第 1 章 Installing on IBM Z
1.1. Installing a cluster on IBM Z and LinuxONE
In OpenShift Container Platform version 4.5, you can install a cluster on IBM Z or LinuxONE infrastructure that you provision.
While this document refers only to IBM Z, all information in it also applies to LinuxONE.
Additional considerations exist for non-bare metal platforms. Review the information in the guidelines for deploying OpenShift Container Platform on non-tested platforms before you install an OpenShift Container Platform cluster.
1.1.1. Prerequisites
- Before you begin the installation process, you must move or remove any existing installation files. This ensures that the required installation files are created and updated during the installation process.
-
Provision persistent storage using NFS for your cluster. To deploy a private image registry, your storage must provide
ReadWriteMany
access modes. - Review details about the OpenShift Container Platform installation and update processes.
If you use a firewall, you must configure it to allow the sites that your cluster requires access to.
注意Be sure to also review this site list if you are configuring a proxy.
1.1.2. Internet and Telemetry access for OpenShift Container Platform
In OpenShift Container Platform 4.5, you require access to the Internet to install your cluster. The Telemetry service, which runs by default to provide metrics about cluster health and the success of updates, also requires Internet access. If your cluster is connected to the Internet, Telemetry runs automatically, and your cluster is registered to the Red Hat OpenShift Cluster Manager (OCM).
Once you confirm that your Red Hat OpenShift Cluster Manager inventory is correct, either maintained automatically by Telemetry or manually using OCM, use subscription watch to track your OpenShift Container Platform subscriptions at the account or multi-cluster level.
You must have Internet access to:
- Access the Red Hat OpenShift Cluster Manager page to download the installation program and perform subscription management. If the cluster has Internet access and you do not disable Telemetry, that service automatically entitles your cluster.
- Access Quay.io to obtain the packages that are required to install your cluster.
- Obtain the packages that are required to perform cluster updates.
If your cluster cannot have direct Internet access, you can perform a restricted network installation on some types of infrastructure that you provision. During that process, you download the content that is required and use it to populate a mirror registry with the packages that you need to install a cluster and generate the installation program. With some installation types, the environment that you install your cluster in will not require Internet access. Before you update the cluster, you update the content of the mirror registry.
1.1.3. Machine requirements for a cluster with user-provisioned infrastructure
For a cluster that contains user-provisioned infrastructure, you must deploy all of the required machines.
1.1.3.1. Required machines
The smallest OpenShift Container Platform clusters require the following hosts:
- One temporary bootstrap machine
- Three control plane, or master, machines
- At least two compute machines, which are also known as worker machines.
The cluster requires the bootstrap machine to deploy the OpenShift Container Platform cluster on the three control plane machines. You can remove the bootstrap machine after you install the cluster.
To improve high availability of your cluster, distribute the control plane machines over different z/VM instances on at least two physical machines.
The bootstrap and control plane machines must use Red Hat Enterprise Linux CoreOS (RHCOS) as the operating system.
Note that RHCOS is based on Red Hat Enterprise Linux (RHEL) 8 and inherits all of its hardware certifications and requirements. See Red Hat Enterprise Linux technology capabilities and limits.
1.1.3.2. Network connectivity requirements
All the Red Hat Enterprise Linux CoreOS (RHCOS) machines require network in initramfs
during boot to fetch Ignition config files from the Machine Config Server. The machines are configured with static IP addresses. No DHCP server is required. Additionally, each OpenShift Container Platform node in the cluster must have access to a Network Time Protocol (NTP) server.
1.1.3.3. IBM Z network connectivity requirements
To install on IBM Z under z/VM, you require a single z/VM virtual NIC in layer 2 mode. You also need:
- A direct-attached OSA or RoCE network adapter
- A z/VM VSWITCH set up. For a preferred setup, use OSA link aggregation.
1.1.3.4. Minimum resource requirements
Each cluster machine must meet the following minimum requirements:
Machine | Operating System | vCPU [1] | Virtual RAM | Storage |
---|---|---|---|---|
Bootstrap | RHCOS | 4 | 16 GB | 120 GB |
Control plane | RHCOS | 4 | 16 GB | 120 GB |
Compute | RHCOS | RHCOS or RHEL 7.8 - 7.9 | 2 | 8 GB |
- 1 vCPU is equivalent to 1 physical core when simultaneous multithreading (SMT), or hyperthreading, is not enabled. When enabled, use the following formula to calculate the corresponding ratio: (threads per core × cores) × sockets = vCPUs.
1.1.3.5. Minimum IBM Z system requirements
You can install OpenShift Container Platform version 4.5 on the following IBM hardware:
- IBM Z: z13, z13s, all z14 models, all z15 models
- LinuxONE: all models
Hardware requirements
- 1 LPAR with 3 IFLs that supports SMT2
- 1 OSA or RoCE network adapter
Operating system requirements
- One instance of z/VM 7.1
On your z/VM instance, set up:
- 3 guest virtual machines for OpenShift Container Platform control plane machines
- 2 guest virtual machines for OpenShift Container Platform compute machines
- 1 guest virtual machine for the temporary OpenShift Container Platform bootstrap machine
Disk storage for the z/VM guest virtual machines
- FICON attached disk storage (DASDs). These can be z/VM minidisks, fullpack minidisks, or dedicated DASDs, all of which must be formatted as CDL, which is the default. To reach the minimum required DASD size for Red Hat Enterprise Linux CoreOS (RHCOS) installations, you need extended address volumes (EAV). If available, use HyperPAV to ensure optimal performance.
- FCP attached disk storage
Storage / Main Memory
- 16 GB for OpenShift Container Platform control plane machines
- 8 GB for OpenShift Container Platform compute machines
- 16 GB for the temporary OpenShift Container Platform bootstrap machine
1.1.3.6. Preferred IBM Z system requirements
Hardware requirements
- 3 LPARs with 6 IFLs each that support SMT2
- 1 or 2 OSA or RoCE network adapters, or both
- Hipersockets, which are attached to a node either directly as a device or by bridging with one z/VM VSWITCH to be transparent to the z/VM guest. To directly connect Hipersockets to a node, you must set up a gateway to the external network via a RHEL 8 guest to bridge to the Hipersockets network.
Operating system requirements
- 2 or 3 instances of z/VM 7.1 for high availability
On your z/VM instances, set up:
- 3 guest virtual machines for OpenShift Container Platform control plane machines, one per z/VM instance
- At least 6 guest virtual machines for OpenShift Container Platform compute machines, distributed across the z/VM instances
- 1 guest virtual machine for the temporary OpenShift Container Platform bootstrap machine
Disk storage for the z/VM guest virtual machines
- FICON attached disk storage (DASDs). These can be z/VM minidisks, fullpack minidisks, or dedicated DASDs, all of which must be formatted as CDL, which is the default. To reach the minimum required DASD size for Red Hat Enterprise Linux CoreOS (RHCOS) installations, you need extended address volumes (EAV). If available, use HyperPAV and High Performance FICON (zHPF) to ensure optimal performance.
- FCP attached disk storage
Storage / Main Memory
- 16 GB for OpenShift Container Platform control plane machines
- 8 GB for OpenShift Container Platform compute machines
- 16 GB for the temporary OpenShift Container Platform bootstrap machine
1.1.3.7. Certificate signing requests management
Because your cluster has limited access to automatic machine management when you use infrastructure that you provision, you must provide a mechanism for approving cluster certificate signing requests (CSRs) after installation. The kube-controller-manager
only approves the kubelet client CSRs. The machine-approver
cannot guarantee the validity of a serving certificate that is requested by using kubelet credentials because it cannot confirm that the correct machine issued the request. You must determine and implement a method of verifying the validity of the kubelet serving certificate requests and approving them.
Additional resources
- See Bridging a HiperSockets LAN with a z/VM Virtual Switch in the IBM Knowledge Center.
- See Scaling HyperPAV alias devices on Linux guests on z/VM for performance optimization.
1.1.4. Creating the user-provisioned infrastructure
Before you deploy an OpenShift Container Platform cluster that uses user-provisioned infrastructure, you must create the underlying infrastructure.
Prerequisites
- Review the OpenShift Container Platform 4.x Tested Integrations page before you create the supporting infrastructure for your cluster.
Procedure
- Set up static IP addresses.
- Set up an FTP server.
- Provision the required load balancers.
- Configure the ports for your machines.
- Configure DNS.
- Ensure network connectivity.
1.1.4.1. Networking requirements for user-provisioned infrastructure
All the Red Hat Enterprise Linux CoreOS (RHCOS) machines require network in initramfs
during boot to fetch Ignition config from the machine config server.
During the initial boot, the machines require an FTP server in order to establish a network connection to download their Ignition config files.
Ensure that the machines have persistent IP addresses and host names.
The Kubernetes API server, which runs on each master node after a successful cluster installation, must be able to resolve the node names of the cluster machines. If the API servers and worker nodes are in different zones, you can configure a default DNS search zone to allow the API server to resolve the node names. Another supported approach is to always refer to hosts by their fully-qualified domain names in both the node objects and all DNS requests.
You must configure the network connectivity between machines to allow cluster components to communicate. Each machine must be able to resolve the host names of all other machines in the cluster.
Protocol | Port | Description |
---|---|---|
ICMP | N/A | Network reachability tests |
TCP |
| Metrics |
|
Host level services, including the node exporter on ports | |
| The default ports that Kubernetes reserves | |
| openshift-sdn | |
UDP |
| VXLAN and Geneve |
| VXLAN and Geneve | |
|
Host level services, including the node exporter on ports | |
TCP/UDP |
| Kubernetes node port |
Protocol | Port | Description |
---|---|---|
TCP |
| Kubernetes API |
Protocol | Port | Description |
---|---|---|
TCP |
| etcd server and peer ports |
Network topology requirements
The infrastructure that you provision for your cluster must meet the following network topology requirements.
OpenShift Container Platform requires all nodes to have internet access to pull images for platform containers and provide telemetry data to Red Hat.
Load balancers
Before you install OpenShift Container Platform, you must provision two load balancers that meet the following requirements:
API load balancer: Provides a common endpoint for users, both human and machine, to interact with and configure the platform. Configure the following conditions:
- Layer 4 load balancing only. This can be referred to as Raw TCP, SSL Passthrough, or SSL Bridge mode. If you use SSL Bridge mode, you must enable Server Name Indication (SNI) for the API routes.
- A stateless load balancing algorithm. The options vary based on the load balancer implementation.
注意Session persistence is not required for the API load balancer to function properly.
Configure the following ports on both the front and back of the load balancers:
表 1.4. API load balancer Port Back-end machines (pool members) Internal External Description 6443
Bootstrap and control plane. You remove the bootstrap machine from the load balancer after the bootstrap machine initializes the cluster control plane. You must configure the
/readyz
endpoint for the API server health check probe.X
X
Kubernetes API server
22623
Bootstrap and control plane. You remove the bootstrap machine from the load balancer after the bootstrap machine initializes the cluster control plane.
X
Machine config server
注意The load balancer must be configured to take a maximum of 30 seconds from the time the API server turns off the
/readyz
endpoint to the removal of the API server instance from the pool. Within the time frame after/readyz
returns an error or becomes healthy, the endpoint must have been removed or added. Probing every 5 or 10 seconds, with two successful requests to become healthy and three to become unhealthy, are well-tested values.Application Ingress load balancer: Provides an Ingress point for application traffic flowing in from outside the cluster. Configure the following conditions:
- Layer 4 load balancing only. This can be referred to as Raw TCP, SSL Passthrough, or SSL Bridge mode. If you use SSL Bridge mode, you must enable Server Name Indication (SNI) for the Ingress routes.
- A connection-based or session-based persistence is recommended, based on the options available and types of applications that will be hosted on the platform.
Configure the following ports on both the front and back of the load balancers:
表 1.5. Application Ingress load balancer Port Back-end machines (pool members) Internal External Description 443
The machines that run the Ingress router pods, compute, or worker, by default.
X
X
HTTPS traffic
80
The machines that run the Ingress router pods, compute, or worker, by default.
X
X
HTTP traffic
If the true IP address of the client can be seen by the load balancer, enabling source IP-based session persistence can improve performance for applications that use end-to-end TLS encryption.
A working configuration for the Ingress router is required for an OpenShift Container Platform cluster. You must configure the Ingress router after the control plane initializes.
NTP configuration
OpenShift Container Platform clusters are configured to use a public Network Time Protocol (NTP) server by default. If you want to use a local enterprise NTP server, or if your cluster is being deployed in a disconnected network, you can configure the cluster to use a specific time server. For more information, see the documentation for Configuring chrony time service.
Additional resources
1.1.4.2. User-provisioned DNS requirements
DNS is used for name resolution and reverse name resolution. DNS A/AAAA or CNAME records are used for name resolution and PTR records are used for reverse name resolution. The reverse records are important because Red Hat Enterprise Linux CoreOS (RHCOS) uses the reverse records to set the host name for all the nodes. Additionally, the reverse records are used to generate the certificate signing requests (CSR) that OpenShift Container Platform needs to operate.
The following DNS records are required for an OpenShift Container Platform cluster that uses user-provisioned infrastructure. In each record, <cluster_name>
is the cluster name and <base_domain>
is the cluster base domain that you specify in the install-config.yaml
file. A complete DNS record takes the form: <component>.<cluster_name>.<base_domain>.
.
Component | Record | Description |
---|---|---|
Kubernetes API |
| Add a DNS A/AAAA or CNAME record, and a DNS PTR record, to identify the load balancer for the control plane machines. These records must be resolvable by both clients external to the cluster and from all the nodes within the cluster. |
| Add a DNS A/AAAA or CNAME record, and a DNS PTR record, to identify the load balancer for the control plane machines. These records must be resolvable from all the nodes within the cluster. 重要 The API server must be able to resolve the worker nodes by the host names that are recorded in Kubernetes. If the API server cannot resolve the node names, then proxied API calls can fail, and you cannot retrieve logs from pods. | |
Routes |
| Add a wildcard DNS A/AAAA or CNAME record that refers to the load balancer that targets the machines that run the Ingress router pods, which are the worker nodes by default. These records must be resolvable by both clients external to the cluster and from all the nodes within the cluster. |
Bootstrap |
| Add a DNS A/AAAA or CNAME record, and a DNS PTR record, to identify the bootstrap machine. These records must be resolvable by the nodes within the cluster. |
Master hosts |
| Add DNS A/AAAA or CNAME records and DNS PTR records to identify each machine for the master nodes. These records must be resolvable by the nodes within the cluster. |
Worker hosts |
| Add DNS A/AAAA or CNAME records and DNS PTR records to identify each machine for the worker nodes. These records must be resolvable by the nodes within the cluster. |
You can use the nslookup <hostname>
command to verify name resolution. You can use the dig -x <ip_address>
command to verify reverse name resolution for the PTR records.
The following example of a BIND zone file shows sample A records for name resolution. The purpose of the example is to show the records that are needed. The example is not meant to provide advice for choosing one name resolution service over another.
例 1.1. Sample DNS zone database
$TTL 1W @ IN SOA ns1.example.com. root ( 2019070700 ; serial 3H ; refresh (3 hours) 30M ; retry (30 minutes) 2W ; expiry (2 weeks) 1W ) ; minimum (1 week) IN NS ns1.example.com. IN MX 10 smtp.example.com. ; ; ns1 IN A 192.168.1.5 smtp IN A 192.168.1.5 ; helper IN A 192.168.1.5 helper.ocp4 IN A 192.168.1.5 ; ; The api identifies the IP of your load balancer. api.ocp4 IN A 192.168.1.5 api-int.ocp4 IN A 192.168.1.5 ; ; The wildcard also identifies the load balancer. *.apps.ocp4 IN A 192.168.1.5 ; ; Create an entry for the bootstrap host. bootstrap.ocp4 IN A 192.168.1.96 ; ; Create entries for the master hosts. master0.ocp4 IN A 192.168.1.97 master1.ocp4 IN A 192.168.1.98 master2.ocp4 IN A 192.168.1.99 ; ; Create entries for the worker hosts. worker0.ocp4 IN A 192.168.1.11 worker1.ocp4 IN A 192.168.1.7 ; ;EOF
The following example BIND zone file shows sample PTR records for reverse name resolution.
例 1.2. Sample DNS zone database for reverse records
$TTL 1W @ IN SOA ns1.example.com. root ( 2019070700 ; serial 3H ; refresh (3 hours) 30M ; retry (30 minutes) 2W ; expiry (2 weeks) 1W ) ; minimum (1 week) IN NS ns1.example.com. ; ; The syntax is "last octet" and the host must have an FQDN ; with a trailing dot. 97 IN PTR master0.ocp4.example.com. 98 IN PTR master1.ocp4.example.com. 99 IN PTR master2.ocp4.example.com. ; 96 IN PTR bootstrap.ocp4.example.com. ; 5 IN PTR api.ocp4.example.com. 5 IN PTR api-int.ocp4.example.com. ; 11 IN PTR worker0.ocp4.example.com. 7 IN PTR worker1.ocp4.example.com. ; ;EOF
1.1.5. Generating an SSH private key and adding it to the agent
If you want to perform installation debugging or disaster recovery on your cluster, you must provide an SSH key to both your ssh-agent
and the installation program. You can use this key to access the bootstrap machine in a public cluster to troubleshoot installation issues.
In a production environment, you require disaster recovery and debugging.
Do not skip this procedure in production environments where disaster recovery and debugging is required.
You can use this key to SSH into the master nodes as the user core
. When you deploy the cluster, the key is added to the core
user’s ~/.ssh/authorized_keys
list.
You must use a local key, not one that you configured with platform-specific approaches such as AWS key pairs.
Procedure
If you do not have an SSH key that is configured for password-less authentication on your computer, create one. For example, on a computer that uses a Linux operating system, run the following command:
$ ssh-keygen -t ed25519 -N '' \ -f <path>/<file_name> 1
- 1
- Specify the path and file name, such as
~/.ssh/id_rsa
, of the new SSH key. If you have an existing key pair, ensure your public key is in the your~/.ssh
directory.
Running this command generates an SSH key that does not require a password in the location that you specified.
注意If you plan to install an OpenShift Container Platform cluster that uses FIPS Validated / Modules in Process cryptographic libraries on the
x86_64
architecture, do not create a key that uses theed25519
algorithm. Instead, create a key that uses thersa
orecdsa
algorithm.Start the
ssh-agent
process as a background task:$ eval "$(ssh-agent -s)"
Example output
Agent pid 31874
Add your SSH private key to the
ssh-agent
:$ ssh-add <path>/<file_name> 1
Example output
Identity added: /home/<you>/<path>/<file_name> (<computer_name>)
- 1
- Specify the path and file name for your SSH private key, such as
~/.ssh/id_rsa
Next steps
- When you install OpenShift Container Platform, provide the SSH public key to the installation program.
1.1.6. Obtaining the installation program
Before you install OpenShift Container Platform, download the installation file on your provisioning machine.
Prerequisites
- You must install the cluster from a machine that runs Linux, for example Red Hat Enterprise Linux 8.
- You need 500 MB of local disk space to download the installation program.
Procedure
- Access the Infrastructure Provider page on the Red Hat OpenShift Cluster Manager site. If you have a Red Hat account, log in with your credentials. If you do not, create an account.
Navigate to the page for your installation type, download the installation program for your operating system, and place the file in the directory where you will store the installation configuration files.
重要The installation program creates several files on the computer that you use to install your cluster. You must keep both the installation program and the files that the installation program creates after you finish installing the cluster.
重要Deleting the files created by the installation program does not remove your cluster, even if the cluster failed during installation. You must complete the OpenShift Container Platform uninstallation procedures outlined for your specific cloud provider to remove your cluster entirely.
Extract the installation program. For example, on a computer that uses a Linux operating system, run the following command:
$ tar xvf <installation_program>.tar.gz
-
From the Pull Secret page on the Red Hat OpenShift Cluster Manager site, download your installation pull secret as a
.txt
file. This pull secret allows you to authenticate with the services that are provided by the included authorities, including Quay.io, which serves the container images for OpenShift Container Platform components.
1.1.7. Installing the CLI by downloading the binary
You can install the OpenShift CLI (oc
) in order to interact with OpenShift Container Platform from a command-line interface. You can install oc
on Linux, Windows, or macOS.
If you installed an earlier version of oc
, you cannot use it to complete all of the commands in OpenShift Container Platform 4.5. Download and install the new version of oc
.
1.1.7.1. Installing the CLI on Linux
You can install the OpenShift CLI (oc
) binary on Linux by using the following procedure.
Procedure
- Navigate to the Infrastructure Provider page on the Red Hat OpenShift Cluster Manager site.
- Select your infrastructure provider, and, if applicable, your installation type.
- In the Command line interface section, select Linux from the drop-down menu and click Download command-line tools.
Unpack the archive:
$ tar xvzf <file>
Place the
oc
binary in a directory that is on yourPATH
.To check your
PATH
, execute the following command:$ echo $PATH
After you install the CLI, it is available using the oc
command:
$ oc <command>
1.1.7.2. Installing the CLI on Windows
You can install the OpenShift CLI (oc
) binary on Windows by using the following procedure.
Procedure
- Navigate to the Infrastructure Provider page on the Red Hat OpenShift Cluster Manager site.
- Select your infrastructure provider, and, if applicable, your installation type.
- In the Command line interface section, select Windows from the drop-down menu and click Download command-line tools.
- Unzip the archive with a ZIP program.
Move the
oc
binary to a directory that is on yourPATH
.To check your
PATH
, open the command prompt and execute the following command:C:\> path
After you install the CLI, it is available using the oc
command:
C:\> oc <command>
1.1.7.3. Installing the CLI on macOS
You can install the OpenShift CLI (oc
) binary on macOS by using the following procedure.
Procedure
- Navigate to the Infrastructure Provider page on the Red Hat OpenShift Cluster Manager site.
- Select your infrastructure provider, and, if applicable, your installation type.
- In the Command line interface section, select MacOS from the drop-down menu and click Download command-line tools.
- Unpack and unzip the archive.
Move the
oc
binary to a directory on your PATH.To check your
PATH
, open a terminal and execute the following command:$ echo $PATH
After you install the CLI, it is available using the oc
command:
$ oc <command>
1.1.8. Manually creating the installation configuration file
For installations of OpenShift Container Platform that use user-provisioned infrastructure, you manually generate your installation configuration file.
Prerequisites
- Obtain the OpenShift Container Platform installation program and the access token for your cluster.
Procedure
Create an installation directory to store your required installation assets in:
$ mkdir <installation_directory>
重要You must create a directory. Some installation assets, like bootstrap X.509 certificates have short expiration intervals, so you must not reuse an installation directory. If you want to reuse individual files from another cluster installation, you can copy them into your directory. However, the file names for the installation assets might change between releases. Use caution when copying installation files from an earlier OpenShift Container Platform version.
Customize the following
install-config.yaml
file template and save it in the<installation_directory>
.注意You must name this configuration file
install-config.yaml
.Back up the
install-config.yaml
file so that you can use it to install multiple clusters.重要The
install-config.yaml
file is consumed during the next step of the installation process. You must back it up now.
1.1.8.1. Sample install-config.yaml
file for bare metal
1.1.8.2. Sample install-config.yaml
file for IBM Z
You can customize the install-config.yaml
file to specify more details about your OpenShift Container Platform cluster’s platform or modify the values of the required parameters.
apiVersion: v1 baseDomain: example.com 1 compute: 2 - hyperthreading: Enabled 3 name: worker replicas: 0 4 controlPlane: 5 hyperthreading: Enabled 6 name: master replicas: 3 7 metadata: name: test 8 networking: clusterNetwork: - cidr: 10.128.0.0/14 9 hostPrefix: 23 10 networkType: OpenShiftSDN serviceNetwork: 11 - 172.30.0.0/16 platform: none: {} 12 fips: false 13 pullSecret: '{"auths": ...}' 14 sshKey: 'ssh-ed25519 AAAA...' 15
- 1
- The base domain of the cluster. All DNS records must be sub-domains of this base and include the cluster name.
- 2 5
- The
controlPlane
section is a single mapping, but thecompute
section is a sequence of mappings. To meet the requirements of the different data structures, the first line of thecompute
section must begin with a hyphen,-
, and the first line of thecontrolPlane
section must not. Although both sections currently define a single machine pool, it is possible that future versions of OpenShift Container Platform will support defining multiple compute pools during installation. Only one control plane pool is used. - 3 6
- Whether to enable or disable simultaneous multithreading (SMT), or
hyperthreading
. By default, SMT is enabled to increase the performance of your machines' cores. You can disable it by setting the parameter value toDisabled
. If you disable SMT, you must disable it in all cluster machines; this includes both control plane and compute machines.注意Simultaneous multithreading (SMT) is enabled by default. If SMT is not enabled in your BIOS settings, the
hyperthreading
parameter has no effect.重要If you disable
hyperthreading
, whether in the BIOS or in theinstall-config.yaml
, ensure that your capacity planning accounts for the dramatically decreased machine performance. - 4
- You must set the value of the
replicas
parameter to0
. This parameter controls the number of workers that the cluster creates and manages for you, which are functions that the cluster does not perform when you use user-provisioned infrastructure. You must manually deploy worker machines for the cluster to use before you finish installing OpenShift Container Platform. - 7
- The number of control plane machines that you add to the cluster. Because the cluster uses this values as the number of etcd endpoints in the cluster, the value must match the number of control plane machines that you deploy.
- 8
- The cluster name that you specified in your DNS records.
- 9
- A block of IP addresses from which pod IP addresses are allocated. This block must not overlap with existing physical networks. These IP addresses are used for the pod network. If you need to access the pods from an external network, you must configure load balancers and routers to manage the traffic.
- 10
- The subnet prefix length to assign to each individual node. For example, if
hostPrefix
is set to23
, then each node is assigned a/23
subnet out of the givencidr
, which allows for 510 (2^(32 - 23) - 2) pod IPs addresses. If you are required to provide access to nodes from an external network, configure load balancers and routers to manage the traffic. - 11
- The IP address pool to use for service IP addresses. You can enter only one IP address pool. If you need to access the services from an external network, configure load balancers and routers to manage the traffic.
- 12
- You must set the platform to
none
. You cannot provide additional platform configuration variables for bare metal IBM Z infrastructure. - 13
- Whether to enable or disable FIPS mode. By default, FIPS mode is not enabled. If FIPS mode is enabled, the Red Hat Enterprise Linux CoreOS (RHCOS) machines that OpenShift Container Platform runs on bypass the default Kubernetes cryptography suite and use the cryptography modules that are provided with RHCOS instead.
- 14
- The pull secret that you obtained from the Pull Secret page on the Red Hat OpenShift Cluster Manager site. This pull secret allows you to authenticate with the services that are provided by the included authorities, including Quay.io, which serves the container images for OpenShift Container Platform components.
- 15
- The public portion of the default SSH key for the
core
user in Red Hat Enterprise Linux CoreOS (RHCOS).注意For production OpenShift Container Platform clusters on which you want to perform installation debugging or disaster recovery, specify an SSH key that your
ssh-agent
process uses.
1.1.9. Creating the Kubernetes manifest and Ignition config files
Because you must modify some cluster definition files and manually start the cluster machines, you must generate the Kubernetes manifest and Ignition config files that the cluster needs to make its machines.
The Ignition config files that the installation program generates contain certificates that expire after 24 hours, which are then renewed at that time. If the cluster is shut down before renewing the certificates and the cluster is later restarted after the 24 hours have elapsed, the cluster automatically recovers the expired certificates. The exception is that you must manually approve the pending node-bootstrapper
certificate signing requests (CSRs) to recover kubelet certificates. See the documentation for Recovering from expired control plane certificates for more information.
Prerequisites
- Obtain the OpenShift Container Platform installation program.
-
Create the
install-config.yaml
installation configuration file.
Procedure
Generate the Kubernetes manifests for the cluster:
$ ./openshift-install create manifests --dir=<installation_directory> 1
Example output
INFO Consuming Install Config from target directory WARNING Making control-plane schedulable by setting MastersSchedulable to true for Scheduler cluster settings
- 1
- For
<installation_directory>
, specify the installation directory that contains theinstall-config.yaml
file you created.
Because you create your own compute machines later in the installation process, you can safely ignore this warning.
Modify the
<installation_directory>/manifests/cluster-scheduler-02-config.yml
Kubernetes manifest file to prevent pods from being scheduled on the control plane machines:-
Open the
<installation_directory>/manifests/cluster-scheduler-02-config.yml
file. -
Locate the
mastersSchedulable
parameter and set its value toFalse
. - Save and exit the file.
-
Open the
Obtain the Ignition config files:
$ ./openshift-install create ignition-configs --dir=<installation_directory> 1
- 1
- For
<installation_directory>
, specify the same installation directory.
The following files are generated in the directory:
. ├── auth │ ├── kubeadmin-password │ └── kubeconfig ├── bootstrap.ign ├── master.ign ├── metadata.json └── worker.ign
1.1.10. Creating Red Hat Enterprise Linux CoreOS (RHCOS) machines
Before you install a cluster on IBM Z infrastructure that you provision, you must install RHCOS on z/VM guest virtual machines for the cluster to use. Complete the following steps to create the machines.
Prerequisites
- An FTP server running on your provisioning machine that is accessible to the machines you create.
Procedure
- Log in to Linux on your provisioning machine.
Download the Red Hat Enterprise Linux CoreOS (RHCOS) installation files from the RHCOS image mirror.
重要The RHCOS images might not change with every release of OpenShift Container Platform. You must download images with the highest version that is less than or equal to the OpenShift Container Platform version that you install. Use the image versions that match your OpenShift Container Platform version if they are available.
Download the following files:
-
The initramfs:
rhcos-<version>-installer-initramfs.img
-
The kernel:
rhcos-<version>-installer-kernel
The operating system image for the disk on which you want to install RHCOS. This type can differ by virtual machine:
rhcos-<version>-s390x-dasd.s390x.raw.gz
for DASDrhcos-<version>-s390x-metal.s390x.raw.gz
for FCP
-
The initramfs:
Create parameter files. The following parameters are specific for a particular virtual machine:
-
For
coreos.inst.install_dev=
, specifydasda
for a DASD installation, orsda
for FCP. Note that FCP requireszfcp.allow_lun_scan=0
. -
For
rd.dasd=
, specifys the DASD where RHCOS is to be installed. -
rd.zfcp=<adapter>,<wwpn>,<lun>
specifies the FCP disk to install RHCOS on. For
ip=
, specify the following seven entries:- The IP address for the machine.
- An empty string.
- The gateway.
- The netmask.
-
The machine host and domain name in the form
hostname.domainname
. Omit this value to let RHCOS decide set it. - The network interface name. Omit this value to let RHCOS decide set it.
- If you use static IP addresses, an empty string.
-
For
coreos.inst.ignition_url=
, specify the Ignition file for the machine role. Usebootstrap.ign
,master.ign
, orworker.ign
. All other parameters can stay as they are.
Example parameter file,
bootstrap-0.parm
, for the bootstrap machine:rd.neednet=1 coreos.inst=yes coreos.inst.install_dev=dasda coreos.inst.image_url=ftp:// cl1.provide.example.com:8080/assets/rhcos-43.80.20200430.0-s390x-dasd.390x.raw.gz coreos.inst.ignition_url=ftp://cl1.provide.example.com:8080/ignition-bootstrap-0 ip=172.18.78.2::172.18.78.1:255.255.255.0:::none nameserver=172.18.78.1 rd.znet=qeth,0.0.bdf0,0.0.bdf1,0.0.bdf2,layer2=1,portno=0 zfcp.allow_lun_scan=0 cio_ignore=all, !condev rd.dasd=0.0.3490
-
For
- Transfer the initramfs, kernel, parameter files, and RHCOS images to z/VM, for example with FTP. For details about how to transfer the files with FTP and boot from the virtual reader, see Installing under Z/VM.
Punch the files to the virtual reader of the z/VM guest virtual machine that is to become your bootstrap node.
See PUNCH in the IBM Knowledge Center.
提示You can use the CP PUNCH command or, if you use Linux, the vmur command to transfer files between two z/VM guest virtual machines.
- Log in to CMS on the bootstrap machine.
IPL the bootstrap machine from the reader:
$ ipl c
See IPL in the IBM Knowledge Center.
- Repeat this procedure for the other machines in the cluster.
1.1.11. Creating the cluster
To create the OpenShift Container Platform cluster, you wait for the bootstrap process to complete on the machines that you provisioned by using the Ignition config files that you generated with the installation program.
Prerequisites
- Create the required infrastructure for the cluster.
- You obtained the installation program and generated the Ignition config files for your cluster.
- You used the Ignition config files to create RHCOS machines for your cluster.
- Your machines have direct Internet access or have an HTTP or HTTPS proxy available.
Procedure
Monitor the bootstrap process:
$ ./openshift-install --dir=<installation_directory> wait-for bootstrap-complete \ 1 --log-level=info 2
Example output
INFO Waiting up to 30m0s for the Kubernetes API at https://api.test.example.com:6443... INFO API v1.18.3 up INFO Waiting up to 30m0s for bootstrapping to complete... INFO It is now safe to remove the bootstrap resources
The command succeeds when the Kubernetes API server signals that it has been bootstrapped on the control plane machines.
After bootstrap process is complete, remove the bootstrap machine from the load balancer.
重要You must remove the bootstrap machine from the load balancer at this point. You can also remove or reformat the machine itself.
1.1.12. Logging in to the cluster
You can log in to your cluster as a default system user by exporting the cluster kubeconfig
file. The kubeconfig
file contains information about the cluster that is used by the CLI to connect a client to the correct cluster and API server. The file is specific to a cluster and is created during OpenShift Container Platform installation.
Prerequisites
- Deploy an OpenShift Container Platform cluster.
-
Install the
oc
CLI.
Procedure
Export the
kubeadmin
credentials:$ export KUBECONFIG=<installation_directory>/auth/kubeconfig 1
- 1
- For
<installation_directory>
, specify the path to the directory that you stored the installation files in.
Verify you can run
oc
commands successfully using the exported configuration:$ oc whoami
Example output
system:admin
1.1.13. Approving the certificate signing requests for your machines
When you add machines to a cluster, two pending certificate signing requests (CSRs) are generated for each machine that you added. You must confirm that these CSRs are approved or, if necessary, approve them yourself. The client requests must be approved first, followed by the server requests.
Prerequisites
- You added machines to your cluster.
Procedure
Confirm that the cluster recognizes the machines:
$ oc get nodes
Example output
NAME STATUS ROLES AGE VERSION master-0 Ready master 63m v1.18.3 master-1 Ready master 63m v1.18.3 master-2 Ready master 64m v1.18.3 worker-0 NotReady worker 76s v1.18.3 worker-1 NotReady worker 70s v1.18.3
The output lists all of the machines that you created.
Review the pending CSRs and ensure that you see the client requests with the
Pending
orApproved
status for each machine that you added to the cluster:$ oc get csr
Example output
NAME AGE REQUESTOR CONDITION csr-mddf5 20m system:node:master-01.example.com Approved,Issued csr-z5rln 16m system:node:worker-21.example.com Approved,Issued
If the CSRs were not approved, after all of the pending CSRs for the machines you added are in
Pending
status, approve the CSRs for your cluster machines:注意Because the CSRs rotate automatically, approve your CSRs within an hour of adding the machines to the cluster. If you do not approve them within an hour, the certificates will rotate, and more than two certificates will be present for each node. You must approve all of these certificates. Once the client CSR is approved, the Kubelet creates a secondary CSR for the serving certificate, which requires manual approval. Then, subsequent serving certificate renewal requests are automatically approved by the
machine-approver
if the Kubelet requests a new certificate with identical parameters.To approve them individually, run the following command for each valid CSR:
$ oc adm certificate approve <csr_name> 1
- 1
<csr_name>
is the name of a CSR from the list of current CSRs.
To approve all pending CSRs, run the following command:
$ oc get csr -o go-template='{{range .items}}{{if not .status}}{{.metadata.name}}{{"\n"}}{{end}}{{end}}' | xargs --no-run-if-empty oc adm certificate approve
Now that your client requests are approved, you must review the server requests for each machine that you added to the cluster:
$ oc get csr
Example output
NAME AGE REQUESTOR CONDITION csr-bfd72 5m26s system:node:ip-10-0-50-126.us-east-2.compute.internal Pending csr-c57lv 5m26s system:node:ip-10-0-95-157.us-east-2.compute.internal Pending ...
If the remaining CSRs are not approved, and are in the
Pending
status, approve the CSRs for your cluster machines:To approve them individually, run the following command for each valid CSR:
$ oc adm certificate approve <csr_name> 1
- 1
<csr_name>
is the name of a CSR from the list of current CSRs.
To approve all pending CSRs, run the following command:
$ oc get csr -o go-template='{{range .items}}{{if not .status}}{{.metadata.name}}{{"\n"}}{{end}}{{end}}' | xargs oc adm certificate approve
After all client and server CSRs have been approved, the machines have the
Ready
status. Verify this by running the following command:$ oc get nodes
Example output
NAME STATUS ROLES AGE VERSION master-0 Ready master 73m v1.20.0 master-1 Ready master 73m v1.20.0 master-2 Ready master 74m v1.20.0 worker-0 Ready worker 11m v1.20.0 worker-1 Ready worker 11m v1.20.0
注意It can take a few minutes after approval of the server CSRs for the machines to transition to the
Ready
status.
Additional information
- For more information on CSRs, see Certificate Signing Requests.
1.1.14. Initial Operator configuration
After the control plane initializes, you must immediately configure some Operators so that they all become available.
Prerequisites
- Your control plane has initialized.
Procedure
Watch the cluster components come online:
$ watch -n5 oc get clusteroperators
Example output
NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE authentication 4.5.4 True False False 69s cloud-credential 4.5.4 True False False 12m cluster-autoscaler 4.5.4 True False False 11m console 4.5.4 True False False 46s dns 4.5.4 True False False 11m image-registry 4.5.4 True False False 5m26s ingress 4.5.4 True False False 5m36s kube-apiserver 4.5.4 True False False 8m53s kube-controller-manager 4.5.4 True False False 7m24s kube-scheduler 4.5.4 True False False 12m machine-api 4.5.4 True False False 12m machine-config 4.5.4 True False False 7m36s marketplace 4.5.4 True False False 7m54m monitoring 4.5.4 True False False 7h54s network 4.5.4 True False False 5m9s node-tuning 4.5.4 True False False 11m openshift-apiserver 4.5.4 True False False 11m openshift-controller-manager 4.5.4 True False False 5m943s openshift-samples 4.5.4 True False False 3m55s operator-lifecycle-manager 4.5.4 True False False 11m operator-lifecycle-manager-catalog 4.5.4 True False False 11m service-ca 4.5.4 True False False 11m service-catalog-apiserver 4.5.4 True False False 5m26s service-catalog-controller-manager 4.5.4 True False False 5m25s storage 4.5.4 True False False 5m30s
- Configure the Operators that are not available.
1.1.14.1. Image registry storage configuration
The Image Registry Operator is not initially available for platforms that do not provide default storage. After installation, you must configure your registry to use storage so that the Registry Operator is made available.
Instructions are shown for configuring a persistent volume, which is required for production clusters. Where applicable, instructions are shown for configuring an empty directory as the storage location, which is available for only non-production clusters.
Additional instructions are provided for allowing the image registry to use block storage types by using the Recreate
rollout strategy during upgrades.
1.1.14.1.1. Configuring registry storage for bare metal
As a cluster administrator, following installation you must configure your registry to use storage.
Prerequisites
- Cluster administrator permissions.
- A cluster on bare metal.
Persistent storage provisioned for your cluster, such as Red Hat OpenShift Container Storage.
重要OpenShift Container Platform supports
ReadWriteOnce
access for image registry storage when you have only one replica. To deploy an image registry that supports high availability with two or more replicas,ReadWriteMany
access is required.- Must have 100Gi capacity.
Procedure
To configure your registry to use storage, change the
spec.storage.pvc
in theconfigs.imageregistry/cluster
resource.注意When using shared storage, review your security settings to prevent outside access.
Verify that you do not have a registry pod:
$ oc get pod -n openshift-image-registry
注意If the storage type is
emptyDIR
, the replica number cannot be greater than1
.Check the registry configuration:
$ oc edit configs.imageregistry.operator.openshift.io
Example output
storage: pvc: claim:
Leave the
claim
field blank to allow the automatic creation of animage-registry-storage
PVC.Check the
clusteroperator
status:$ oc get clusteroperator image-registry
1.1.14.1.2. Configuring storage for the image registry in non-production clusters
You must configure storage for the Image Registry Operator. For non-production clusters, you can set the image registry to an empty directory. If you do so, all images are lost if you restart the registry.
Procedure
To set the image registry storage to an empty directory:
$ oc patch configs.imageregistry.operator.openshift.io cluster --type merge --patch '{"spec":{"storage":{"emptyDir":{}}}}'
警告Configure this option for only non-production clusters.
If you run this command before the Image Registry Operator initializes its components, the
oc patch
command fails with the following error:Error from server (NotFound): configs.imageregistry.operator.openshift.io "cluster" not found
Wait a few minutes and run the command again.
Ensure that your registry is set to managed to enable building and pushing of images.
Run:
$ oc edit configs.imageregistry/cluster
Then, change the line
managementState: Removed
to
managementState: Managed
1.1.15. Completing installation on user-provisioned infrastructure
After you complete the Operator configuration, you can finish installing the cluster on infrastructure that you provide.
Prerequisites
- Your control plane has initialized.
- You have completed the initial Operator configuration.
Procedure
Confirm that all the cluster components are online with the following command:
$ watch -n5 oc get clusteroperators
Example output
NAME VERSION AVAILABLE PROGRESSING DEGRADED SINCE authentication 4.5.4 True False False 7m56s cloud-credential 4.5.4 True False False 31m cluster-autoscaler 4.5.4 True False False 16m console 4.5.4 True False False 10m csi-snapshot-controller 4.5.4 True False False 16m dns 4.5.4 True False False 22m etcd 4.5.4 False False False 25s image-registry 4.5.4 True False False 16m ingress 4.5.4 True False False 16m insights 4.5.4 True False False 17m kube-apiserver 4.5.4 True False False 19m kube-controller-manager 4.5.4 True False False 20m kube-scheduler 4.5.4 True False False 20m kube-storage-version-migrator 4.5.4 True False False 16m machine-api 4.5.4 True False False 22m machine-config 4.5.4 True False False 22m marketplace 4.5.4 True False False 16m monitoring 4.5.4 True False False 10m network 4.5.4 True False False 23m node-tuning 4.5.4 True False False 23m openshift-apiserver 4.5.4 True False False 17m openshift-controller-manager 4.5.4 True False False 15m openshift-samples 4.5.4 True False False 16m operator-lifecycle-manager 4.5.4 True False False 22m operator-lifecycle-manager-catalog 4.5.4 True False False 22m operator-lifecycle-manager-packageserver 4.5.4 True False False 18m service-ca 4.5.4 True False False 23m service-catalog-apiserver 4.5.4 True False False 23m service-catalog-controller-manager 4.5.4 True False False 23m storage 4.5.4 True False False 17m
Alternatively, the following command notifies you when all of the clusters are available. It also retrieves and displays credentials:
$ ./openshift-install --dir=<installation_directory> wait-for install-complete 1
- 1
- For
<installation_directory>
, specify the path to the directory that you stored the installation files in.
Example output
INFO Waiting up to 30m0s for the cluster to initialize...
The command succeeds when the Cluster Version Operator finishes deploying the OpenShift Container Platform cluster from Kubernetes API server.
重要The Ignition config files that the installation program generates contain certificates that expire after 24 hours, which are then renewed at that time. If the cluster is shut down before renewing the certificates and the cluster is later restarted after the 24 hours have elapsed, the cluster automatically recovers the expired certificates. The exception is that you must manually approve the pending
node-bootstrapper
certificate signing requests (CSRs) to recover kubelet certificates. See the documentation for Recovering from expired control plane certificates for more information.Confirm that the Kubernetes API server is communicating with the pods.
To view a list of all pods, use the following command:
$ oc get pods --all-namespaces
Example output
NAMESPACE NAME READY STATUS RESTARTS AGE openshift-apiserver-operator openshift-apiserver-operator-85cb746d55-zqhs8 1/1 Running 1 9m openshift-apiserver apiserver-67b9g 1/1 Running 0 3m openshift-apiserver apiserver-ljcmx 1/1 Running 0 1m openshift-apiserver apiserver-z25h4 1/1 Running 0 2m openshift-authentication-operator authentication-operator-69d5d8bf84-vh2n8 1/1 Running 0 5m ...
View the logs for a pod that is listed in the output of the previous command by using the following command:
$ oc logs <pod_name> -n <namespace> 1
- 1
- Specify the pod name and namespace, as shown in the output of the previous command.
If the pod logs display, the Kubernetes API server can communicate with the cluster machines.
1.1.16. Collecting debugging information
You can gather debugging information that might help you to troubleshoot and debug certain issues with an OpenShift Container Platform installation on IBM Z.
Prerequisites
-
The
oc
CLI tool installed.
Procedure
Log in to the cluster:
$ oc login
On the node you want to gather hardware information about, start a debugging container:
$ oc debug node/<nodename>
Change to the /host file system and start
toolbox
:$ chroot /host $ toolbox
Collect the
dbginfo
data:$ dbginfo.sh
-
You can then retrieve the data, for example, using
scp
.
1.1.17. Additional resources
1.1.18. Next steps
- Customize your cluster.
- If necessary, you can opt out of remote health reporting.