Red Hat SummitChapter 13. Managing Kerberos principal aliases for users, hosts, and services
When you create a new user, host, or service, a Kerberos principal in the following format is automatically added:
- user_name@REALM
- host/host_name@REALM
- service_name/host_name@REALM
Administrators can enable users, hosts, or services to authenticate against Kerberos applications using an alias. This is beneficial in the following scenarios:
- The user name changed and the user wants to log in using both the previous and new user name.
- The user needs to log in using the email address even if the IdM Kerberos realm differs from the email domain.
Note that if you rename a user, the object keeps the aliases and the previous canonical principal name.
13.1. Adding a Kerberos principal alias
You can associate alias names with existing Kerberos principals in an Identity Management (IdM) environment. This enhances security and simplifies authentication processes within the IdM domain.
Procedure
To add the alias name
useraliasto the accountuser, enter:# ipa user-add-principal <user> <useralias> -------------------------------- Added new aliases to user "user" -------------------------------- User login: user Principal alias: user@IDM.EXAMPLE.COM, useralias@IDM.EXAMPLE.COMTo add an alias to a host or service, use the
ipa host-add-principaloripa service-add-principalcommand respectively instead.If you use an alias name to authenticate, use the
-Coption with thekinitcommand:# kinit -C <useralias> Password for <user>@IDM.EXAMPLE.COM:
13.2. Removing a Kerberos principal alias
You can remove alias names associated with Kerberos principals in their Identity Management (IdM) environment.
Procedure
To remove the alias
useraliasfrom the accountuser, enter:# ipa user-remove-principal <user> <useralias> -------------------------------- Removed aliases from user "user" -------------------------------- User login: user Principal alias: user@IDM.EXAMPLE.COMTo remove an alias from a host or service, use the
ipa host-remove-principaloripa service-remove-principalcommand respectively instead.Note that you cannot remove the canonical principal name:
# ipa user-show <user> User login: user ... Principal name: user@IDM.EXAMPLE.COM ... # ipa user-remove-principal user user ipa: ERROR: invalid 'krbprincipalname': at least one value equal to the canonical principal name must be present
13.3. Adding a Kerberos enterprise principal alias
You can associate enterprise principal alias names with existing Kerberos enterprise principals in an Identity Management (IdM) environment. Enterprise principal aliases can use any domain suffix except for user principal name (UPN) suffixes, NetBIOS names, or domain names of trusted Active Directory forest domains.
When adding or removing enterprise principal aliases, escape the @ symbol using two backslashes (\\). Otherwise, the shell interprets the @ symbol as part of the Kerberos realm name and leads to the following error:
ipa: ERROR: The realm for the principal does not match the realm for this IPA server
Procedure
To add the enterprise principal alias
user@example.comto theuseraccount:# ipa user-add-principal <user> <user\\@example.com> -------------------------------- Added new aliases to user "user" -------------------------------- User login: user Principal alias: user@IDM.EXAMPLE.COM, user\@example.com@IDM.EXAMPLE.COMTo add an enterprise alias to a host or service, use the
ipa host-add-principaloripa service-add-principalcommand respectively instead.If you use an enterprise principal name to authenticate, use the
-Eoption with thekinitcommand:# kinit -E <user@example.com> Password for user\@example.com@IDM.EXAMPLE.COM:
13.4. Removing a Kerberos enterprise principal alias
You can remove enterprise principal alias names associated with Kerberos enterprise principals in their Identity Management (IdM) environment.
When adding or removing enterprise principal aliases, escape the @ symbol using two backslashes (\\). Otherwise, the shell interprets the @ symbol as part of the Kerberos realm name and leads to the following error:
ipa: ERROR: The realm for the principal does not match the realm for this IPA server
Procedure
To remove the enterprise principal alias
user@example.comfrom the accountuser, enter:# ipa user-remove-principal <user> <user\\@example.com> -------------------------------- Removed aliases from user "user" -------------------------------- User login: user Principal alias: user@IDM.EXAMPLE.COMTo remove an alias from a host or service, use the
ipa host-remove-principaloripa service-remove-principalcommand respectively instead.
