Installing a cluster on VMC with customizations

In OKD version 4.12, you can install a cluster on your VMware vSphere instance using installer-provisioned infrastructure by deploying it to VMware Cloud (VMC) on AWS.

Once you configure your VMC environment for OKD deployment, you use the OKD installation program from the bastion management host, co-located in the VMC environment. The installation program and control plane automates the process of deploying and managing the resources needed for the OKD cluster.

To customize the OKD installation, you modify parameters in the install-config.yaml file before you install the cluster.

Setting up VMC for vSphere

You can install OKD on VMware Cloud (VMC) on AWS hosted vSphere clusters to enable applications to be deployed and managed both on-premise and off-premise, across the hybrid cloud.

You must configure several options in your VMC environment prior to installing OKD on VMware vSphere. Ensure your VMC environment has the following prerequisites:

• Create a non-exclusive, DHCP-enabled, NSX-T network segment and subnet. Other virtual machines (VMs) can be hosted on the subnet, but at least eight IP addresses must be available for the OKD deployment.

• Allocate two IP addresses, outside the DHCP range, and configure them with reverse DNS records.

  • A DNS record for api.<cluster_name>.<base_domain> pointing to the allocated IP address.

  • A DNS record for *.apps.<cluster_name>.<base_domain> pointing to the allocated IP address.

• Configure the following firewall rules:

  • An ANY:ANY firewall rule between the OKD compute network and the internet. This is used by nodes and applications to download container images.

  • An ANY:ANY firewall rule between the installation host and the software-defined data center (SDDC) management network on port 443. This allows you to upload the Fedora CoreOS (FCOS) OVA during deployment.

  • An HTTPS firewall rule between the OKD compute network and vCenter. This connection allows OKD to communicate with vCenter for provisioning and managing nodes, persistent volume claims (PVCs), and other resources.

• You must have the following information to deploy OKD:

  • The OKD cluster name, such as vmc-prod-1.

  • The base DNS name, such as companyname.com.

  • If not using the default, the pod network CIDR and services network CIDR must be identified, which are set by default to 10.128.0.0/14 and 172.30.0.0/16, respectively. These CIDRs are used for pod-to-pod and pod-to-service communication and are not accessible externally; however, they must not overlap with existing subnets in your organization.

  • The following vCenter information:

    • vCenter hostname, username, and password

    • Datacenter name, such as SDDC-Datacenter

    • Cluster name, such as Cluster-1

    • Network name

    • Datastore name, such as WorkloadDatastore

      It is recommended to move your vSphere cluster to the VMC Compute-ResourcePool resource pool after your cluster installation is finished.

• A Linux-based host deployed to VMC as a bastion.

  • The bastion host can be Fedora or any another Linux-based host; it must have internet connectivity and the ability to upload an OVA to the ESXi hosts.

  • Download and install the OpenShift CLI tools to the bastion host.

    • The openshift-install installation program

    • The OpenShift CLI (oc) tool

VMC Sizer tool

VMware Cloud on AWS is built on top of AWS bare metal infrastructure; this is the same bare metal infrastructure which runs AWS native services. When a VMware cloud on AWS software-defined data center (SDDC) is deployed, you consume these physical server nodes and run the VMware ESXi hypervisor in a single tenant fashion. This means the physical infrastructure is not accessible to anyone else using VMC. It is important to consider how many physical hosts you will need to host your virtual infrastructure.

To determine this, VMware provides the VMC on AWS Sizer. With this tool, you can define the resources you intend to host on VMC:

• Types of workloads

• Total number of virtual machines

• Specification information such as:

  • Storage requirements

  • vCPUs

  • vRAM

  • Overcommit ratios

With these details, the sizer tool can generate a report, based on VMware best practices, and recommend your cluster configuration and the number of hosts you will need.

vSphere prerequisites

• You reviewed details about the OKD installation and update processes.

• You read the documentation on selecting a cluster installation method and preparing it for users.

• You provisioned block registry storage. For more information on persistent storage, see Understanding persistent storage.

• If you use a firewall, you configured it to allow the sites that your cluster requires access to.

  Be sure to also review this site list if you are configuring a proxy.

VMware vSphere infrastructure requirements

You must install the OKD cluster on a VMware vSphere version 7 instance that meets the requirements for the components that you use.

Network connectivity requirements

You must configure the network connectivity between machines to allow OKD cluster components to communicate.

Review the following details about the required network ports.

VMware vSphere CSI Driver Operator requirements

To install the CSI Driver Operator, the following requirements must be met:

• VMware vSphere version 7.0.2 or later

• vCenter 7.0.2 or later

• Virtual machines of hardware version 15 or later

• No third-party CSI driver already installed in the cluster

If a third-party CSI driver is present in the cluster, OKD does not overwrite it. The presence of a third-party CSI driver prevents OKD from upgrading to OKD 4.13 or later.

Additional resources

• To remove a third-party CSI driver, see Removing a third-party vSphere CSI Driver.

• To update the hardware version for your vSphere nodes, see Updating hardware on nodes running in vSphere.

vCenter requirements

Before you install an OKD cluster on your vCenter that uses infrastructure that the installer provisions, you must prepare your environment.

Required vCenter account privileges

To install an OKD cluster in a vCenter, the installation program requires access to an account with privileges to read and create the required resources. Using an account that has global administrative privileges is the simplest way to access all of the necessary permissions.

If you cannot use an account with global administrative privileges, you must create roles to grant the privileges necessary for OKD cluster installation. While most of the privileges are always required, some are required only if you plan for the installation program to provision a folder to contain the OKD cluster on your vCenter instance, which is the default behavior. You must create or amend vSphere roles for the specified objects to grant the required privileges.

An additional role is required if the installation program is to create a vSphere virtual machine folder.

Roles and privileges required for installation in vSphere API

Roles and privileges required for installation in vCenter graphical user interface (GUI)

Additionally, the user requires some ReadOnly permissions, and some of the roles require permission to propogate the permissions to child objects. These settings vary depending on whether or not you install the cluster into an existing folder.

Required permissions and propagation settings

For more information about creating an account with only the required privileges, see vSphere Permissions and User Management Tasks in the vSphere documentation.

Using OKD with vMotion

If you intend on using vMotion in your vSphere environment, consider the following before installing a OKD cluster.

• OKD generally supports compute-only vMotion. Using Storage vMotion can cause issues and is not supported.

  To help ensure the uptime of your compute and control plane nodes, it is recommended that you follow the VMware best practices for vMotion. It is also recommended to use VMware anti-affinity rules to improve the availability of OKD during maintenance or hardware issues.

  For more information about vMotion and anti-affinity rules, see the VMware vSphere documentation for vMotion networking requirements and VM anti-affinity rules.

• If you are using vSphere volumes in your pods, migrating a VM across datastores either manually or through Storage vMotion causes, invalid references within OKD persistent volume (PV) objects. These references prevent affected pods from starting up and can result in data loss.

• Similarly, OKD does not support selective migration of VMDKs across datastores, using datastore clusters for VM provisioning or for dynamic or static provisioning of PVs, or using a datastore that is part of a datastore cluster for dynamic or static provisioning of PVs.

Cluster resources

When you deploy an OKD cluster that uses installer-provisioned infrastructure, the installation program must be able to create several resources in your vCenter instance.

A standard OKD installation creates the following vCenter resources:

• 1 Folder

• 1 Tag category

• 1 Tag

• Virtual machines:

  • 1 template

  • 1 temporary bootstrap node

  • 3 control plane nodes

  • 3 compute machines

Although these resources use 856 GB of storage, the bootstrap node is destroyed during the cluster installation process. A minimum of 800 GB of storage is required to use a standard cluster.

If you deploy more compute machines, the OKD cluster will use more storage.

Cluster limits

Available resources vary between clusters. The number of possible clusters within a vCenter is limited primarily by available storage space and any limitations on the number of required resources. Be sure to consider both limitations to the vCenter resources that the cluster creates and the resources that you require to deploy a cluster, such as IP addresses and networks.

Networking requirements

You must use DHCP for the network and ensure that the DHCP server is configured to provide persistent IP addresses to the cluster machines. All nodes must be in the same VLAN. You cannot scale the cluster using a second VLAN as a Day 2 operation. Additionally, you must create the following networking resources before you install the OKD cluster:

Required IP Addresses

An installer-provisioned vSphere installation requires two static IP addresses:

• The API address is used to access the cluster API.

• The Ingress address is used for cluster ingress traffic.

You must provide these IP addresses to the installation program when you install the OKD cluster.

DNS records

You must create DNS records for two static IP addresses in the appropriate DNS server for the vCenter instance that hosts your OKD cluster. In each record, <cluster_name> is the cluster name and <base_domain> is the cluster base domain that you specify when you install the cluster. A complete DNS record takes the form: <component>.<cluster_name>.<base_domain>..

Generating a key pair for cluster node SSH access

During an OKD installation, you can provide an SSH public key to the installation program. The key is passed to the Fedora CoreOS (FCOS) nodes through their Ignition config files and is used to authenticate SSH access to the nodes. The key is added to the ~/.ssh/authorized_keys list for the core user on each node, which enables password-less authentication.

After the key is passed to the nodes, you can use the key pair to SSH in to the FCOS nodes as the user core. To access the nodes through SSH, the private key identity must be managed by SSH for your local user.

If you want to SSH in to your cluster nodes to perform installation debugging or disaster recovery, you must provide the SSH public key during the installation process. The ./openshift-install gather command also requires the SSH public key to be in place on the cluster nodes.

Procedure

1. If you do not have an existing SSH key pair on your local machine to use for authentication onto your cluster nodes, 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_ed25519, of the new SSH key. If you have an existing key pair, ensure your public key is in the your ~/.ssh directory.

   If you plan to install an OKD cluster that uses FIPS Validated / Modules in Process cryptographic libraries on the x86_64 architecture, do not create a key that uses the ed25519 algorithm. Instead, create a key that uses the rsa or ecdsa algorithm.

2. View the public SSH key:

   $ cat <path>/<file_name>.pub

   For example, run the following to view the ~/.ssh/id_ed25519.pub public key:

   $ cat ~/.ssh/id_ed25519.pub

3. Add the SSH private key identity to the SSH agent for your local user, if it has not already been added. SSH agent management of the key is required for password-less SSH authentication onto your cluster nodes, or if you want to use the ./openshift-install gather command.

   On some distributions, default SSH private key identities such as ~/.ssh/id_rsa and ~/.ssh/id_dsa are managed automatically.

   1. If the ssh-agent process is not already running for your local user, start it as a background task:

      $ eval "$(ssh-agent -s)"

      Example output

      Agent pid 31874

      If your cluster is in FIPS mode, only use FIPS-compliant algorithms to generate the SSH key. The key must be either RSA or ECDSA.

4. Add your SSH private key to the ssh-agent:

   $ ssh-add <path>/<file_name> (1)

   1	Specify the path and file name for your SSH private key, such as ~/.ssh/id_ed25519

   Example output

   Identity added: /home/<you>/<path>/<file_name> (<computer_name>)

Next steps

• When you install OKD, provide the SSH public key to the installation program.

Obtaining the installation program

Before you install OKD, download the installation file on the host you are using for installation.

Prerequisites

• You have a computer that runs Linux or macOS, with 500 MB of local disk space.

Procedure

1. Download installer from https://github.com/openshift/okd/releases

   The installation program creates several files on the computer that you use to install your cluster. You must keep the installation program and the files that the installation program creates after you finish installing the cluster. Both files are required to delete the cluster.

   Deleting the files created by the installation program does not remove your cluster, even if the cluster failed during installation. To remove your cluster, complete the OKD uninstallation procedures for your specific cloud provider.

2. Extract the installation program. For example, on a computer that uses a Linux operating system, run the following command:

   $ tar -xvf openshift-install-linux.tar.gz

3. Download your installation pull secret from the Red Hat OpenShift Cluster Manager. 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 OKD components.

   Using a pull secret from the Red Hat OpenShift Cluster Manager is not required. You can use a pull secret for another private registry. Or, if you do not need the cluster to pull images from a private registry, you can use {"auths":{"fake":{"auth":"aWQ6cGFzcwo="}}} as the pull secret when prompted during the installation.

   If you do not use the pull secret from the Red Hat OpenShift Cluster Manager:

   • Red Hat Operators are not available.

   • The Telemetry and Insights operators do not send data to Red Hat.

   • Content from the Red Hat Container Catalog registry, such as image streams and Operators, are not available.

Adding vCenter root CA certificates to your system trust

Because the installation program requires access to your vCenter’s API, you must add your vCenter’s trusted root CA certificates to your system trust before you install an OKD cluster.

Procedure

1. From the vCenter home page, download the vCenter’s root CA certificates. Click Download trusted root CA certificates in the vSphere Web Services SDK section. The <vCenter>/certs/download.zip file downloads.

2. Extract the compressed file that contains the vCenter root CA certificates. The contents of the compressed file resemble the following file structure:

   certs
   ├── lin
   │   ├── 108f4d17.0
   │   ├── 108f4d17.r1
   │   ├── 7e757f6a.0
   │   ├── 8e4f8471.0
   │   └── 8e4f8471.r0
   ├── mac
   │   ├── 108f4d17.0
   │   ├── 108f4d17.r1
   │   ├── 7e757f6a.0
   │   ├── 8e4f8471.0
   │   └── 8e4f8471.r0
   └── win
       ├── 108f4d17.0.crt
       ├── 108f4d17.r1.crl
       ├── 7e757f6a.0.crt
       ├── 8e4f8471.0.crt
       └── 8e4f8471.r0.crl
   3 directories, 15 files

3. Add the files for your operating system to the system trust. For example, on a Fedora operating system, run the following command:

   # cp certs/lin/* /etc/pki/ca-trust/source/anchors

4. Update your system trust. For example, on a Fedora operating system, run the following command:

   # update-ca-trust extract

Creating the installation configuration file

You can customize the OKD cluster you install on VMware vSphere.

Prerequisites

• Obtain the OKD installation program and the pull secret for your cluster.

• Obtain service principal permissions at the subscription level.

Procedure

1. Create the install-config.yaml file.

   1. Change to the directory that contains the installation program and run the following command:

      $ ./openshift-install create install-config --dir <installation_directory> (1)

      1	For <installation_directory>, specify the directory name to store the files that the installation program creates.

      When specifying the directory:

      • Verify that the directory has the execute permission. This permission is required to run Terraform binaries under the installation directory.

      • Use an empty directory. Some installation assets, such as bootstrap X.509 certificates, have short expiration intervals, therefore 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 OKD version.

   2. At the prompts, provide the configuration details for your cloud:

      1. Optional: Select an SSH key to use to access your cluster machines.

         For production OKD clusters on which you want to perform installation debugging or disaster recovery, specify an SSH key that your ssh-agent process uses.

      2. Select vsphere as the platform to target.

      3. Specify the name of your vCenter instance.

      4. Specify the user name and password for the vCenter account that has the required permissions to create the cluster.

         The installation program connects to your vCenter instance.

      5. Select the data center in your vCenter instance to connect to.

      6. Select the default vCenter datastore to use.

      7. Select the vCenter cluster to install the OKD cluster in. The installation program uses the root resource pool of the vSphere cluster as the default resource pool.

      8. Select the network in the vCenter instance that contains the virtual IP addresses and DNS records that you configured.

      9. Enter the virtual IP address that you configured for control plane API access.

      10. Enter the virtual IP address that you configured for cluster ingress.

      11. Enter the base domain. This base domain must be the same one that you used in the DNS records that you configured.

      12. Enter a descriptive name for your cluster. The cluster name you enter must match the cluster name you specified when configuring the DNS records.

      13. Paste the pull secret from the Red Hat OpenShift Cluster Manager. This field is optional.

1. Modify the install-config.yaml file. You can find more information about the available parameters in the “Installation configuration parameters” section.

2. Back up the install-config.yaml file so that you can use it to install multiple clusters.

   The install-config.yaml file is consumed during the installation process. If you want to reuse the file, you must back it up now.

Installation configuration parameters

Before you deploy an OKD cluster, you provide parameter values to describe your account on the cloud platform that hosts your cluster and optionally customize your cluster’s platform. When you create the install-config.yaml installation configuration file, you provide values for the required parameters through the command line. If you customize your cluster, you can modify the install-config.yaml file to provide more details about the platform.

Required configuration parameters

Required installation configuration parameters are described in the following table:

Network configuration parameters

You can customize your installation configuration based on the requirements of your existing network infrastructure. For example, you can expand the IP address block for the cluster network or provide different IP address blocks than the defaults.

Only IPv4 addresses are supported.

networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14
    hostPrefix: 23

networking:
  serviceNetwork:
   - 172.30.0.0/16

networking:
  machineNetwork:
  - cidr: 10.0.0.0/16

Optional configuration parameters

Optional installation configuration parameters are described in the following table:

sshKey:
  <key1>
  <key2>
  <key3>

Additional VMware vSphere configuration parameters

Additional VMware vSphere configuration parameters are described in the following table:

Optional VMware vSphere machine pool configuration parameters

Optional VMware vSphere machine pool configuration parameters are described in the following table:

Sample install-config.yaml file for an installer-provisioned VMware vSphere cluster

You can customize the install-config.yaml file to specify more details about your OKD 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: 3
  platform:
    vsphere: (4)
      cpus: 2
      coresPerSocket: 2
      memoryMB: 8192
      osDisk:
        diskSizeGB: 120
controlPlane: (2)
  hyperthreading: Enabled (3)
  name: master
  replicas: 3
  platform:
    vsphere: (4)
      cpus: 4
      coresPerSocket: 2
      memoryMB: 16384
      osDisk:
        diskSizeGB: 120
metadata:
  name: cluster (5)
platform:
  vsphere:
    vcenter: your.vcenter.server
    username: username
    password: password
    datacenter: datacenter
    defaultDatastore: datastore
    folder: folder
    resourcePool: resource_pool (6)
    diskType: thin (7)
    network: VM_Network
    cluster: vsphere_cluster_name (8)
    apiVIPs:
      - api_vip
    ingressVIPs:
      - ingress_vip
pullSecret: '{"auths": ...}'
sshKey: 'ssh-ed25519 AAAA...'

Configuring the cluster-wide proxy during installation

Production environments can deny direct access to the internet and instead have an HTTP or HTTPS proxy available. You can configure a new OKD cluster to use a proxy by configuring the proxy settings in the install-config.yaml file.

Prerequisites

• You have an existing install-config.yaml file.

• You reviewed the sites that your cluster requires access to and determined whether any of them need to bypass the proxy. By default, all cluster egress traffic is proxied, including calls to hosting cloud provider APIs. You added sites to the Proxy object’s spec.noProxy field to bypass the proxy if necessary.

  The Proxy object status.noProxy field is populated with the values of the networking.machineNetwork[].cidr, networking.clusterNetwork[].cidr, and networking.serviceNetwork[] fields from your installation configuration. For installations on Amazon Web Services (AWS), Google Cloud Platform (GCP), Microsoft Azure, and OpenStack, the Proxy object status.noProxy field is also populated with the instance metadata endpoint (169.254.169.254).

Procedure

1. Edit your install-config.yaml file and add the proxy settings. For example:

   apiVersion: v1
   baseDomain: my.domain.com
   proxy:
     httpProxy: http://<username>:<pswd>@<ip>:<port> (1)
     httpsProxy: https://<username>:<pswd>@<ip>:<port> (2)
     noProxy: example.com (3)
   additionalTrustBundle: | (4)
       -----BEGIN CERTIFICATE-----
       <MY_TRUSTED_CA_CERT>
       -----END CERTIFICATE-----
   additionalTrustBundlePolicy: <policy_to_add_additionalTrustBundle> (5)

   1	A proxy URL to use for creating HTTP connections outside the cluster. The URL scheme must be http.
   2	A proxy URL to use for creating HTTPS connections outside the cluster.
   3	A comma-separated list of destination domain names, IP addresses, or other network CIDRs to exclude from proxying. Preface a domain with . to match subdomains only. For example, .y.com matches x.y.com, but not y.com. Use * to bypass the proxy for all destinations. You must include vCenter’s IP address and the IP range that you use for its machines.
   4	If provided, the installation program generates a config map that is named user-ca-bundle in the openshift-config namespace that contains one or more additional CA certificates that are required for proxying HTTPS connections. The Cluster Network Operator then creates a trusted-ca-bundle config map that merges these contents with the Fedora CoreOS (FCOS) trust bundle, and this config map is referenced in the trustedCA field of the Proxy object. The additionalTrustBundle field is required unless the proxy’s identity certificate is signed by an authority from the FCOS trust bundle.
   5	Optional: The policy to determine the configuration of the Proxy object to reference the user-ca-bundle config map in the trustedCA field. The allowed values are Proxyonly and Always. Use Proxyonly to reference the user-ca-bundle config map only when http/https proxy is configured. Use Always to always reference the user-ca-bundle config map. The default value is Proxyonly.

   The installation program does not support the proxy readinessEndpoints field.

2. Save the file and reference it when installing OKD.

The installation program creates a cluster-wide proxy that is named cluster that uses the proxy settings in the provided install-config.yaml file. If no proxy settings are provided, a cluster Proxy object is still created, but it will have a nil spec.

Deploying the cluster

You can install OKD on a compatible cloud platform.

Prerequisites

• Configure an account with the cloud platform that hosts your cluster.

• Obtain the OKD installation program and the pull secret for your cluster.

Procedure

• Change to the directory that contains the installation program and initialize the cluster deployment:

  $ ./openshift-install create cluster --dir <installation_directory> \ (1)
      --log-level=info (2)

  1	For <installation_directory>, specify the location of your customized ./install-config.yaml file.
  2	To view different installation details, specify warn, debug, or error instead of info.

  Use the openshift-install command from the bastion hosted in the VMC environment.

  If the cloud provider account that you configured on your host does not have sufficient permissions to deploy the cluster, the installation process stops, and the missing permissions are displayed.

Verification

When the cluster deployment completes successfully:

• The terminal displays directions for accessing your cluster, including a link to the web console and credentials for the kubeadmin user.

• Credential information also outputs to <installation_directory>/.openshift_install.log.

Example output

...
INFO Install complete!
INFO To access the cluster as the system:admin user when using 'oc', run 'export KUBECONFIG=/home/myuser/install_dir/auth/kubeconfig'
INFO Access the OpenShift web-console here: https://console-openshift-console.apps.mycluster.example.com
INFO Login to the console with user: "kubeadmin", and password: "4vYBz-Ee6gm-ymBZj-Wt5AL"
INFO Time elapsed: 36m22s

Installing the OpenShift CLI by downloading the binary

You can install the OpenShift CLI (oc) to interact with OKD from a command-line interface. You can install oc on Linux, Windows, or macOS.

Installing the OpenShift CLI on Linux

You can install the OpenShift CLI (oc) binary on Linux by using the following procedure.

Procedure

1. Navigate to link:https://mirror.openshift.com/pub/openshift-v4/clients/oc/latest/ and choose the folder for your operating system and architecture.

2. Download oc.tar.gz.

3. Unpack the archive:

   $ tar xvzf <file>

4. Place the oc binary in a directory that is on your PATH.

   To check your PATH, execute the following command:

   $ echo $PATH

After you install the OpenShift CLI, it is available using the oc command:

$ oc <command>

Installing the OpenShift CLI on Windows

You can install the OpenShift CLI (oc) binary on Windows by using the following procedure.

Procedure

1. Navigate to link:https://mirror.openshift.com/pub/openshift-v4/clients/oc/latest/ and choose the folder for your operating system and architecture.

2. Download oc.zip.

3. Unzip the archive with a ZIP program.

4. Move the oc binary to a directory that is on your PATH.

   To check your PATH, open the command prompt and execute the following command:

   C:\> path

After you install the OpenShift CLI, it is available using the oc command:

C:\> oc <command>

Installing the OpenShift CLI on macOS

You can install the OpenShift CLI (oc) binary on macOS by using the following procedure.

Procedure

1. Navigate to link:https://mirror.openshift.com/pub/openshift-v4/clients/oc/latest/ and choose the folder for your operating system and architecture.

2. Download oc.tar.gz.

3. Unpack and unzip the archive.

4. 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 OpenShift CLI, it is available using the oc command:

$ oc <command>

Logging in to the cluster by using the CLI

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 OKD installation.

Prerequisites

• You deployed an OKD cluster.

• You installed the oc CLI.

Procedure

1. 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.

2. Verify you can run oc commands successfully using the exported configuration:

   $ oc whoami

   Example output

   system:admin

Creating registry storage

After you install the cluster, you must create storage for the Registry Operator.

Image registry removed during installation

On platforms that do not provide shareable object storage, the OpenShift Image Registry Operator bootstraps itself as Removed. This allows openshift-installer to complete installations on these platform types.

After installation, you must edit the Image Registry Operator configuration to switch the managementState from Removed to Managed.

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.

Configuring registry storage for VMware vSphere

As a cluster administrator, following installation you must configure your registry to use storage.

Prerequisites

• Cluster administrator permissions.

• A cluster on VMware vSphere.

• Persistent storage provisioned for your cluster, such as Red Hat OpenShift Data Foundation.

  OKD supports ReadWriteOnce access for image registry storage when you have only one replica. ReadWriteOnce access also requires that the registry uses the Recreate rollout strategy. To deploy an image registry that supports high availability with two or more replicas, ReadWriteMany access is required.

• Must have “100Gi” capacity.

Procedure

1. To configure your registry to use storage, change the spec.storage.pvc in the configs.imageregistry/cluster resource.

   When using shared storage, review your security settings to prevent outside access.

2. Verify that you do not have a registry pod:

   $ oc get pod -n openshift-image-registry -l docker-registry=default

   Example output

   No resourses found in openshift-image-registry namespace

   If you do have a registry pod in your output, you do not need to continue with this procedure.

3. Check the registry configuration:

   $ oc edit configs.imageregistry.operator.openshift.io

   Example output

   storage:
     pvc:
       claim: (1)

   1

   Leave the claim field blank to allow the automatic creation of an image-registry-storage persistent volume claim (PVC). The PVC is generated based on the default storage class. However, be aware that the default storage class might provide ReadWriteOnce (RWO) volumes, such as a RADOS Block Device (RBD), which can cause issues when replicating to more than one replica.

4. Check the clusteroperator status:

   $ oc get clusteroperator image-registry

   Example output

   NAME             VERSION                              AVAILABLE   PROGRESSING   DEGRADED   SINCE   MESSAGE
   image-registry   4.7                                  True        False         False      6h50m

Configuring block registry storage for VMware vSphere

To allow the image registry to use block storage types such as vSphere Virtual Machine Disk (VMDK) during upgrades as a cluster administrator, you can use the Recreate rollout strategy.

Procedure

1. To set the image registry storage as a block storage type, patch the registry so that it uses the Recreate rollout strategy and runs with only 1 replica:

   $ oc patch config.imageregistry.operator.openshift.io/cluster --type=merge -p '{"spec":{"rolloutStrategy":"Recreate","replicas":1}}'

2. Provision the PV for the block storage device, and create a PVC for that volume. The requested block volume uses the ReadWriteOnce (RWO) access mode.

   1. Create a pvc.yaml file with the following contents to define a VMware vSphere PersistentVolumeClaim object:

      kind: PersistentVolumeClaim
      apiVersion: v1
      metadata:
        name: image-registry-storage (1)
        namespace: openshift-image-registry (2)
      spec:
        accessModes:
        - ReadWriteOnce (3)
        resources:
          requests:
            storage: 100Gi (4)

      1	A unique name that represents the PersistentVolumeClaim object.
      2	The namespace for the PersistentVolumeClaim object, which is openshift-image-registry.
      3	The access mode of the persistent volume claim. With ReadWriteOnce, the volume can be mounted with read and write permissions by a single node.
      4	The size of the persistent volume claim.

   2. Create the PersistentVolumeClaim object from the file:

      $ oc create -f pvc.yaml -n openshift-image-registry

3. Edit the registry configuration so that it references the correct PVC:

   $ oc edit config.imageregistry.operator.openshift.io -o yaml

   Example output

   storage:
     pvc:
       claim: (1)

   1	Creating a custom PVC allows you to leave the claim field blank for the default automatic creation of an image-registry-storage PVC.

For instructions about configuring registry storage so that it references the correct PVC, see Configuring the registry for vSphere.

Backing up VMware vSphere volumes

OKD provisions new volumes as independent persistent disks to freely attach and detach the volume on any node in the cluster. As a consequence, it is not possible to back up volumes that use snapshots, or to restore volumes from snapshots. See Snapshot Limitations for more information.

Procedure

To create a backup of persistent volumes:

1. Stop the application that is using the persistent volume.

2. Clone the persistent volume.

3. Restart the application.

4. Create a backup of the cloned volume.

5. Delete the cloned volume.

Additional resources

• See About remote health monitoring for more information about the Telemetry service

Configuring an external load balancer

You can configure an OKD cluster to use an external load balancer in place of the default load balancer.

Prerequisites

• On your load balancer, TCP over ports 6443, 443, and 80 must be available to any users of your system.

• Load balance the API port, 6443, between each of the control plane nodes.

• Load balance the application ports, 443 and 80, between all of the compute nodes.

• On your load balancer, port 22623, which is used to serve ignition startup configurations to nodes, is not exposed outside of the cluster.

• Your load balancer must be able to access every machine in your cluster. Methods to allow this access include:

  • Attaching the load balancer to the cluster’s machine subnet.

  • Attaching floating IP addresses to machines that use the load balancer.

Procedure

1. Enable access to the cluster from your load balancer on ports 6443, 443, and 80.

   As an example, note this HAProxy configuration:

   A section of a sample HAProxy configuration

   ...
   listen my-cluster-api-6443
       bind 0.0.0.0:6443
       mode tcp
       balance roundrobin
       server my-cluster-master-2 192.0.2.2:6443 check
       server my-cluster-master-0 192.0.2.3:6443 check
       server my-cluster-master-1 192.0.2.1:6443 check
   listen my-cluster-apps-443
           bind 0.0.0.0:443
           mode tcp
           balance roundrobin
           server my-cluster-worker-0 192.0.2.6:443 check
           server my-cluster-worker-1 192.0.2.5:443 check
           server my-cluster-worker-2 192.0.2.4:443 check
   listen my-cluster-apps-80
           bind 0.0.0.0:80
           mode tcp
           balance roundrobin
           server my-cluster-worker-0 192.0.2.7:80 check
           server my-cluster-worker-1 192.0.2.9:80 check
           server my-cluster-worker-2 192.0.2.8:80 check

2. Add records to your DNS server for the cluster API and apps over the load balancer. For example:

   <load_balancer_ip_address> api.<cluster_name>.<base_domain>
   <load_balancer_ip_address> apps.<cluster_name>.<base_domain>

3. From a command line, use curl to verify that the external load balancer and DNS configuration are operational.

   1. Verify that the cluster API is accessible:

      $ curl https://<loadbalancer_ip_address>:6443/version --insecure

      If the configuration is correct, you receive a JSON object in response:

      {
        "major": "1",
        "minor": "11+",
        "gitVersion": "v1.11.0+ad103ed",
        "gitCommit": "ad103ed",
        "gitTreeState": "clean",
        "buildDate": "2019-01-09T06:44:10Z",
        "goVersion": "go1.10.3",
        "compiler": "gc",
        "platform": "linux/amd64"
      }

   2. Verify that cluster applications are accessible:

      You can also verify application accessibility by opening the OKD console in a web browser.

      $ curl http://console-openshift-console.apps.<cluster_name>.<base_domain> -I -L --insecure

      If the configuration is correct, you receive an HTTP response:

      HTTP/1.1 302 Found
      content-length: 0
      location: https://console-openshift-console.apps.<cluster-name>.<base domain>/
      cache-control: no-cacheHTTP/1.1 200 OK
      referrer-policy: strict-origin-when-cross-origin
      set-cookie: csrf-token=39HoZgztDnzjJkq/JuLJMeoKNXlfiVv2YgZc09c3TBOBU4NI6kDXaJH1LdicNhN1UsQWzon4Dor9GWGfopaTEQ==; Path=/; Secure
      x-content-type-options: nosniff
      x-dns-prefetch-control: off
      x-frame-options: DENY
      x-xss-protection: 1; mode=block
      date: Tue, 17 Nov 2020 08:42:10 GMT
      content-type: text/html; charset=utf-8
      set-cookie: 1e2670d92730b515ce3a1bb65da45062=9b714eb87e93cf34853e87a92d6894be; path=/; HttpOnly; Secure; SameSite=None
      cache-control: private

Next steps

• Customize your cluster.

• If necessary, you can opt out of remote health reporting.

• Set up your registry and configure registry storage.

• Optional: View the events from the vSphere Problem Detector Operator to determine if the cluster has permission or storage configuration issues.