments
9.9.1. About ID Number Ranges
uidNumber
) and group IDs (gidNumber
). A user and a group may have the same ID, but since the ID is set in different attributes, there is no conflict. Using the same ID number for both a user and a group also allows an administrator to configure user private groups, where a unique system group is created for each user and the ID number is the same for both the user and the group.
Important
uidNumber
is unique. It will allow duplicate IDs; this is expected (though discouraged) behavior for POSIX entries. The same is true for group entries: a duplicate gidNumber
can be manually assigned to the entry.
ipa user-find --all
.
9.9.2. About ID Range Assignments During Installation
--idstart
and --idmax
options with ipa-server-install
. These options are not required, so the setup script can assign random ranges during installation.
9.9.3. A Note on Conflicting ID Ranges
min_id
and max_id
options in the sssd.conf
file. The default min_id
value is 1
. However, Red Hat recommends to set this value to 1000
in order to avoid conflicts with UID and GID numbers that are reserved for system use.
9.9.4. Adding New Ranges
dnaNextRange
parameter. For example:
ldapmodify -x -D "cn=Directory Manager" -W -h server.example.com -p 389 Enter LDAP Password: ******* dn: cn=POSIX IDs,cn=Distributed Numeric Assignment Plugin,cn=plugins,cn=config changetype: modify add: dnaNextRange dnaNextRange: 123400000-123500000
Note
9.9.5. Repairing Changed UID and GID Numbers
Important
[root@server ~]# sss_cache -u jsmith
9.10. Managing User and Group Schema
Description | Object Classes | |||||
---|---|---|---|---|---|---|
IdM object classes |
| |||||
Person object classes |
| |||||
Kerberos object classes |
| |||||
Managed entries (template) object classes | mepOriginEntry |
UI Field | Command-Line Option | Required, Optional, or Default[a] |
---|---|---|
User login | username | Required |
First name | --first | Required |
Last name | --last | Required |
Full name | --cn | Optional |
Display name | --displayname | Optional |
Initials | --initials | Default |
Home directory | --homedir | Default |
GECOS field | --gecos | Default |
Shell | --shell | Default |
Kerberos principal | --principal | Default |
Email address | Optional | |
Password | --password [b] | Optional |
User ID number[c] | --uid | Default |
Group ID number[c] | --gidnumber | Default |
Street address | --street | Optional |
City | --city | Optional |
State/Province | --state | Optional |
Zip code | --postalcode | Optional |
Telephone number | --phone | Optional |
Mobile telephone number | --mobile | Optional |
Pager number | --pager | Optional |
Fax number | --fax | Optional |
Organizational unit | --orgunit | Optional |
Job title | --title | Optional |
Manager | --manager | Optional |
Car license | --carlicense | Optional |
--noprivate | Optional | |
SSH Keys | --sshpubkey | Optional |
Additional attributes | --addattr | Optional |
[a]
Required attributes must be set for every entry. Optional attributes may be set, while default attributes are automatically added with a pre-defined value unless a specific value is given.
[b]
The script prompts for the new password, rather than accepting a value with the argument.
[c]
When a user is created without specifying a UID number, then the user account is automatically assigned an ID number that is next available in the server or replica range. (Number ranges are described more in Section 9.9, “Managing Unique UID and GID Number Assignments”.) This means that a user always has a unique number for its UID number and, if configured, for its private group.
If a number is manually assigned to a user entry, the server does not validate that the uidNumber is unique. It will allow duplicate IDs; this is expected (though discouraged) behavior for POSIX entries.
If two entries are assigned the same ID number, only the first entry is returned in a search for that ID number. However, both entries will be returned in searches for other attributes or with ipa user-find --all .
|
9.10.1. About Changing the Default User and Group Schema
- All of the object classes and their specified attributes must be known to the LDAP server.
- All default attributes that are configured for the entry must be supported by the configured object classes.
ipaobject
object class. However, when the user or group schema is changed, the server does not check to make sure that this object class is included; if the object class is accidentally deleted, then future entry add operations will fail.
9.10.2. Applying Custom Object Classes to New User Entries
9.10.2.1. From the Web UI
- Add all of the custom schema elements to the 389 Directory Server instance used by Identity Management. Adding schema elements is described in the schema chapter of the Directory Server Administrator's Guide.
- Open the IPA Server tab.
- Select the Configuration subtab.
- Scroll to the User Options area.
- At the bottom of the users area, click the Add link to add a new field for another object class.
Important
Always include the existing default object classes when the configuration is updated. Otherwise, the current settings will be overwritten. If any object classes required by Identity Management are not included, then subsequent attempts to add an entry will fail with object class violations. - When the changes are complete, click the Update link at the top of the Configuration page.
9.10.2.2. From the Command Line
- Add all of the custom schema elements to the 389 Directory Server instance used by Identity Management. Adding schema elements is described in the schema chapter of the Directory Server Administrator's Guide.
- Add the new object class to the list of object classes added to entries. The option for user object classes is
--userobjectclasses
.Important
Always include the existing default object classes when the configuration is updated. Otherwise, the current settings will be overwritten. If any object classes required by Identity Management are not included, then subsequent attempts to add an entry will fail with object class violations.For example:[bjensen@server ~]$ ipa config-mod
--userobjectclasses=
top,person,organizationalperson,inetorgperson,inetuser,posixaccount, krbprincipalaux,krbticketpolicyaux,ipaobject,ipasshuser,employeeinfo
9.10.3. Applying Custom Object Classes to New Group Entries
9.10.3.1. From the Web UI
- Add all of the custom schema elements to the 389 Directory Server instance used by Identity Management. Adding schema elements is described in the schema chapter of the Directory Server Administrator's Guide.
- Open the IPA Server tab.
- Select the Configuration subtab.
- Scroll to the Group Options area.
- Click the Add link to add a new field for another object class.
Important
Always include the existing default object classes when the configuration is updated. Otherwise, the current settings will be overwritten. If any object classes required by Identity Management are not included, then subsequent attempts to add an entry will fail with object class violations. - When the changes are complete, click the Update link at the top of the Configuration page.
9.10.3.2. From the Command Line
- Add all of the custom schema elements to the 389 Directory Server instance used by Identity Management. Adding schema elements is described in the schema chapter of the Directory Server Administrator's Guide.
- Add the new object class to the list of object classes added to entries. The option for group object classes is
--groupobjectclasses
.Important
Always include the existing default object classes when the configuration is updated. Otherwise, the current settings will be overwritten. If any object classes required by Identity Management are not included, then subsequent attempts to add an entry will fail with object class violations.For example:[bjensen@server ~]$ ipa config-mod
--groupobjectclasses=
top,groupofnames,nestedgroup,ipausergroup,ipaobject,ipasshuser,employeegroup
9.10.4. Specifying Default User and Group Attributes
cn=ipaconfig,cn=etc,dc=example,dc=com
.
ipa config-mod
command.
Field | Command-Line Option | Descriptions |
---|---|---|
Maximum username length | --maxusername | Sets the maximum number of characters for usernames. The default value is eight. |
Root for home directories | --homedirectory | Sets the default directory to use for user home directories. The default value is /home . |
Default shell | --defaultshell | Sets the default shell to use for users. The default value is /bin/sh . |
Default user group | --defaultgroup | Sets the default group to which all newly created accounts are added. The default value is ipausers , which is automatically created during the IdM server installation process. |
Default e-mail domain | --emaildomain | Sets the email domain to use to create email addresses based on the new accounts. The default is the IdM server domain. |
Search time limit | --searchtimelimit | Sets the maximum amount of time, in seconds, to spend on a search before the server returns results. |
Search size limit | --searchrecordslimit | Sets the maximum number of records to return in a search. |
User search fields | --usersearch | Sets the fields in a user entry that can be used as a search string. Any attribute listed has an index kept for that attribute, so setting too many attributes could affect server performance. |
Group search fields | --groupsearch | Sets the fields in a group entry that can be used as a search string. |
Certificate subject base | Sets the base DN to use when creating subject DNs for client certificates. This is configured when the server is set up. | |
Default user object classes | --userobjectclasses | Sets a list of object classes that are used to create IdM user accounts. |
Default group object classes | --groupobjectclasses | Sets a list of object classes that are used to create IdM group accounts. |
Password expiration notification | --pwdexpnotify | Sets how long, in days, before a password expires for the server to send a notification. |
Password plug-in features | Sets the format of passwords that are allowed for users. |
9.10.4.1. Viewing Attributes from the Web UI
- Open the IPA Server tab.
- Select the Configuration subtab.
- The complete configuration entry is shown in three sections, one for all search limits, one for user templates, and one for group templates.
9.10.4.2. Viewing Attributes from the Command Line
config-show
command shows the current configuration which applies to all new user accounts. By default, only the most common attributes are displayed; use the --all
option to show the complete configuration.
[bjensen@server ~]$ kinit admin [bjensen@server ~]$ ipa config-show --all dn: cn=ipaConfig,cn=etc,dc=example,dc=com Maximum username length: 32 Home directory base: /home Default shell: /bin/sh Default users group: ipausers Default e-mail domain: example.com Search time limit: 2 Search size limit: 100 User search fields: uid,givenname,sn,telephonenumber,ou,title Group search fields: cn,description Enable migration mode: FALSE Certificate Subject base: O=EXAMPLE.COM Default group objectclasses: top, groupofnames, nestedgroup, ipausergroup, ipaobject Default user objectclasses: top, person, organizationalperson, inetorgperson, inetuser, posixaccount, krbprincipalaux, krbticketpolicyaux, ipaobject, ipasshuser Password Expiration Notification (days): 4 Password plugin features: AllowNThash SELinux user map order: guest_u:s0$xguest_u:s0$user_u:s0$staff_u:s0-s0:c0.c1023$unconfined_u:s0-s0:c0.c1023 Default SELinux user: unconfined_u:s0-s0:c0.c1023 Default PAC types: MS-PAC, nfs:NONE cn: ipaConfig objectclass: nsContainer, top, ipaGuiConfig, ipaConfigObject
9.11. Managing User Groups
- ipausers, which contains all users.
- admins, which contains administrative users. The initial
admin
user belongs to this group. - trusted admins, which contains administrative users used to manage Active Directory trusts.
- editors, which is a special group for users working through the web UI. This group allows users to edit other users' entries, though without all of the rights of the admin user.
Note
9.11.1. Types of Groups in IdM
- Internal groups (the default), where all members belong to the IdM domain.
- External groups, where some or all of the members exist in an identity store outside of the IdM domain. This can be a local system, an Active Directory domain, or a directory service.
posixgroup
object class).
9.11.2. Group Object Classes
Description | Object Classes | |||
---|---|---|---|---|
IdM object classes |
| |||
Group object classes | groupofnames |
9.11.2.1. Creating User Groups
9.11.2.1.1. With the Web UI
- Open the Identity tab, and select the User Groups subtab.
- Click the Add link at the top of the groups list.
- Enter all of the information for the group.
- A unique name. This is the identifier used for the group in the IdM domain, and it cannot be changed after it is created. The name cannot contain spaces, but other separators like an underscore (_) are allowed.
- A text description of the group.
- Whether the group is a POSIX group, which adds Linux-specific information to the entry. By default, all groups are POSIX groups unless they are explicitly configured not to be. Non-POSIX groups can be created for interoperability with Windows or Samba.
- Optionally, the GID number for the group. All POSIX groups require a GID number, but IdM automatically assigns the GID number.Setting a GID number is not necessary because of the risk of collisions. If a GID number is given manually, IdM will not override the specified GID number, even if it is not unique.
- Click thebutton to go immediately to the member selection page.
- Select the members, as described in Section 9.11.2.2.1, “With the Web UI (Group Page)”.
9.11.2.1.2. With the Command Line
group-add
command. (This adds only the group; members are added separately.)
[bjensen@server ~]$ ipa group-add groupName --desc="description" [--nonposix]
--nonposix
. (By default, all groups are created as POSIX groups.) To enable interoperability with Windows users and groups and programs like Samba, it is possible to create non-POSIX groups by using the --nonposix
option. This option tells the script not to add the posixGroup
object class to the entry.
[bjensen@server ~]$ ipa group-add examplegroup --desc="for examples" --nonposix ---------------------- Added group "examplegroup" ---------------------- Group name: examplegroup Description: for examples GID: 855800010
[bjensen@server ~]$ ipa group-add Group name: engineering Description: for engineers ------------------------- Added group "engineering" ------------------------- Group name: engineering Description: for engineers GID: 387115842
Important
gidNumber
is unique. It will allow duplicate IDs; this is expected (though discouraged) behavior for POSIX entries.
ipa group-find --all
.
Note
9.11.2.2. Adding Group Members
9.11.2.2.1. With the Web UI (Group Page)
Note
- Open the Identity tab, and select the User Groups subtab.
- Click the name of the group to which to add members.
- Click the Add link at the top of the task area.
- Click the checkbox by the names of the users to add, and click the right arrows button,, to move the names to the selection box.
- Click thebutton.
9.11.2.2.2. With the Web UI (User's Page)
- Open the Identity tab, and select the Users subtab.
- Click the name of the user to edit.
- Open the User Groups tab on the user entry page.
- Click the Add link at the top of the task area.
- Click the checkbox by the names of the groups for the user to join, and click the right arrows button,, to move the groups to the selection box.
- Click thebutton.
9.11.2.2.3. With the Command Line
group-add-member
command. This command can add both users as group members and other groups as group members.
group-add-member
command requires only the group name and a comma-separated list of users to add:
[bjensen@server ~]$ ipa group-add-member groupName [--users=list] [--groups=list]
engineering
group:
[bjensen@server ~]$ ipa group-add-member engineering --users=jsmith,bjensen,mreynolds Group name: engineering Description: for engineers GID: 387115842 Member users: jsmith,bjensen,mreynolds ------------------------- Number of members added 3 -------------------------
[bjensen@server ~]$ ipa group-add-member engineering --groups=dev,qe1,dev2 Group name: engineering Description: for engineers GID: 387115842 Member groups: dev,qe1,dev2 ------------------------- Number of members added 3 -------------------------
[bjensen@server ~]$ ipa group-show examplegroup Group name: examplegroup Description: for examples GID: 93200002 Member users: jsmith,bjensen,mreynolds Member groups: californiausers Indirect Member users: sbeckett,acalavicci
Note
group-remove-member
command.
[bjensen@server ~]$ ipa group-remove-member engineering --users=jsmith Group name: engineering Description: for engineers GID: 855800009 Member users: bjensen,mreynolds --------------------------- Number of members removed 1 ---------------------------
9.11.2.2.4. Viewing Direct and Indirect Members of a Group
- Direct members, which are added explicitly to the group
- Indirect members, which are members of the group because they are members of another user group which is a member of the group
Figure 9.4. Indirect and Direct Members
9.11.2.3. Deleting User Groups
Warning
9.11.2.3.1. With the Web UI
- Open the Identity tab, and select the User Groups subtab.
- Select the checkbox by the name of the group to delete.
- Click the Delete link at the top of the task area.
- When prompted, confirm the delete action.
9.11.2.3.2. With the Command Line
group-del
command to deletes the specified group. For example:
[bjensen@server ~]$ ipa group-del examplegroup
9.11.3. Searching for Users and Groups
9.11.3.1. Setting Search Limits
9.11.3.1.1. Types of Search Limits and Where They Apply
- The search limit configuration for the IdM server. This is a setting for the IdM server itself, which is applied to all requests sent to the server from all IdM clients, the IdM CLI tools, and the IdM web UI for normal page display.By default, this limit is 100 entries.
- The time limit configuration for the IdM server. Much like the search size limit, the time limit sets a maximum amount of time that the IdM server, itself, waits for searches to run. Once it reaches that limit, the server stops the search and returns whatever entries were returned in that time.By default, this limit is two seconds.
- The page size limit. Although not strictly a search limit, the page size limit does limit how many entries are returned per page. The server returns the set of entries, up to the search limit, and then sorts and displays 20 entries per page. Paging results makes the results more understandable and more viewable.This is hard-coded to 20 for all searches.
- The LDAP search limit (--pkey option). All searches performed in the UI, and CLI searches which use the
--pkey
option, override the search limit set in the IdM server configuration and use the search limit set in the underlying LDAP directory.By default, this limit is 2000 entries. It can be edited by editing the 389 Directory Server configuration.
9.11.3.1.2. Setting IdM Search Limits
Important
9.11.3.1.2.1. With the Web UI
- Open the IPA Server tab.
- Select the Configuration subtab.
- Scroll to the Search Options area.
- Change the search limit settings.
- Search size limit, the maximum number of records to return in a search.
- Search time limit, the maximum amount of time, in seconds, to spend on a search before the server returns results.
Note
Setting the time limit or size limit value to -1 means that there are no limits on searches. - When the changes are complete, click the Update link at the top of the Configuration page.
9.11.3.1.2.2. With the Command Line
config-mod
command.
[bjensen@server ~]$ ipa config-mod --searchtimelimit=5 --searchrecordslimit=500 Max. username length: 32 Home directory base: /home Default shell: /bin/sh Default users group: ipausers Default e-mail domain for new users: example.com Search time limit: 5 Search size limit: 50 User search fields: uid,givenname,sn,telephonenumber,ou,title Group search fields: cn,description Enable migration mode: FALSE Certificate Subject base: O=EXAMPLE.COM Password Expiration Notification (days): 4
Note
9.11.3.1.3. Overriding the Search Defaults
*-find
command run through the command line.
--sizelimit
and --timelimit
options set alternative size and time limits, respectively, for that specific command run. The limits can be higher or lower, depending on the kinds of results you need.
[jsmith@ipaserver ~]$ ipa user-find smith --timelimit=120
9.11.3.2. Setting Search Attributes
9.11.3.2.1. Default Attributes Checked by Searches
User Search Attributes | |
First name | Last name |
Login ID | Job title |
Organizational unit | Phone number |
Group Search Attributes | |
Name | Description |
9.11.3.2.2. Changing User Search Attributes
9.11.3.2.2.1. From the Web UI
- Open the IPA Server tab.
- Select the Configuration subtab.
- Scroll to the User Options area.
- Add any additional search attributes, in a comma-separated list, in the User search fields field.
- When the changes are complete, click the Update link at the top of the Configuration page.
9.11.3.2.2.2. From the Command Line
--usersearch
option to set the attributes for user searches.
[bjensen@server ~]$ ipa config-mod --usersearch=uid,givenname,sn,telephonenumber,ou,title
Note
9.11.3.2.3. Changing Group Search Attributes
9.11.3.2.3.1. From the Web UI
- Open the IPA Server tab.
- Select the Configuration subtab.
- Scroll to the Group Options area.
- Add any additional search attributes, in a comma-separated list, in the Group search fields field.
- When the changes are complete, click the Update link at the top of the Configuration page.
9.11.3.2.3.2. From the Command Line
--groupsearch
options to set the attributes for group searches.
[bjensen@server ~]$ ipa config-mod --groupsearch=cn,description
Note
9.11.3.2.4. Limits on Attributes Returned in Search Results
9.11.3.3. Searching for Groups Based on Type
--private
option, however, limits the search results to only private groups.
[root@server ~]# ipa group-find --private --------------- 1 group matched --------------- Group name: jsmith Description: User private group for jsmith GID: 1084600001 ---------------------------- Number of entries returned 1 ----------------------------
jsmith
belongs to:
[root@server ~]# ipa group-find --user=jsmith --------------- 1 group matched --------------- Group name: ipausers Description: Default group for all users Member users: jsmith ---------------------------- Number of entries returned 1 ----------------------------
jsmith
does not belong to:
[root@server ~]# ipa group-find --no-user=jsmith ---------------- 3 groups matched ---------------- Group name: admins Description: Account administrators group GID: 1084600000 Member users: admin Group name: editors Description: Limited admins who can edit other users GID: 1084600002 Group name: trust admins Description: Trusts administrators group Member users: admin ---------------------------- Number of entries returned 3 ----------------------------
Option | Criteria Description |
---|---|
--private | Displays only private groups. |
--gid | Displays only the group which matches the complete, specified GID. |
--group-name | Displays only groups with that name or part of their name. |
--users, --no-users | Displays only groups which have the given users as members (or which do not include the given user). |
--in-hbacrules, --not-inhbac-rules | Displays only groups which belong to a given host-based access control rule (or which do not belong to the rule, for the --not-in option). There are similar options to display (or not) groups which belong to a specified sudo rule and role. |
--in-groups, --not-in-groups | Displays only groups which belong to another, specified group (or which do not belong to the group, for the --not-in option). There are similar options to display (or not) groups which belong to a specified netgroup. |
Chapter 10. Identity: Managing Hosts
- DNS entries and settings
- Machine authentication
- Hostname changes (which affect domain services)
10.1. About Hosts, Services, and Machine Identity and Authentication
- Service entries associated with the host
- The host and service principal
- Access control rules
- Machine information, such as its physical location and operating system
- DNS
- Kerberos
- Certificate management
- Joining the DNS domain (machine enrollment)
- Managing DNS entries and zones
- Managing machine authentication
- SSH keys. The SSH public key for the host is created and uploaded to the host entry. From there, the System Security Services Daemon (SSSD) uses IdM as an identity provider and can work in conjunction with OpenSSH and other services to reference the public keys located centrally in Identity Management. This is described in Section 10.4, “Managing Public SSH Keys for Hosts” and the Red Hat Enterprise Linux Deployment Guide.
- Key tables (or keytabs, a symmetric key resembling to some extent a user password) and machine certificates. Kerberos tickets are generated as part of the Kerberos services and policies defined by the server. Initially granting a Kerberos ticket, renewing the Kerberos credentials, and even destroying the Kerberos session are all handled by the IdM services. Managing Kerberos is covered in Chapter 20, Policy: Managing the Kerberos Domain.
- Machine certificates. In this case, the machine uses an SSL certificate that is issued by the IdM server's certificate authority and then stored in IdM's Directory Server. The certificate is then sent to the machine to present when it authenticates to the server. On the client, certificates are managed by a service called certmonger, which is described in Appendix B, Working with certmonger.
10.2. About Host Entry Configuration Properties
UI Field | Command-Line Option | Description |
---|---|---|
Description | --desc=description | A description of the host. |
Locality | --locality=locality | The geographic location of the host. |
Location | --location=location | The physical location of the host, such as its data center rack. |
Platform | --platform=string | The host hardware or architecture. |
Operating system | --os=string | The operating system and version for the host. |
MAC address | --macaddress=address | The MAC address for the host. This is a multi-valued attribute. The MAC address is used by the NIS plug-in to create a NIS ethers map for the host. |
SSH public keys | --sshpubkey=string | The full SSH public key for the host. This is a multi-valued attribute, so multiple keys can be set. |
Principal name (not editable) | --principalname=principal | The Kerberos principal name for the host. This defaults to the hostname during the client installation, unless a different principal is explicitly set in the -p . This can be changed using the command-line tools, but cannot be changed in the UI. |
Set One-Time Password | --password=string | Sets a password for the host which can be used in bulk enrollment. |
- | --random | Generates a random password to be used in bulk enrollment. |
- | --certificate=string | A certificate blob for the host. |
- | --updatedns | An attribute switch which sets whether the host can dynamically update its DNS entries if its IP address changes. |
10.3. Disabling and Re-enabling Host Entries
10.3.1. Disabling Host Entries
host-disable
command.
[jsmith@ipaserver ~]$ kinit admin [jsmith@ipaserver ~]$ ipa host-disable server.example.com
Important
10.3.2. Re-enabling Hosts
ipa-getkeytab
command. The -s
option sets which IdM server to request the keytab, -p
gives the principal name, and -k
gives the file to which to save the keytab.
[jsmith@ipaserver ~]$ ipa-getkeytab -s ipaserver.example.com -p host/server.example.com -k /etc/krb5.keytab -D fqdn=server.example.com,cn=computers,cn=accounts,dc=example,dc=com -w password
ipa-getkeytab
command is run on an active IdM client or server, then it can be run without any LDAP credentials (-D
and -w
). The IdM user uses Kerberos credentials to authenticate to the domain. To run the command directly on the disabled host, then supply LDAP credentials to authenticate to the IdM server. The credentials should correspond to the host or service which is being re-enabled.
10.4. Managing Public SSH Keys for Hosts
known_hosts
file. Any time that the remote machine attempts to access the target machine again, the target machine simply checks its known_hosts
file and then grants access automatically to approved hosts.
- The
known_hosts
file stores host entries in a triplet of the host IP address, hostname, and key. This file can rapidly become out of date if the IP address changes (which is common in virtual environments and data centers) or if the key is updated. - SSH keys have to be distributed manually and separately to all machines in an environment.
- Administrators have to approve host keys to add them to the configuration, but it is difficult to verify either the host or key issuer properly, which can create security problems.
10.4.1. About the SSH Key Format
~/.ssh/known_hosts
, a key entry is identified by the hostname and IP address of the server, its type, then lastly the key itself. For example:
host.example.com,1.2.3.4 ssh-rsa AAA...ZZZ==
"ssh-rsa ABCD1234...== ipaclient.example.com"
~/.ssh/known_hosts
file needs to be reordered to match the format of a user key, type key== comment:
ssh-rsa AAA...ZZZ== host.example.com,1.2.3.4
10.4.2. About ipa-client-install and OpenSSH
ipa-client-install
script, by default, configures an OpenSSH server and client on the IdM client machine. It also configures SSSD to perform host and user key caching. Essentially, simply configuring the client does all of the configuration necessary for the host to use SSSD, OpenSSH, and Identity Management for key caching and retrieval.
ssh
service is first started.
Note
ipa-client-install
, the client is created with two SSH keys, RSA and DSS.
--ssh-trust-dns
, which can be run with ipa-client-install
and automatically configures OpenSSH to trust the IdM DNS records, where the key fingerprints are stored.
--no-sshd
option. This prevents the install script from configuring the OpenSSH server.
--no-dns-sshfp
, prevents the host from creating DNS SSHFP records with its own DNS entries. This can be used with or without the --no-sshd
option.
10.4.3. Uploading Host SSH Keys Through the Web UI
- The key for a host can probably be retrieved from a
~/.ssh/known_hosts
. For example:server.example.com,1.2.3.4 ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEApvjBvSFSkTU0WQW4eOweeo0DZZ08F9Ud21xlLy6FOhzwpXFGIyxvXZ52+siHBHbbqGL5+14N7UvElruyslIHx9LYUR/pPKSMXCGyboLy5aTNl5OQ5EHwrhVnFDIKXkvp45945R7SKYCUtRumm0Iw6wq0XD4o+ILeVbV3wmcB1bXs36ZvC/M6riefn9PcJmh6vNCvIsbMY6S+FhkWUTTiOXJjUDYRLlwM273FfWhzHK+SSQXeBp/zIn1gFvJhSZMRi9HZpDoqxLbBB9QIdIw6U4MIjNmKsSI/ASpkFm2GuQ7ZK9KuMItY2AoCuIRmRAdF8iYNHBTXNfFurGogXwRDjQ==
If necessary, generate a host key. When using the OpenSSH tools, make sure to use a blank passphrase and to save the key to a different location than the user's~/.ssh/
directory, so it will not overwrite any existing keys.[jsmith@server ~]$ ssh-keygen -t rsa -C "server.example.com,1.2.3.4" Generating public/private rsa key pair. Enter file in which to save the key (/home/jsmith/.ssh/id_rsa): /home/jsmith/.ssh/host_keys Enter passphrase (empty for no passphrase): Enter same passphrase again: Your identification has been saved in /home/jsmith/.ssh/host_keys. Your public key has been saved in /home/jsmith/.ssh/host_keys.pub. The key fingerprint is: 4f:61:ee:2c:f7:d7:da:41:17:93:de:1d:19:ac:2e:c8 server.example.com The key's randomart image is: +--[ RSA 2048]----+ | .. | | .+| | o .* | | o . .. *| | S + . o+| | E . .. .| | . = . o | | o . ..o| | .....| +-----------------+
- Copy the public key from the key file. The full key entry has the form hostname,IP type key==. Only the key== is required, but the entire entry can be stored. To use all elements in the entry, rearrange the entry so it has the order type key== [hostname,IP]
[jsmith@server ~]$ cat /home/jsmith/.ssh/host_keys.pub ssh-rsa AAAAB3NzaC1yc2E...tJG1PK2Mq++wQ== server.example.com,1.2.3.4
- Open the Identity tab, and select the Hosts subtab.
- Click the name of the host to edit.
- In the Host Settings area of the Settings tab, click the SSH public keys: Add link.
- The UI opens a new link, New: key not set Show/Set key. Click the Show/Set key link.
- Paste in the public key for the host, and click thebutton.The SSH public keys field now shows New: key set. Clicking the Show/Set key link opens the submitted key.
- To upload multiple keys, click the Add link below the list of public keys, and upload the other keys.
- When all the keys have been submitted, click the Update link at the top of the host's page to save the changes.
Figure 10.1. Saved Public Key
10.4.4. Adding Host Keys from the Command Line
host-add
or by modifying the entry later.
Note
ipa-client-install
command, unless the SSH service is explicitly disabled in the installation script.
- Run the
host-mod
command with the--sshpubkey
option to upload the 64 bit-encoded public key to the host entry.Adding a host key also changes the DNS SSHFP entry for the host, so also use the--updatedns
option to update the host's DNS entry.For example:[jsmith@server ~]$ ipa host-mod --sshpubkey="ssh-rsa 12345abcde==" --updatedns host1.example.com
With a real key, the key is longer and usually ends with an equals sign (=).To upload multiple keys, pass a comma-separated list of keys with a single--sshpubkey
option:--sshpubkey="12345abcde==,key2==,key3=="
Note
A host can have multiple public keys. - After uploading the host keys, configure SSSD to use Identity Management as one of its identity domains and set up OpenSSH to use the SSSD tooling for managing host keys. This is covered in the Red Hat Enterprise Linux Deployment Guide.
10.4.5. Removing Host Keys
- Open the Identity tab, and select the Hosts subtab.
- Click the name of the host to edit.
- Open the Host Settings area of the Settings tab.
- Click the Delete link by the fingerprint of the key to remove.
- Click the Update link at the top of the host's page to save the changes.
ipa host-mod
with the --sshpubkey=
set to a blank value; this removes all public keys for the host. Also, use the --updatedns
option to update the host's DNS entry. For example:
[jsmith@server ~]$ kinit admin [jsmith@server ~]$ ipa host-mod --sshpubkey= --updatedns host1.example.com
10.5. Setting Ethers Information for a Host
ou=ethers
subtree.
cn=server,ou=ethers,dc=example,dc=com
- Add the MAC address attribute to a host entry. For example:
[jsmith@server ~]$ kinit admin [jsmith@server ~]$ ipa host-mod --macaddress=12:34:56:78:9A:BC server.example.com
- Open the
nsswitch.conf
file. - Add a line for the ethers service, and set it to use LDAP for its lookup.
ethers: ldap
- Check that the ethers information is available for the client.
[root@server ~]# getnt ethers server.example.com
10.6. Renaming Machines and Reconfiguring IdM Client Configuration
- Identify which services are running on the machine. These need to be re-created when the machine is re-enrolled.
# ipa service-find server.example.com
Each host has a default service which does not appear in the list of services. This service can be referred to as the "host service". The service principal for the host service ishost/<hostname>
, such ashost/server.example.com
. This principal can also be referred to as the host principal. - Identify all host groups to which the machine belongs.
[root@client ~]# kinit admin [root@client ~]# ipa hostgroup-find server.example.com
- Identify which of the services have certificates associated with them. This can be done using the
ldapsearch
command to check the entries in the IdM LDAP database directly:[root@client ~]# ldapsearch -x -b "cn=accounts,dc=example,dc=com" "(&(objectclass=ipaservice)(userCertificate=*))" krbPrincipalName -D "cn=directory manager" -w secret -h ipaserver.example.com -p 389
- For any service principals (in addition to the host principal), determine the location of the corresponding keytabs on
server.example.com
. The keytab location is different for each service, and IdM does not store this information.Each service on the client system has a Kerberos principal in the form service_name/hostname@REALM, such asldap/server.example.com@EXAMPLE.COM
. - Unenroll the client machine from the IdM domain:
[root@client ~]# ipa-client-install --uninstall
- For each identified keytab other than
/etc/krb5.keytab
, remove the old principals:[root@client ~]# ipa-rmkeytab -k /path/to/keytab -r EXAMPLE.COM
- On an IdM server, as an IdM administrator, remove the host entry. This removes all services and revokes all certificates issued for that host:
[root@server ~]# kinit admin [root@server ~]# ipa host-del server.example.com
At this point, the host is completely removed from IdM. - Rename the machine.
- Re-enroll the system with IdM:
[root@client ~]# ipa-client-install
This generates a host principal for with the new hostname in/etc/krb5.keytab
. - On an IdM server, add a new keytab for every service:
[root@server ~]# ipa service-add serviceName/new-hostname
- To generate certificates for services, use either
certmonger
or the IdM administration tools. - Re-add the host to any applicable host groups.
10.7. Managing Host Groups
10.7.1. Creating Host Groups
10.7.1.1. Creating Host Groups from the Web UI
- Open the Identity tab, and select the Host Groups subtab.
- Click the Add link at the top of the groups list.
- Enter the name and a description for the group.
- Click thebutton to go immediately to the member selection page.
- Select the members, as described in Section 10.7.2.2, “Adding Host Group Members from the Web UI”.
10.7.1.2. Creating Host Groups from the Command Line
hostgroup-add
command. (This adds only the group; members are added separately.)
$ ipa hostgroup-add groupName --desc="description"
10.7.2. Adding Host Group Members
10.7.2.1. Showing and Changing Group Members
10.7.2.2. Adding Host Group Members from the Web UI
- Open the Identity tab, and select the Host Groups subtab.
- Click the name of the group to which to add members.
- Click the Add link at the top of the task area.
- Click the checkbox by the names of the hosts to add, and click the right arrows button,, to move the hosts to the selection box.
- Click thebutton.
10.7.2.3. Adding Host Group Members from the Command Line
hostgroup-add-member
command. This command can add both hosts as group members and other groups as group members.
hostgroup-add-member
command requires only the group name and a comma-separated list of hosts to add:
$ ipa hostgroup-add-member groupName [--hosts=list] [--hostgroups=list]
caligroup
group:
$ ipa hostgroup-add-member caligroup --hosts=ipaserver.example.com,client1.example.com,client2.example.com Group name: caligroup Description: for machines in california GID: 387115842 Member hosts: ipaserver.example.com,client1.example.com,client2.example.com ------------------------- Number of members added 3 -------------------------
$ ipa hostgroup-add-member caligroup --groups=mountainview,sandiego Group name: caligroup Description: for machines in california GID: 387115842 Member groups: mountainview,sandiego ------------------------- Number of members added 2 -------------------------
Chapter 11. Identity: Managing Services
- DNS
- Kerberos
- Certificate management
11.1. Adding and Editing Service Entries and Keytabs
/etc/httpd/conf/ipa.keytab
.
Note
ipa.keytab
and that keytab file is deleted, the IdM web UI will stop working, because the original key would also be deleted.
ipa-getkeytab
, you should avoid using /etc/krb5.keytab
. This file should not contain service-specific keytabs; each service should have its keytab saved in a specific location and the access privileges (and possibly SELinux rules) should be configured so that only this service has access to the keytab.
11.1.1. Adding Services and Keytabs from the Web UI
- Open the Identity tab, and select the Services subtab.
- Click the Add link at the top of the services list.
- Select the service type from the drop-down menu, and give it a name.
- Select the hostname of the IdM host on which the service is running. The hostname is used to construct the full service principal name.
- Click the Add button to save the new service principal.
- Use the
ipa-getkeytab
command to generate and assign the new keytab for the service principal.[root@ipaserver ~]# # ipa-getkeytab -s ipaserver.example.com -p HTTP/server.example.com -k /etc/httpd/conf/krb5.keytab -e aes256-cts
- The realm name is optional. The IdM server automatically appends the Kerberos realm for which it is configured. You cannot specify a different realm.
- The hostname must resolve to a DNS A record for it to work with Kerberos. You can use the
--force
flag to force the creation of a principal should this prove necessary. - The
-e
argument can include a comma-separated list of encryption types to include in the keytab. This supersedes any default encryption type.
Warning
Creating a new key resets the secret for the specified principal. This means that all other keytabs for that principal are rendered invalid.
11.1.2. Adding Services and Keytabs from the Command Line
- Create the service principal. The service is recognized through a name like service/FQDN:
# ipa service-add serviceName/hostname
For example:$ ipa service-add HTTP/server.example.com ------------------------------------------------------- Added service "HTTP/server.example.com@EXAMPLE.COM" ------------------------------------------------------- Principal: HTTP/server.example.com@EXAMPLE.COM Managed by: ipaserver.example.com
- Create the service keytab file using the
ipa-getkeytab
command. This command is run on the client in the IdM domain. (Actually, it can be run on any IdM server or client, and then the keys copied to the appropriate machine. However, it is simplest to run the command on the machine with the service being created.)The command requires the Kerberos service principal (-p
), the IdM server name (-s
), the file to write (-k
), and the encryption method (-e
). Be sure to copy the keytab to the appropriate directory for the service.For example:# ipa-getkeytab -s server.example.com -p HTTP/server.example.com -k /etc/httpd/conf/krb5.keytab -e aes256-cts
- The realm name is optional. The IdM server automatically appends the Kerberos realm for which it is configured. You cannot specify a different realm.
- The hostname must resolve to a DNS A record for it to work with Kerberos. You can use the
--force
flag to force the creation of a principal should this prove necessary. - The
-e
argument can include a comma-separated list of encryption types to include in the keytab. This supersedes any default encryption type.
Warning
Theipa-getkeytab
command resets the secret for the specified principal. This means that all other keytabs for that principal are rendered invalid.
11.2. Adding Services and Certificates for Services
11.2.1. Adding Services and Certificates from the Web UI
- Open the Identity tab, and select the Services subtab.
- Click the Add link at the top of the services list.
- Select the service type from the drop-down menu, and give it a name.
- Select the hostname of the IdM host on which the service is running. The hostname is used to construct the full service principal name.
- Click the Add and Edit button to go directly to the service entry page.
- Scroll to the bottom of the page, to the Service Certificate section.
- Click the New Certificate button to create the service certificate.
11.2.2. Adding Services and Certificates from the Command Line
- Create the service principal. The service is recognized through a name like service/FQDN:
[jsmith@ipaserver ~]$ kinit admin [jsmith@ipaserver ~]$ ipa service-add serviceName/hostname
For example:$ ipa service-add HTTP/server.example.com ------------------------------------------------------- Added service "HTTP/server.example.com@EXAMPLE.COM" ------------------------------------------------------- Principal: HTTP/server.example.com@EXAMPLE.COM Managed by: ipaserver.example.com
- Create a certificate for the service. Be sure to copy the keytab to the appropriate directory for the service.For example:
$ ipa cert-request --principal=HTTP/web.example.com example.csr
Note
Use the--add
option to create the service automatically when requesting the certificate.Alternatively, use thegetcert
command, which creates and manages the certificate throughcertmonger
. The options are described more in Section B.1, “Requesting a Certificate with certmonger”.$ ipa-getcert request -d /etc/httpd/alias -n Server-Cert -K HTTP/client1.example.com -N 'CN=client1.example.com,O=EXAMPLE.COM'
11.3. Storing Certificates in NSS Databases
- Create the NSS databases.
$ certutil -N -d /path/to/database/dir
- Request the certificate using
certutil
, an NSS tool.$ certutil -R -s "CN=client1.example.com,O=EXAMPLE.COM" -d /path/to/database/dir -a > example.csr
11.4. Configuring Clustered Services
- Enroll all of the hosts in the cluster into the IdM domain.
- Create any service principals and generate the required keytabs.
- Collect any keytabs that have been set up for services on the host, including the host keytab at
/etc/krb5.keytab
. - Use the
ktutil
command to produce a single keytab file that contains the contents of all of the keytab files.- For each file, use the
rkt
command to read the keys from that file. - Use the
wkt
command to write all of the keys which have been read to a new keytab file.
- Replace the keytab files on each host with the newly-created combined keytab file.
- At this point, each host in this cluster can now impersonate any other host.
- Some services require additional configuration to accommodate cluster members which do not reset hostnames when taking over a failed service.
- For
sshd
, setGSSAPIStrictAcceptorCheck no
in/etc/ssh/sshd_config
. - For
mod_auth_kerb
, setKrbServiceName Any
in/etc/httpd/conf.d/auth_kerb.conf
.
Note
11.5. Using the Same Service Principal for Multiple Services
- Retrieve a service principal using the
ipa-getkeytab
command.# ipa-getkeytab -s kdc.example.com -p HTTP/server.example.com -k /etc/httpd/conf/krb5.keytab -e aes256-cts
- Either direct multiple servers or services to use the same file, or copy the file to individual servers as required.
11.6. Disabling and Re-enabling Service Entries
11.6.1. Disabling Service Entries
service-disable
command.
[jsmith@ipaserver ~]$ kinit admin $ ipa service-disable http/server.example.com
Important
11.6.2. Re-enabling and Services
ipa-getkeytab
command. The -s
option sets which IdM server to request the keytab, -p
gives the principal name, and -k
gives the file to which to save the keytab.
[root@ipaserver ~]# ipa-getkeytab -s ipaserver.example.com -p HTTP/server.example.com -k /etc/httpd/conf/krb5.keytab -e aes256-cts
ipa-getkeytab
command is run on an active IdM client or server, then it can be run without any LDAP credentials (-D
and -w
). The IdM user uses Kerberos credentials to authenticate to the domain. To run the command directly on a disabled host, then supply LDAP credentials to authenticate to the IdM server. The credentials should correspond to the host or service which is being re-enabled.
Chapter 12. Identity: Delegating Access to Hosts and Services
managedby
entry which lists what hosts or services can manage it. By default, a host can manage itself and all of its services. It is also possible to allow a host to manage other hosts, or services on other hosts, by updating the appropriate delegations or providing a suitable managedby
entry.
Figure 12.1. Host and Service Delegation
Note
managedBy
entry, it does not mean that the host has also been delegated management for all services on that host. Each delegation has to be performed independently.
12.1. Delegating Service Management
service-add-host
command. There are two parts to delegating the service: specifying the principal and identifying the hosts (in a comma-separated list) with control:
# ipa service-add-host principal --hosts=hostnames
# ipa service-add-host http/web.example.com --hosts=client1.example.com
# kinit -kt /etc/krb5.keytab host/`hostname` # ipa-getkeytab -s `hostname` -k /tmp/test.keytab -p http/web.example.com Keytab successfully retrieved and stored in: /tmp/test.keytab
cert-request
command to create a service entry and load the certification information:
# ipa cert-request --add --principal=http/web.example.com web.csr Certificate: MIICETCCAXqgA...[snip] Subject: CN=web.example.com,O=EXAMPLE.COM Issuer: CN=EXAMPLE.COM Certificate Authority Not Before: Tue Feb 08 18:51:51 2011 UTC Not After: Mon Feb 08 18:51:51 2016 UTC Fingerprint (MD5): c1:46:8b:29:51:a6:4c:11:cd:81:cb:9d:7c:5e:84:d5 Fingerprint (SHA1): 01:43:bc:fa:b9:d8:30:35:ee:b6:54:dd:a4:e7:d2:11:b1:9d:bc:38 Serial number: 1005
12.2. Delegating Host Management
host-add-managedby
command. This creates a managedby
entry. Once the managedby
entry is created, then the host can retrieve a keytab for the host it has delegated authority over.
- Log in as the admin user.
# kinit admin
- Add the
managedby
entry. For example, this delegates authority over client2 to client1.# ipa host-add-managedby client2.example.com --hosts=client1.example.com
- Obtain a ticket as the host
client1
and then retrieve a keytab forclient2
:# kinit -kt /etc/krb5.keytab host/`hostname` # ipa-getkeytab -s `hostname` -k /tmp/client2.keytab -p host/client2.example.com Keytab successfully retrieved and stored in: /tmp/client2.keytab
12.3. Delegating Host or Service Management in the Web UI
- Open the Identity tab, and select the Hosts or Services subtab.
- Click the name of the host or service that you are going to grant delegated management to.
- Click the Hosts subtab on the far right of the host/service entry. This is the tab which lists hosts which can manage the selected host/service.
- Click the Add link at the top of the list.
- Click the checkbox by the names of the hosts to which to delegate management for the host/service. Click the right arrows button,, to move the hosts to the selection box.
- Click thebutton to close the selection box and to save the delegation settings.
12.4. Accessing Delegated Services
host
.
kinit
, use the -k
option to load a keytab and the -t
option to specify the keytab.
# kinit -kt /etc/krb5.keytab host/ipa.example.com@EXAMPLE.COM
# kinit -kt /etc/httpd/conf/krb5.keytab http/ipa.example.com@EXAMPLE.COM
Chapter 13. Identity: Integrating with NIS Domains and Netgroups
13.1. About NIS and Identity Management
nss_ldap
or SSSD fetches the object using an encrypted LDAP connection.
host,user,domainA netgroup triple associates the user or the host with the domain; it does not associate the user and the host with each other. Therefore, a triple usually defines a host or a user for better clarity and management.
host.example.com,,nisdomain.example.com -,jsmith,nisdomain.example.com
memberUser
parameter. Likewise, hosts can be either a single host or a host group; both are identified by the memberHost
attribute.
dn: ipaUniqueID=d4453480-cc53-11dd-ad8b-0800200c9a66,cn=ng,cn=accounts,... objectclass: top objectclass: ipaAssociation objectclass: ipaNISNetgroup ipaUniqueID: d4453480-cc53-11dd-ad8b-0800200c9a66 cn: netgroup1 memberHost: fqdn=host1.example.com,cn=computers,cn=accounts,... memberHost: cn=VirtGuests,cn=hostgroups,cn=accounts,... memberUser: cn=jsmith,cn=users,cn=accounts,... memberUser: cn=bjensen,cn=users,cn=accounts,... memberUser: cn=Engineering,cn=groups,cn=accounts,... nisDomainName: nisdomain.example.com
netgroup-*
commands, which show the basic LDAP entry:
# ipa netgroup-show netgroup1 Netgroup name: netgroup1 Description: my netgroup NIS domain name: nisdomain Member User: jsmith Member User: bjensen Member User: Engineering Member Host: host1.example.com Member Host: VirtGuests
13.2. Setting the NIS Port for Identity Management
Note
- Enable the NIS listener and compatibility plug-ins:
[root@ipaserver ~]# ipa-nis-manage enable [root@ipaserver ~]# ipa-compat-manage enable
- Edit the plug-in configuration and add the port number as an argument. For example, to set the port to 514:
[root@ipaserver ~]# ldapmodify -x -D 'cn=directory manager' -w secret dn: cn=NIS Server,cn=plugins,cn=config changetype: modify add: nsslapd-pluginarg0 nsslapd-pluginarg0: 514 modifying entry "cn=NIS Server,cn=plugins,cn=config"
- Restart the Directory Server to load the new plug-in configuration.
[root@ipaserver ~]# service dirsrv restart
13.3. Creating Netgroups
13.3.1. Adding Netgroups
13.3.1.1. With the Web UI
- Open the Identity tab, and select the Netgroups subtab.
- Click the Add link at the top of the netgroups list.
- Enter both a unique name and a description for the netgroup. Both the name and description are required.The group name is the identifier used for the netgroup in the IdM domain, and it cannot be changed after it is created. The name cannot contain spaces, but other separators like an underscore (_) are allowed.
- Click thebutton to go immediately to the netgroup's edit pages.
- Optionally, set the NIS domain for the netgroup. This defaults to the IdM domain, but it can be changed.
- Click the Settings tab.
- Enter the name of the alternate NIS domain in the NIS domain name field.The NIS domain name field sets the domain that appears in the netgroup triple. It does not affect which NIS domain the Identity Management listener responds to.
- Add members, as described in Section 13.3.2.1, “With the Web UI”.
13.3.1.2. With the Command Line
netgroup-add
command. This adds only the group; members are added separately. Two attributes are always required: the group name and the group description. If those attributes are not given as arguments, then the script prompts for them. There is also an option to set the NIS domain name to use for the group; this defaults to the IdM domain, but it can be set to something different, depending on the network configuration.
$ ipa netgroup-add --desc="description" [--nisdomain=domainName] groupName
# ipa netgroup-add --desc="my new netgroup" example-netgroup # ipa netgroup-add-member --hosts=ipa.example.com example-netgroup # ypcat -d example.com -h ipa.example.com netgroup (ipa.example.com,-,example.com)
Note
--nisdomain
option sets the domain that appears in the netgroup triple. It does not affect which NIS domain the Identity Management listener responds to.
13.3.2. Adding Netgroup Members
Note
13.3.2.1. With the Web UI
- Open the Identity tab, and select the Netgroups subtab.
- Click the name of the netgroup to which to add members.
- Select the tab for the type of netgroup member to add. Netgroups can have users, user groups, hosts, host groups, and other netgroups as members.
- Click the Add link at the top of the task area.
- Click the checkbox by the names of the users to add, and click the right arrows button,, to move the names to the selection box.
- Click thebutton.
13.3.2.2. With the Command Line
netgroup-add-member
command. Users, groups, hosts, host groups, and other netgroups can all be added to the netgroup entry. The entry name of the NIS group being edited usually comes at the end of the command:
# ipa netgroup-add-member --users=users --groups=groups --hosts=hosts --hostgroups=hostGroups --netgroups=netgroups groupName
# ipa netgroup-add-member --users=jsmith,bjensen --groups=ITadmin --hosts=host1.example.com,host2.example.com --hostgroups=EngDev --netgroups=nisgroup2 example-group
13.4. Exposing Automount Maps to NIS Clients
cn=automount
branch of the IdM directory tree.
ldapadd
, and editing the directory directly. For example, this adds an automount map that is named auto.example
in a location named default
and for a server named nisserver
:
[root@server ~]# ldapadd -h nisserver.example.com -x -D "cn=Directory Manager" -w secret dn: nis-domain=example.com+nis-map=auto.example,cn=NIS Server,cn=plugins,cn=config objectClass: extensibleObject nis-domain: example.com nis-map: auto.example nis-filter: (objectclass=automount) nis-key-format: %{automountKey} nis-value-format: %{automountInformation} nis-base: automountmapname=auto.example,cn=default,cn=automount,dc=example,dc=com
13.5. Migrating from NIS to IdM
13.5.1. Preparing Netgroup Entries in IdM
Determine what applications are using the user information in the NIS server. While some clients (like sudo
) require NIS netgroups, many clients can use Unix groups instead. If no netgroups are required, then simply create corresponding user accounts in IdM and delete the netgroups entirely. Otherwise, create the user entries in IdM and then create an IdM-managed netgroup and add those users as members. This is described in Section 13.3, “Creating Netgroups”.
Whenever a host group is created in IdM, a corresponding shadow NIS group is automatically created. These netgroups can then be managed using the ipa-host-net-manage
command.
It may be necessary to have an exact conversion, with every NIS user and host having an exact corresponding entry in IdM. In that case, each entry can be created using the original NIS names:
- Create an entry for every user referenced in a netgroup.
- Create an entry for every host referenced in a netgroup.
- Create a netgroup with the same name as the original netgroup.
- Add the users and hosts as direct members of the netgroup. Alternatively, add the users and hosts into IdM groups or other netgroups, and then add those groups as members to the netgroup.
13.5.2. Enabling the NIS Listener in Identity Management
slapi-nis
plug-in sets up a special NIS listener that receives incoming NIS requests and manages the NIS maps within the Directory Server. Identity Management uses three NIS maps:
- passwd
- group
- netgroup
slapi-nis
plug-in is not enabled by default. To enable NIS for Identity Management:
- Obtain new Kerberos credentials as an IdM admin user.
[root@ipaserver ~]# kinit admin
- Enable the NIS listener and compatibility plug-ins:
[root@ipaserver ~]# ipa-nis-manage enable [root@ipaserver ~]# ipa-compat-manage enable
- Restart the DNS and Directory Server service:
[root@server ~]# service rpcbind restart [root@server ~]# service dirsrv restart
13.5.3. Exporting and Importing the Existing NIS Data
ypcat
and then looping through that output and creating the IdM entries with the corresponding ipa *-add
commands. While this could be done manually, it is easiest to script it. These examples use a shell script.
13.5.3.1. Importing User Entries
/etc/passwd
file contains all of the NIS user information. These entries can be used to create IdM user accounts with UID, GID, gecos, shell, home directory, and name attributes that mirror the NIS entries.
nis-user.sh
:
#!/bin/sh # 1 is the nis domain, 2 is the nis master server ypcat -d $1 -h $2 passwd > /dev/shm/nis-map.passwd 2>&1 IFS=$'\n' for line in $(cat /dev/shm/nis-map.passwd); do IFS=' ' username=$(echo $line|cut -f1 -d:) # Not collecting encrypted password because we need cleartext password to create kerberos key uid=$(echo $line|cut -f3 -d:) gid=$(echo $line|cut -f4 -d:) gecos=$(echo $line|cut -f5 -d:) homedir=$(echo $line|cut -f6 -d:) shell=$(echo $line|cut -f7 -d:) # Now create this entry echo passw0rd1|ipa user-add $username --first=NIS --last=USER --password --gidnumber=$gid --uid=$uid --gecos=$gecos --homedir=$homedir --shell=$shell ipa user-show $username done
[root@nis-server ~]# kinit admin [root@nis-server ~]# ./nis-user.sh nisdomain nis-master.example.com
Note
13.5.3.2. Importing Group Entries
/etc/group
file contains all of the NIS group information. These entries can be used to create IdM user group accounts with the GID, gecos, shell, home directory, and name attributes that mirror the NIS entries.
nis-group.sh
:
#!/bin/sh # 1 is the nis domain, 2 is the nis master server ypcat -d $1 -h $2 group > /dev/shm/nis-map.group 2>&1 IFS=$'\n' for line in $(cat /dev/shm/nis-map.group); do IFS=' ' groupname=$(echo $line|cut -f1 -d:) # Not collecting encrypted password because we need cleartext password to create kerberos key gid=$(echo $line|cut -f3 -d:) members=$(echo $line|cut -f4 -d:) # Now create this entry ipa group-add $groupname --desc=NIS_GROUP_$groupname --gid=$gid if [ -n "$members" ]; then ipa group-add-member $groupname --users=$members fi ipa group-show $groupname done
[root@nis-server ~]# kinit admin [root@nis-server ~]# ./nis-group.sh nisdomain nis-master.example.com
13.5.3.3. Importing Host Entries
/etc/hosts
file contains all of the NIS host information. These entries can be used to create IdM host accounts that mirror the NIS entries.
nis-hosts.sh
:
#!/bin/sh # 1 is the nis domain, 2 is the nis master server ypcat -d $1 -h $2 hosts | egrep -v "localhost|127.0.0.1" > /dev/shm/nis-map.hosts 2>&1 IFS=$'\n' for line in $(cat /dev/shm/nis-map.hosts); do IFS=' ' ipaddress=$(echo $line|awk '{print $1}') hostname=$(echo $line|awk '{print $2}') master=$(ipa env xmlrpc_uri |tr -d '[:space:]'|cut -f3 -d:|cut -f3 -d/) domain=$(ipa env domain|tr -d '[:space:]'|cut -f2 -d:) if [ $(echo $hostname|grep "\." |wc -l) -eq 0 ]; then hostname=$(echo $hostname.$domain) fi zone=$(echo $hostname|cut -f2- -d.) if [ $(ipa dnszone-show $zone 2>/dev/null | wc -l) -eq 0 ]; then ipa dnszone-add --name-server=$master --admin-email=root.$master fi ptrzone=$(echo $ipaddress|awk -F. '{print $3 "." $2 "." $1 ".in-addr.arpa."}') if [ $(ipa dnszone-show $ptrzone 2>/dev/null|wc -l) -eq 0 ]; then ipa dnszone-add $ptrzone --name-server=$master --admin-email=root.$master fi # Now create this entry ipa host-add $hostname --ip-address=$ipaddress ipa host-show $hostname done
[root@nis-server ~]# kinit admin [root@nis-server ~]# ./nis-hosts.sh nisdomain nis-master.example.com
Note
13.5.3.4. Importing Netgroup Entries
/etc/netgroup
file contains all of the NIS netgroup information. These entries can be used to create IdM netgroup accounts that mirror the NIS entries.
nis-netgroup.sh
:
#!/bin/sh # 1 is the nis domain, 2 is the nis master server ypcat -k -d $1 -h $2 netgroup > /dev/shm/nis-map.netgroup 2>&1 IFS=$'\n' for line in $(cat /dev/shm/nis-map.netgroup); do IFS=' ' netgroupname=$(echo $line|awk '{print $1}') triples=$(echo $line|sed "s/^$netgroupname //") echo "ipa netgroup-add $netgroupname --desc=NIS_NG_$netgroupname" if [ $(echo $line|grep "(,"|wc -l) -gt 0 ]; then echo "ipa netgroup-mod $netgroupname --hostcat=all" fi if [ $(echo $line|grep ",,"|wc -l) -gt 0 ]; then echo "ipa netgroup-mod $netgroupname --usercat=all" fi for triple in $triples; do triple=$(echo $triple|sed -e 's/-//g' -e 's/(//' -e 's/)//') if [ $(echo $triple|grep ",.*,"|wc -l) -gt 0 ]; then hostname=$(echo $triple|cut -f1 -d,) username=$(echo $triple|cut -f2 -d,) domain=$(echo $triple|cut -f3 -d,) hosts=""; users=""; doms=""; [ -n "$hostname" ] && hosts="--hosts=$hostname" [ -n "$username" ] && users="--users=$username" [ -n "$domain" ] && doms="--nisdomain=$domain" echo "ipa netgroup-add-member $hosts $users $doms" else netgroup=$triple echo "ipa netgroup-add $netgroup --desc=NIS_NG_$netgroup" fi done done
ipa netgroup-add-member
command always adds a host, user, and domain triple to the netgroup.
if [ $(echo $triple|grep ",.*,"|wc -l) -gt 0 ]; then hostname=$(echo $triple|cut -f1 -d,) username=$(echo $triple|cut -f2 -d,) domain=$(echo $triple|cut -f3 -d,) hosts=""; users=""; doms=""; [ -n "$hostname" ] && hosts="--hosts=$hostname" [ -n "$username" ] && users="--users=$username" [ -n "$domain" ] && doms="--nisdomain=$domain" echo "ipa netgroup-add-member $hosts $users $doms"
server,,domain
the options with the member add command are --hosts=server --users="" --nisdomain=domain
.
[root@nis-server ~]# kinit admin [root@nis-server ~]# ./nis-hosts.sh nisdomain nis-master.example.com
13.5.3.5. Importing Automount Maps
#!/bin/sh # 1 is for the automount entry in ipa ipa automountlocation-add $1 # 2 is the nis domain, 3 is the nis master server, 4 is the map name ypcat -k -d $2 -h $3 $4 > /dev/shm/nis-map.$4 2>&1 ipa automountmap-add $1 $4 basedn=$(ipa env basedn|tr -d '[:space:]'|cut -f2 -d:) cat > /tmp/amap.ldif <<EOF dn: nis-domain=nisdomain.example.com+nis-map=$4,cn=NIS Server,cn=plugins,cn=config objectClass: extensibleObject nis-domain: $3 nis-map: $4 nis-base: automountmapname=$4,cn=nis,cn=automount,$basedn nis-filter: (objectclass=*) nis-key-format: %{automountKey} nis-value-format: %{automountInformation} EOF ldapadd -x -h $3 -D "cn=directory manager" -w secret -f /tmp/amap.ldif IFS=$'\n' for line in $(cat /dev/shm/nis-map.$4); do IFS=" " key=$(echo "$line" | awk '{print $1}') info=$(echo "$line" | sed -e "s#^$key[ \t]*##") ipa automountkey-add nis $4 --key="$key" --info="$info" done
[root@nis-server ~]# kinit admin [root@nis-server ~]# ./nis-hosts.sh location nisdomain nis-master.example.com map
13.5.4. Setting Weak Password Encryption for NIS User Authentication to IdM
kinit
fails with password failures.
passwordStorageScheme
attribute using ldapmodify
:
[root@server ~]# ldapmodify -D "cn=directory server" -w secret -p 389 -h ipaserver.example.com dn: cn=config changetype: modify replace: passwordStorageScheme passwordStorageScheme: crypt
Note
Chapter 14. Identity: Integrating with Active Directory Through Cross-forest Trust (Technology Preview)
Note
Cross-forest Trust As Technology Preview in Red Hat Enterprise Linux 6
Overview of Cross-forest Trust in Red Hat Enterprise Linux 6
- Establish a trust to a single AD forest.
- Allow access to IdM resources for users from the root domain of a trusted AD forest.
- Override default attributes of AD users, such as the login shell or home directory, in a centralized way. To achieve this, deploy ID views using IdM in Red Hat Enterprise Linux 7.
- Expose AD users and groups using the compatibility tree for legacy clients. To provide legacy clients with access to AD users and groups, use IdM in Red Hat Enterprise Linux 7.
Trusts vs Synchronization
Chapter 15. Identity: Integrating with Microsoft Active Directory Through Synchronization
15.1. Supported Windows Platforms
- Windows Server 2008 R2
- Windows Server 2012 R2
15.2. About Active Directory and Identity Management
- A synchronization operation runs every five minutes.
- Synchronization can only be configured with one Active Directory domain. Multiple domains are not supported.
- Synchronization can only be configured with one Active Directory domain controller.
- Only user information is synchronized.
- Both user attributes and passwords can be synchronized.
- While modifications are bi-directional (going both from Active Directory to IdM and from IdM to Active Directory), creating or adding accounts are only uni-directional, from Active Directory to Identity Management. New accounts created in Active Directory are synchronized over to IdM automatically. However, user accounts created in IdM must also be created in Active Directory before they will be synchronized.
- Account lock information is synchronized by default, so a user account which is disabled in one domain is disabled in the other.
- Password synchronization changes take effect immediately.
15.3. About Synchronized Attributes
Note
User Schema That Are the Same in Identity Management and Windows Servers
- cn[5]
- physicalDeliveryOfficeName
- description
- postOfficeBox
- destinationIndicator
- postalAddress
- facsimileTelephoneNumber
- postalCode
- givenname
- registeredAddress
- homePhone
- sn
- homePostalAddress
- st
- initials
- street
- l
- telephoneNumber
- mail
- teletexTerminalIdentifier
- mobile
- telexNumber
- o
- title
- ou
- usercertificate
- pager
- x121Address
Identity Management | Active Directory |
---|---|
cn[a] | name |
nsAccountLock | userAccountControl |
ntUserDomainId | sAMAccountName |
ntUserHomeDir | homeDirectory |
ntUserScriptPath | scriptPath |
ntUserLastLogon | lastLogon |
ntUserLastLogoff | lastLogoff |
ntUserAcctExpires | accountExpires |
ntUserCodePage | codePage |
ntUserLogonHours | logonHours |
ntUserMaxStorage | maxStorage |
ntUserProfile | profilePath |
ntUserParms | userParameters |
ntUserWorkstations | userWorkstations |
[a]
The cn is mapped directly (cn to cn ) when syncing from Identity Management to Active Directory. When syncing from Active Directory cn is mapped from the name attribute in Active Directory to the cn attribute in Identity Management.
|
15.3.1. User Schema Differences between Identity Management and Active Directory
15.3.1.1. Values for cn Attributes
cn
attribute can be multi-valued, while in Active Directory this attribute must have only a single value. When the Identity Management cn
attribute is synchronized, then, only one value is sent to the Active Directory peer.
cn
value is added to an Active Directory entry and that value is not one of the values for cn
in Identity Management, then all of the Identity Management cn
values are overwritten with the single Active Directory value.
cn
attribute as its naming attribute, where Identity Management uses uid
. This means that there is the potential to rename the entry entirely (and accidentally) if the cn
attribute is edited in the Identity Management. If that cn
change is written over to the Active Directory entry, then the entry is renamed, and the new named entry is written back over to Identity Management.
15.3.1.2. Values for street and streetAddress
streetAddress
for a user's postal address; this is the way that 389 Directory Server uses the street
attribute. There are two important differences in the way that Active Directory and Identity Management use the streetAddress
and street
attributes, respectively:
- In 389 Directory Server,
streetAddress
is an alias forstreet
. Active Directory also has thestreet
attribute, but it is a separate attribute that can hold an independent value, not an alias forstreetAddress
. - Active Directory defines both
streetAddress
andstreet
as single-valued attributes, while 389 Directory Server definesstreet
as a multi-valued attribute, as specified in RFC 4519.
streetAddress
and street
attributes, there are two rules to follow when setting address attributes in Active Directory and Identity Management:
- The synchronization process maps
streetAddress
in the Active Directory entry tostreet
in Identity Management. To avoid conflicts, thestreet
attribute should not be used in Active Directory. - Only one Identity Management
street
attribute value is synced to Active Directory. If thestreetAddress
attribute is changed in Active Directory and the new value does not already exist in Identity Management, then allstreet
attribute values in Identity Management are replaced with the new, single Active Directory value.
15.3.1.3. Constraints on the initials Attribute
initials
attribute, Active Directory imposes a maximum length constraint of six characters, but 389 Directory Server does not have a length limit. If an initials
attribute longer than six characters is added to Identity Management, the value is trimmed when it is synchronized with the Active Directory entry.
15.3.1.4. Requiring the surname (sn) Attribute
person
entries to be created without a surname attribute. However, RFC 4519 defines the person
object class as requiring a surname attribute, and this is the definition used in Directory Server.
person
entry is created without a surname attribute, that entry will not be synced over to IdM since it fails with an object class violation.
15.3.2. Active Directory Entries and RFC 2307 Attributes
uidNumber
and gidNumber
attributes. This allows Windows user entries to follow the specifications for those attributes in RFC 2307.
uidNumber
and gidNumber
attributes are not actually used as the uidNumber
and gidNumber
attributes for the Identity Management entry. The Identity Management uidNumber
and gidNumber
attributes are generated when the Windows user is synced over.
Note
uidNumber
and gidNumber
attributes defined and used in Identity Management are not the same uidNumber
and gidNumber
attributes defined and used in the Active Directory entry, and the numbers are not related.
15.4. Setting up Active Directory for Synchronization
15.4.1. Creating an Active Directory User for Sync
- Grant the sync user account Replicating directory changes rights to the synchronized Active Directory subtree. Replicator rights are required for the sync user to perform synchronization operations.Replicator rights are described in http://support.microsoft.com/kb/303972.
- Add the sync user as a member of the Account Operator and Enterprise Read-Only Domain controller groups. It is not necessary for the user to belong to the full Domain Admin group.
15.4.2. Setting up an Active Directory Certificate Authority
15.5. Managing Synchronization Agreements
15.5.1. Trusting the Active Directory and IdM CA Certificates
- On the Active Directory server, download the IdM server's CA certificate from
http://ipa.example.com/ipa/config/ca.crt
. - Install the IdM CA certificate in the Active Directory certificate database. This can be done using the Microsoft Management Console or the certutil utility. For example:
certutil -installcert -v -config "ipaserver.example.com\Example Domain CA" c:\path\to\ca.crt
For more details, see the Active Directory documentation. - Export the Active Directory CA certificate.
- In My Network Places, open the CA distribution point.
- Double-click the security certificate file (
.crt
file) to display the Certificate dialog box. - On the Details tab, click to start the Certificate Export Wizard.
- Click Base-64 encoded X.509 (.CER)., and then select
- Specify a suitable directory and file name for the exported file. Clickto export the certificate, and then click .
- Copy the Active Directory certificate over to the IdM server machine.
- Download the IdM server's CA certificate from
http://ipa.example.com/ipa/config/ca.crt
. - Copy both the Active Directory CA certificate and the IdM CA certificate into the
/etc/openldap/cacerts/
directory. - Update the hash symlinks for the certificates.
cacertdir_rehash /etc/openldap/cacerts/
- Edit the
/etc/openldap/ldap.conf
file, and add the information to point to and use the certificates in the/etc/openldap/cacerts/
directory.TLS_CACERTDIR /etc/openldap/cacerts/ TLS_REQCERT allow
15.5.2. Creating Synchronization Agreements
ipa-replica-manage connect
command because it creates a connection to the Active Directory domain. The options to create the synchronization agreement are listed in Table 15.2, “Synchronization Agreement Options”.
- Make sure that the Active Directory and IdM servers trust each other's CA certificates, as in Section 15.5.1, “Trusting the Active Directory and IdM CA Certificates”.
- Remove any existing Kerberos credentials on the IdM server.
$ kdestroy
- Use the
ipa-replica-manage
command to create a Windows synchronization agreement. This requires the--winsync
option. If passwords will be synchronized as well as user accounts, then also use the--passsync
option and set a password to use for Password Sync.The--binddn
and--bindpwd
options give the username and password of the system account on the Active Directory server that IdM will use to connect to the Active Directory server.$ ipa-replica-manage connect --winsync --binddn cn=administrator,cn=users,dc=example,dc=com --bindpw Windows-secret --passsync secretpwd --cacert /etc/openldap/cacerts/windows.cer adserver.example.com -v
- When prompted, enter the Directory Manager password.
- Optional. Configure Password Synchronization, as in Section 15.6.2, “Setting up Password Synchronization”.
Option | Description |
---|---|
--winsync | Identifies this as a synchronization agreement. |
--binddn | Gives the full user DN of the synchronization identity. This is the user DN that the IdM LDAP server uses to bind to Active Directory. This user must exist in the Active Directory domain and must have replicator, read, search, and write permissions on the Active Directory subtree. |
--bindpw | Gives the password for the sync user. |
--passsync | Gives the password for the Windows user account which is involved in synchronization. |
--cacert | Gives the full path and file name of the Active Directory CA certificate. This certificate is exported in Section 15.5.1, “Trusting the Active Directory and IdM CA Certificates”. |
--win-subtree | Gives the DN of the Windows subtree containing the users to synchronize. The default value is cn=Users,$SUFFIX . |
AD_server_name | Gives the hostname of the Active Directory domain controller. |
15.5.3. Changing the Behavior for Syncing User Account Attributes
ldapmodify
command to modify the LDAP server entry directly.
ipaWinSyncAcctDisable
attribute. (Changing this means that if an account is disabled in Active Directory, it is still active in IdM and vice versa.)
[jsmith@ipaserver ~]$ ldapmodify -x -D "cn=directory manager" -w password dn: cn=ipa-winsync,cn=plugins,cn=config changetype: modify replace: ipaWinSyncAcctDisable ipaWinSyncAcctDisable: none modifying entry "cn=ipa-winsync,cn=plugins,cn=config"
Parameter | Description | Possible Values |
---|---|---|
General User Account Parameters | ||
ipaWinSyncNewEntryFilter | Sets the search filter to use to find the entry which contains the list of object classes to add to new user entries. | The default is (cn=ipaConfig) . |
ipaWinSyncNewUserOCAttr | Sets the attribute in the configuration entry which actually contains the list of object classes to add to new user entries. | The default is ipauserobjectclasses . |
ipaWinSyncHomeDirAttr | Identifies which attribute in the entry contains the default location of the POSIX home directory. | The default is ipaHomesRootDir . |
ipaWinSyncUserAttr | Sets an additional attribute with a specific value to add to Active Directory users when they are synced over from the Active Directory domain. If the attribute is multi-valued, then it can be set multiple times, and the sync process adds all of the values to the entry.
Note
This only sets the attribute value if the entry does not already have that attribute present. If the attribute is present, then the entry's value is used when the Active Directory entry is synced over.
| ipaWinSyncUserAttr: attributeName attributeValue |
ipaWinSyncForceSync | Sets whether to check existing IdM users which match an existing Active Directory user should be automatically edited so they can be synchronized. If an IdM user account has a uid parameter which is identical to the samAccountName in an existing Active Directory user, then that account is not synced by default. This attribute tells the sync service to add the ntUser and ntUserDomainId to the IdM user entries automatically, which allows them to be synchronized. | true | false |
User Account Lock Parameters | ||
ipaWinSyncAcctDisable | Sets which way to synchronize account lockout attributes. It is possible to control which account lockout settings are in effect. For example, to_ad means that when account lockout attribute is set in IdM, its value is synced over to Active Directory and overrides the local Active Directory value. By default, account lockout attributes are synced from both domains. |
|
ipaWinSyncInactivatedFilter | Sets the search filter to use to find the DN of the group used to hold inactivated (disabled) users. This does not need to be changed in most deployments. | The default is (&(cn=inactivated)(objectclass=groupOfNames)) . |
ipaWinSyncActivatedFilter | Sets the search filter to use to find the DN of the group used to hold active users. This does not need to be changed in most deployments. | The default is (&(cn=activated)(objectclass=groupOfNames)) . |
Group Parameters | ||
ipaWinSyncDefaultGroupAttr | Sets the attribute in the new user account to reference to see what the default group for the user is. The group name in the entry is then used to find the gidNumber for the user account. | The default is ipaDefaultPrimaryGroup . |
ipaWinSyncDefaultGroupFilter | Sets the search filter to map the group name to the POSIX gidNumber . | The default is (&(gidNumber=*)(objectclass=posixGroup)(cn= groupAttr_value)) . |
Realm Parameters | ||
ipaWinSyncRealmAttr | Sets the attribute which contains the realm name in the realm entry. | The default is cn . |
ipaWinSyncRealmFilter | Sets the search filter to use to find the entry which contains the IdM realm name. | The default is (objectclass=krbRealmContainer) . |
15.5.4. Changing the Synchronized Windows Subtree
cn=users,cn=accounts,$SUFFIX
, and for Active Directory, the default is CN=Users,$SUFFIX
.
--win-subtree
option. After the agreement is created, the Active Directory subtree can be changed by using the ldapmodify
command to edit the nsds7WindowsReplicaSubtree
value in the sync agreement entry.
- Get the name of the sync agreement, using
ldapsearch
. This search returns only the values for thedn
andnsds7WindowsReplicaSubtree
attributes instead of the entire entry.[jsmith@ipaserver ~]$ ldapsearch -xLLL -D "cn=directory manager" -w password -p 389 -h ipaserver.example.com -b cn=config objectclass=nsdswindowsreplicationagreement dn nsds7WindowsReplicaSubtree dn: cn=meToWindowsBox.example.com,cn=replica,cn=dc\3Dexample\2Cdc\3Dcom,cn=mapping tree,cn=config nsds7WindowsReplicaSubtree: cn=users,dc=example,dc=com ... 8< ...
- Modify the sync agreement
[jsmith@ipaserver ~]$ ldapmodify -x -D "cn=directory manager" -W -p 389 -h ipaserver.example.com <<EOF dn: cn=meToWindowsBox.example.com,cn=replica,cn=dc\3Dexample\2Cdc\3Dcom,cn=mapping tree,cn=config changetype: modify replace: nsds7WindowsReplicaSubtree nsds7WindowsReplicaSubtree: cn=alternateusers,dc=example,dc=com EOF modifying entry "cn=meToWindowsBox.example.com,cn=replica,cn=dc\3Dexample\2Cdc\3Dcom,cn=mapping tree,cn=config"
15.5.5. Configuring Uni-Directional Sync
oneWaySync
parameter on the sync agreement. The possible values are fromWindows
(for Active Directory to Identity Management sync) and toWindows
(for Identity Management to Active Directory sync).
[jsmith@ipaserver ~]$ ldapmodify -x -D "cn=directory manager" -w password -p 389 -h ipaserver.example.com dn: cn=windows.example.com,cn=replica,cn=dc\3Dexample\2Cdc\3Dcom,cn=mapping tree,cn=config changetype: modify add: oneWaySync oneWaySync: fromWindows
Important
15.5.6. Deleting Synchronization Agreements
ipa-replica-manage disconnect
command and then the hostname of the Active Directory server.
- Delete the sync agreement.
# ipa-replica-manage disconnect adserver.example.com
- Remove the Active Directory CA certificate from the IdM server database:
# certutil -D -d /etc/dirsrv/slapd-EXAMPLE.COM/ -n "Imported CA"
15.5.7. Winsync Agreement Failures
One of the most common sync agreement failures is that the IdM server cannot connect to the Active Directory server:
"Update failed! Status: [81 - LDAP error: Can't contact LDAP server]
/etc/dirsrv/slapd-DOMAIN/
directory) with the name Imported CA. This can be checked using certutil
:
$ certutil -L -d /etc/dirsrv/slapd-DOMAIN/ Certificate Nickname Trust Attributes SSL,S/MIME,JAR/XPI CA certificate CTu,u,Cu Imported CA CT,,C Server-Cert u,u,u Imported CA CT,,C
# certutil -d /etc/dirsrv/slapd-DOMAIN-NAME -D -n "Imported CA"
For some entries in the user database, there may be an informational error message that the password is not being reset because the entry already exists:
"Windows PassSync entry exists, not resetting password"
15.6. Managing Password Synchronization
Important
15.6.1. Setting up the Windows Server for Password Synchronization
- Active Directory must be running in SSL.
- The Password Sync Service must be installed on each Active Directory domain controller.
Note
- Make sure that the Active Directory password complexity policies are enabled so that the Password Sync service will run.
- Run
secpol.msc
from the command line. - Select.
- Open, and then open .
- Enable the
Password must meet complexity requirements
option and save.
- If SSL is not already enabled, set up SSL on the Active Directory server. Setting up LDAPS is explained in more detail in the Microsoft knowledgebase at http://support.microsoft.com/kb/321051.
- Install a certificate authority in the Windows Components section in Add/Remove Programs.
- Select the Enterprise Root CA option.
- Reboot the Active Directory server. If IIS web services are running, the CA certificate can be accessed by opening
http://
servername/certsrv
. - Set up the Active Directory server to use the SSL server certificate.
- Create a certificate request
.inf
, using the fully-qualified domain name of the Active Directory as the certificate subject. For example:;----------------- request.inf ----------------- [Version] Signature="$Windows NT$ [NewRequest] Subject = "CN=ad.server.example.com, O=Engineering, L=Raleigh, S=North Carolina, C=US" KeySpec = 1 KeyLength = 2048 Exportable = TRUE MachineKeySet = TRUE SMIME = False PrivateKeyArchive = FALSE UserProtected = FALSE UseExistingKeySet = FALSE ProviderName = "Microsoft RSA SChannel Cryptographic Provider" ProviderType = 12 RequestType = PKCS10 KeyUsage = 0xa0 [EnhancedKeyUsageExtension] OID=1.3.6.1.5.5.7.3.1 ;-----------------------------------------------
For more information on the.inf
request file, see the Microsoft documentation, such as http://technet.microsoft.com/en-us/library/cc783835.aspx. - Generate the certificate request.
certreq -new request.inf request.req
- Submit the request to the Active Directory CA. For example:
certreq -submit request.req certnew.cer
Note
If the command-line tool returns an error message, then use the Web browser to access the CA and submit the certificate request. If IIS is running, then the CA URL ishttp://
servername/certsrv
. - Accept the certificate request. For example:
certreq -accept certnew.cer
- Make sure that the server certificate is present on the Active Directory server.In themenu, click , then click and .
- Import the CA certificate from Directory Server into Active Directory. Click Trusted Root CA, then Import, and browse for the Directory Server CA certificate.
- Reboot the domain controller.
15.6.2. Setting up Password Synchronization
- Download the
PassSync.msi
file to the Active Directory machine.- Log into the Customer Portal.
- Click the Downloads tab.
- Click the Red Hat Enterprise Linux downloads button in the middle of the page.
- Filter the downloads by using a search term such as Directory Server, and then expand one of the Red Hat Enterprise Linux versions.
- Click the Directory Server link.
- On the Directory Server page, download the appropriate version of the WinSync Installer. This is the Password Sync MSI file (
RedHat-PassSync-1.1.5-arch.msi
).
Note
Regardless of the Red Hat Enterprise Linux architecture, there are two PassSync packages available, one for 32-bit Windows servers and one for 64-bit. Make sure to select the appropriate packages for your Windows platform. - Double-click the Password Sync MSI file to install it.
- The Password Sync Setup window appears. Hit Next to begin installing.
- Fill in the information to establish the connection to the IdM server.
- The IdM server connection information, including the hostname and secure port number.
- The username of the system user which Active Directory uses to connect to the IdM machine. This account is configured automatically when sync is configured on the IdM server. The default account is
uid=passsync,cn=sysaccounts,cn=etc,dc=example,dc=com
. - The password set in the
--passsync
option when the sync agreement was created. - The search base for the people subtree on the IdM server. The Active Directory server connects to the IdM server similar to an
ldapsearch
or replication operation, so it has to know where in the IdM subtree to look for user accounts. The user subtree iscn=users,cn=accounts,dc=example,dc=com
. - The certificate token is not used at this time, so that field should be left blank.
Hit, then to install Password Sync. - Import the IdM server's CA certificate into the Active Directory certificate store.
- Download the IdM server's CA certificate from
http://ipa.example.com/ipa/config/ca.crt
. - Copy the IdM CA certificate to the Active Directory server.
- Open the command prompt, using
Run as Administrator
. - Install the IdM CA certificate in the Password Sync database. For example:
cd "C:\Program Files\Red Hat Directory Password Synchronization" certutil.exe -d . -A -n "IPASERVER.EXAMPLE.COM IPA CA" -t CT,, -a -i ipaca.crt
cd "C:\Program Files\389 Directory Password Synchronization" certutil.exe -d . -A -n "IPASERVER.EXAMPLE.COM IPA CA" -t CT,, -a -i ipaca.crt
- Reboot the Windows machine to start Password Sync.
Note
The Windows machine must be rebooted. Without the rebooting,PasswordHook.dll
is not enabled, and password synchronization will not function.
.msi
.
15.6.3. Allowing Users to Change Other Users' Passwords Cleanly
passSyncManagersDNs
attribute lists administrator accounts which are allowed to perform password change operations and which will not then require a password reset.
Important
cn=ipa_pwd_extop,cn=plugins,cn=config
, and add the passSyncManagersDNs
attribute with the name of the user. This attribute is multi-valued. For example:
$ ldapmodify -x -D "cn=Directory Manager" -w secret -h ldap.example.com -p 389 dn: cn=ipa_pwd_extop,cn=plugins,cn=config changetype: modify add: passSyncManagersDNs passSyncManagersDNs: uid=admin,cn=users,cn=accounts,dc=example,dc=com
Warning
cn
is treated differently than other synced attributes. It is mapped directly (cn
to cn
) when syncing from Identity Management to Active Directory. When syncing from Active Directory to Identity Management, however, cn
is mapped from the name
attribute on Windows to the cn
attribute in Identity Management.
Chapter 16. Identity: ID Views and Migrating Existing Environments to Trust
Important
ipa-adtrust-install
command on the IdM server, the Default Trust View is created. The Default Trust View is always applied to Active Directory users and groups, which allows the administrator to define POSIX attributes for AD users and groups regardless of how AD itself defined them. If you add a host-specific ID view that overrides the AD users or groups, the attributes from the host-specific ID view are applied on top of the Default Trust View. While the new ID view overrides the Default Trust View, the default view itself cannot be deleted. If no specific ID view is applied to a client, the Default Trust View always applies.
Note
ipa-adtrust-install
is not run, you can still use the ID Views feature in a pure IdM environment to manage ID views and overrides for IdM users.
Note
- Store POSIX attributes and SSH keys for AD users
- Define POSIX attributes or SSH keys and SSH login information for AD users, and let them be applied when an AD user authenticates to clients running SSSD with ID Views support or when the AD user authenticates using a compat LDAP tree, which offers a simplified LDAP tree with user and group data for legacy clients.This capability is useful for migration from a synchronization-based solution or in a situation when a Linux administrator would like to manually define POSIX attributes for AD users but the AD policy does not allow it.
- Migrate from a synchronization-based to a trust-based integration
- Configure the POSIX attributes for users that are in a synchronization-based environment by creating an ID view override specifying previously used UID or other tools. Then move the users back to AD.
- Perform per-host group override of the IdM user POSIX attributes
- NIS-based infrastructure that is being migrated to an IdM integration with AD still often requires that the original POSIX data remain unchanged on some NIS domains or the company policies might prevent setting the original POSIX data in AD directly. In these situations, you can use ID Views to configure the POSIX data directly on the Identity Management server.
- Set different POSIX attributes or SSH keys for different environments
- Set different POSIX attributes or different user SSH public keys for different production environments – such as development, testing, or production – depending on the corresponding host groups.
16.1. User Overrides and Group Overrides
Note
uid
: user login nameuidNumber
: user UID numbergidNumber
: user GID numberloginShell
: user login shellgecos
: user GECOS entryhomeDirectory
: user home directoryipaSshPubkey
: user SSH public key or keys
cn
: group namegidNumber
: group GID number
Note
16.2. Managing ID Views on the Server Side
Important
16.3. ID Views on the Client Side
Important
Note
16.4. Migrating from the Synchronization-Based to the Trust-Based Solution
Chapter 17. Identity: Managing DNS
17.1. About DNS in IdM
dn: idnsname=client1,idnsname=example.com,cn=dns,dc=example,dc=com idnsname: client1 arecord: 10.0.0.1 arecord: 10.0.0.2 arecord: 10.0.0.3 aaaarecord: fc00::1 objectclass: top objectclass: idnsrecord
/usr/share/ipa/60basev2.ldif
schema file[6].
bind-dyndb-ldap
plug-in. When Identity Management is configured to manage DNS, IdM creates a dynamic-db
configuration section in the /etc/named.conf
file for the BIND service. This configures the bind-dyndb-ldap
plug-in for the BIND (named
) service.
named
service. The configuration can be changed to adapt the behavior of the plug-in and, therefore, the LDAP-BIND interactions.
17.2. Using IdM and DNS Service Discovery with an Existing DNS Configuration
Sample zone file for bind has been created in /tmp/sample.zone.F_uMf4.db
Example 17.1. Default IdM DNS File
; ldap servers _ldap._tcp IN SRV 0 100 389 ipaserver.example.com. ;kerberos realm _kerberos IN TXT EXAMPLE.COM ; kerberos servers _kerberos._tcp IN SRV 0 100 88 ipaserver.example.com. _kerberos._udp IN SRV 0 100 88 ipaserver.example.com. _kerberos-master._tcp IN SRV 0 100 88 ipaserver.example.com. _kerberos-master._udp IN SRV 0 100 88 ipaserver.example.com. _kpasswd._tcp IN SRV 0 100 464 ipaserver.example.com. _kpasswd._udp IN SRV 0 100 464 ipaserver.example.com.
Note
17.3. DNS Notes
- Wildcards cannot be used when configuring DNS names. Only explicit DNS domain names are supported.
- The
rndc
service is not configured by the--setup-dns
option. This service must be configured manually after the IdM server is configured.
17.4. Adding or Updating DNS Services After Installation
--setup-dns
option. If DNS is not configured then, it can be configured later using the ipa-dns-install
command.
ipa-dns-install
command also updates the DNS services on the IdM server.
[root@server ~]# ipa-dns-install -p secret --ip-address=1.2.34.56 --no-forwarders
-p
gives the password for the Directory Manager user in the 389 Directory Server. All of the DNS entries are stored in the LDAP directory, so this directory must be accessed to add the DNS configuration.--ip-address
gives the IP address for the master DNS server.--no-forwarders
means that there are no forwarders used with the DNS service, only root servers. Alternatively, use the--forwarder
option to define a forward to use; to specify multiple forwarders, use the--forwarder
option multiple times.- Reverse DNS is configured automatically. It is possible to disable reverse DNS by using the
--no-reverse
option.If an existing reverse DNS zone is already configured, using the--no-reverse
option uses the existing reverse zone rather than creating a new reverse zone. - The IdM server, unless it is explicitly disabled, leaves a persistent search open with its Directory Server and capture any new zone changes immediately.
17.5. Setting up the rndc Service
ipa-dns-install
command does not automatically configure the system's rndc
service. This must be configured manually, after DNS is configured for IdM.
- Create the
rndc
configuration file and key.[root@server ~]# /usr/sbin/rndc-confgen -a [root@server ~]# /sbin/restorecon /etc/rndc.conf
This may require some user input to create entropy while the key is being created. - Change the owner and permissions of the
rndc
key file.[root@server ~]# chown root:named /etc/rndc.key [root@server ~]# chmod 0640 /etc/rndc.key
17.6. Managing DNS Zone Entries
17.6.1. Adding Forward DNS Zones
17.6.1.1. From the Web UI
- Open the Identity tab, and select the DNS subtab.
- Click the Add link at the top of the list of DNS zones.
- Fill in the information about the new DNS zone. The Zone Name is required; this is the actual domain name. The other information about the administrator email and the authoritative name server are optional.
Note
If an email is given for the administrator, then replace the at symbol (@) with a period (.) to maintain compatibility with the zone file. - Click the Add and Edit button to go directly to the DNS zone page. In the Settings tab, it is possible to reset the default zone configuration to enable dynamic binds (Section 17.6.5.1, “Enabling Dynamic DNS Updates in the Web UI”) or change other default records information (Section 17.6.2.2, “Editing the Zone Configuration in the Web UI”). It is also possible to begin adding new DNS resource records (Section 17.7.1.1, “Adding DNS Resource Records from the Web UI”) in the DNS Resource Records tab.
17.6.1.2. From the Command Line
ipa dnszone-add
command adds a new zone to the DNS domain. At a minimum, this requires the name of the new subdomain:
$ ipa dnszone-add domainName
ipa dnszone-add
command.
- Add the new zone. For example:
[root@server ~]# ipa dnszone-add newserver.example.com --admin-email=admin@example.com --minimum=3000 --dynamic-update
- Reload the name service.
[root@server ~]# rndc reload
Note
To make new resource records immediately resolvable without restarting the name service, enable persistent searches with thenamed
service or configure the BIND service to poll the Directory Server automatically for zone changes. See Section 17.8.2, “Disabling Persistent Searches”.
17.6.2. Adding Additional Configuration for DNS Zones
Example 17.2. Default DNS Zone Entry Settings
[root@server ~]# ipa dnszone-show server.example.com Zone name: server.example.com Authoritative nameserver: dns.example.com Administrator e-mail address: admin.example.com. SOA serial: 1377691702 SOA refresh: 3600 SOA retry: 900 SOA expire: 1209600 SOA minimum: 3000 Active zone: TRUE Allow query: any; Allow transfer: none;
17.6.2.1. DNS Zone Configuration Attributes
Attribute | Command-Line Option | Description |
---|---|---|
Zone name | --name | Sets the name of the zone. |
Authoritative nameserver | --name-server | Sets the fully-qualified domain name of the DNS name server. |
Administrator e-mail address | --admin-email | Sets the email address to use for the zone administrator. This defaults to the root account on the host. |
SOA serial | --serial | Sets a version number for the SOA record file. |
SOA refresh | --refresh | Sets the interval, in seconds, for a secondary DNS server to wait before requesting updates from the primary DNS server. |
SOA retry | --retry | Sets the time, in seconds, to wait before retrying a failed refresh operation. |
SOA expire | --expire | Sets the time, in seconds, that a secondary DNS server will try to perform a refresh update before ending the operation attempt. |
SOA minimum | --minimum | Sets the minimum amount of time, in seconds, that data are kept in cache. |
SOA time to live | --ttl | Sets the maximum time, in seconds, that information is kept in the data cache. |
SOA class | --class | Sets the type of record. This is almost always IN, which stands for Internet. |
BIND update policy | --update-policy | Sets the permissions allowed to clients in the DNS zone. |
Dynamic update | --dynamic-update=TRUE|FALSE | Enables dynamic updates to DNS records for clients.
Important
If this is set to false, IdM client machines will not be able to add or update their IP address. See Section 17.6.5, “Enabling Dynamic DNS Updates” for more information.
|
Name server | --ip-address | Adds the DNS name server by its IP address. |
Allow transfer | --allow-transfer=string | Gives a semi-colon-separated list of IP addresses or network names which are allowed to transfer the given zone. |
Allow query | --allow-query | Gives a semi-colon-separated list of IP addresses or network names which are allowed to issue DNS queries. |
Allow PTR sync | --allow-sync-ptr=1|0 | Sets whether A or AAAA records (forward records) for the zone will be automatically synchronized with the PTR (reverse) records. |
Zone forwarders | --forwarder=string | Specifies a forwarder specifically configured for the DNS zone. This is separate from any global forwarders used in the IdM domain.
To specificy multiple forwarders, use the option multiple times.
|
Forward policy | --forward-policy=only|first | Sets whether the zone will only forward requests to configured the DNS name servers (a forward-only zone) or whether it will check the forwarders first for DNS records and then check its own local records. |
17.6.2.2. Editing the Zone Configuration in the Web UI
- Open the Identity tab, and select the DNS subtab.
- Click the name of the DNS zone to edit.
- Open the Settings tab.
- Change any of the DNS zone settings. The full list of attributes is described in Table 17.1, “Zone Attributes”. There are some common attributes to change:
- Authoritative name server, the fully-qualified domain name of the DNS name server.
- Dynamic update, to enable dynamic updates to DNS records for clients.
- SOA refresh, the interval, in seconds, for a secondary DNS server to wait before requesting updates from the primary DNS server.
- Click the Update link at the top of the settings page.
17.6.2.3. Editing the Zone Configuration in the Command Line
dnszone-add
command. Likewise, attributes can be added or modified in the zone entry by passing the same attribute options with the dnszone-mod
command. These are listed in Table 17.1, “Zone Attributes”.
dnszone-mod
command adds the attribute. If the attribute exists, then it overwrites the current value with the specified value.
[jsmith@server ~]$ kinit admin [jsmith@server ~]$ ipa dnszone-mod server.example.com --ttl=1800 Zone name: server.example.com Authoritative nameserver: dns.example.com Administrator e-mail address: admin.example.com. SOA serial: 1377691702 SOA refresh: 3600 SOA retry: 900 SOA expire: 1209600 SOA minimum: 3000 SOA time to live: 1800 Active zone: TRUE Allow query: any; Allow transfer: none;
17.6.3. Adding Reverse DNS Zones
- By zone name, in the format reverse_ip_address
.in-addr.arpa.
- By network address, in the format network_ip_address/subnet_mask_bit_count
Figure 17.1. Creating a Reverse Zone by Name
[bjensen@server ~]$ kinit [bjensen@server]$ ipa dnszone-add 206.65.10.in-addr.arpa.
Figure 17.2. Creating a Reverse Zone by IP Network
[bjensen@server ~]$ kinit [bjensen@server]$ ipa dnszone-add 10.65.206.0/24
17.6.4. Enabling and Disabling Zones
17.6.4.1. Disabling Zones in the Web UI
- Open the Identity tab, and select the DNS subtab.
- Click the name of the DNS zone to edit.
- Open the Settings tab.
- Scroll down to the Active zone field. To disable the zone, set the value to Disabled.
- Click the Update link at the top of the settings page.
17.6.4.2. Disabling Zones in the Command Line
dnszone-disable
command.
[jsmith@server ~]$ kinit admin [jsmith@server ~]$ ipa dnszone-disable server.example.com ----------------------------------------- Disabled DNS zone "server.example.com" -----------------------------------------
dnszone-enable
command.
17.6.5. Enabling Dynamic DNS Updates
ipa-client-install
script to join a client to the domain because it cannot add a DNS record pointing to the new client.
17.6.5.1. Enabling Dynamic DNS Updates in the Web UI
- Open the Identity tab, and select the DNS subtab.
- Click the name of the DNS zone to edit.
- Open the Settings tab.
- Scroll down to the Dynamic update field, and set the value to True.
- Click the Update link at the top of the settings page.
17.6.5.2. Enabling Dynamic DNS Updates in the Command Line
--dynamic-update
option.
$ ipa dnszone-mod server.example.com --dynamic-update=TRUE
17.6.6. Configuring Forwarders and Forward Policy
- A list of global forwarders which are used by all zones in IdM
- A list of forwarders which are used by a single, specific zone (as part of the zone configuration)
- A policy which defines how the zone sends requests to the forwarders
17.6.6.1. Configuring Forwarders in the UI
- To add a forwarder, fill in the field or click Add to add a new IP address to the forwarder list.
- By default, the zone uses the forwarders only for servicing name resolution requests; this is called a forward-only zone. A forward-only zone does not check its own name records. Only the forwarder server records are checked. If the record does not exist on the configured forwarders, then the zone returns a negative response to the client. Alternatively, the zone can check the forwarder records first, and then fallback on its own resource records. This has a first policy.
Figure 17.3. Forwarders in the DNS Zone Configuration
17.6.6.2. Configuring Forwarders in the Command Line
dnszone-mod
command to update the zone settings. This can be used to set the list of DNS forwarders and the forwarding policy, as in the UI.
dnsconfig
command can be used to set a global list of forwarders for all zones by editing the DNS configuration files.
Example 17.3. Configuring Global Forwarders
setup-dns
option or when the ipa-dns-install
script is used.
dnsconfig-mod
command. For example:
[jsmith@server ~]$ ipa dnsconfig-mod --forwarder=0.9.8.7 Global forwarders: 0.9.8.7
Example 17.4. Configuring Zone Forwarders
--forwarder
option can be used multiple times to create a list of forwarders to use with the zone.
[jsmith@server ~]$ ipa dnszone-mod --forwarder=192.0.2.0 --forwarder=198.51.100.0 example.com Zone name: example.com ... Zone forwarders: 192.0.2.0, 198.51.100.0
Note
Example 17.5. Configuring Forwarder Policy for a Zone
--forward-policy
option, using a policy of either only
or first
. For example:
[jsmith@server ~]$ ipa dnszone-mod --forward-policy=only example.com Zone name: example.com ... Zone forwarders: 1.2.3.4;5.6.7.8 Forward policy: only
17.6.7. Enabling Zone Transfers
17.6.7.1. Enabling Zone Transfers in the UI
Figure 17.4. DNS Zone Transfer Settings
17.6.7.2. Enabling Zone Transfers in the Command Line
--allow-transfer
option to set a list of name servers to which the zone records can be transferred.
[jsmith@server ~]$ ipa dnszone-mod --allow-transfer="0.0.0.0;1.2.3.4;5.6.7.8" example-zone
any
, which the zone to be transferred anywhere in the DNS domain.
bind
service, IdM DNS zones can be transferred, by name, by clients like dig
:
[root@server ~]# dig @ipa-server zone_name AXFR
17.6.8. Defining DNS Queries
--allow-query
option to set a list of clients which are allowed to issue queries.
[jsmith@server ~]$ ipa dnszone-mod --allow-query=0.0.0.0;1.2.3.4;5.6.7.8 example-zone
any
, which allows the zone to be queried by any client.
17.6.9. Synchronizing Forward and Reverse Zone Entries
- Both forward and reverse zones must be managed by the IdM server.
- Both zones must have dynamic updates enabled.Enabling dynamic updates is covered in Section 17.6.5, “Enabling Dynamic DNS Updates”.
- The PTR record will be updated only if the name of the requesting client matches the name in the PTR record.
Important
Warning
17.6.9.1. Configuring Zone Entry Sync in the UI
Note
Figure 17.5. DNS Zone Sync Settings
17.6.9.2. Configuring Zone Entry Sync in the Command Line
--allow-sync-ptr
option to 1
. This can be done when the zone is created or when it is edited.
Note
[jsmith@server ~]$ ipa dnszone-mod --allow-sync-ptr=1 example-zone
0
, which disables synchronization and has better server performance.
17.6.10. Setting DNS Access Policies
update-policy
statement in the /etc/named.conf
file, which defines the DNS access rule.
Important
17.6.10.1. Setting DNS Access Policies in the UI
grant|deny zoneName policyName recordName recordType
Figure 17.6. DNS Update Policy Settings
17.6.10.2. Setting DNS Access Policies in the Command Line
--update-policy
option, with the access control rule in a statement after it.
--update-policy "grant|deny zoneName policyName recordName recordType"
- zoneName is the IdM DNS zone to which to apply the rule.
- policyName is the name to use for the BIND rule.
- recordName sets the resource records to which to apply the rule. Using an asterisk (*) is used for self rules.
- recordType is the record type the rule applies to. Update access rules are applied individually for each record type, even within the same DNS zone entry.The full list of supported record types is in Table 17.2, “DNS Record Types”.
EXAMPLE.COM
zone the ability to edit its own A and AAAA resource record entries:
$ ipa dnszone-mod example.com --update-policy="grant EXAMPLE.COM krb5-self * A; grant EXAMPLE.COM krb5-self * AAAA;"
17.7. Managing DNS Record Entries
17.7.1. Adding Records to DNS Zones
A | CERT | KX | NS | SIG |
AAAA | CNAME | LOC | NSEC | SRV |
A6 | DNAME | MX | PTR | SSHFP |
AFSDB | DS | NAPTR | RRSIG | TXT |
17.7.1.1. Adding DNS Resource Records from the Web UI
Note
named
service or configure the BIND service to poll the Directory Server automatically for zone changes. See Section 17.8.2, “Disabling Persistent Searches”.
- Open the Identity tab, and select the DNS subtab.
- Click the name of the DNS zone to which to add records.
- In the DNS Resource Records tab, click the Add link.
- Select the type of record to create in the Record Type drop-down menu. The required data is different, depending on the record type. For example, a CNAME record requires a hostname. The data field name updates automatically to indicate what kind of information to supply.Although IdM supports many different record types, there are four frequent record types that are used:
- A. This is a basic map for a hostname and an ordinary IPv4 address. The Record Name is a hostname, such as www. The IP Address value is a standard IPv4 address, such as 192.168.1.2.More information about A records is in RFC 1035.
- AAAA. This is a basic map for a hostname and an IPv6 address. The Record Name is a hostname, such as www. The IP Address value is a standard hexadecimal IPv6 address, such as fe80::20c:29ff:fe02:a1b3.More information about AAAA records is in RFC 3596.
- SRV. Service (SRV) resource records map service names to the DNS name of the server that is providing that particular service. The Record Name has the format _service._protocol, such as _ldap._tcp. There are individual fields to set the priority, weight, port number, and hostname for the target service.More information about SRV records is in RFC 2782.
- PTR. A pointer record type (PTR) record adds a reverse DNS record, which maps an IP address to a domain name. In this case, the Record Name is the record ID number for the DNS entry of the resource and the Hostname value is the hostname with a terminal period, such as server.example.com..More information about PTR records is in RFC 1035.
- Click thebutton to save the new resource record.
17.7.1.2. Adding DNS Resource Records from the Command Line
ipa dnsrecord-add
, is used to add resource records of any type, but the options for the script and the required data are different, based on the resource record type.
17.7.1.2.1. About the Commands to Add DNS Records
ipa dnsrecord-add
command adds records to DNS zones, based on the type. Adding a record has the same basic command format:
$ ipa dnsrecord-add zoneName recordName --recordType-option=data
ipa dnsrecord-add
help and manpages.
Note
ipa dnsrecord-add
command only creates forward entries, not reverse entries.
General Record Options | |
---|---|
Option | Description |
--ttl=number | Sets the time to live for the record. |
--class=IN | CS | CH | HS | Sets the class of the record. This is usually IN, for Internet protocol. |
--structured | Parses the raw DNS records and returns them in a structured format. |
"A" Record Options | |
---|---|
Option | Description |
--a-rec=ARECORD | Passes a comma-separated list of A records. |
--a-ip-address=string | Gives the IP address for the record. |
"AAAA" Record Options | |
---|---|
Option | Description |