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Installing a cluster on OpenStack in a restricted network - Installing on OpenStack | Installing | OpenShift Container Platform 4.12
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Installing a cluster on OpenStack in a restricted network

Prerequisites

About installations in restricted networks

In OpenShift Container Platform 4.12, you can perform an installation that does not require an active connection to the internet to obtain software components. Restricted network installations can be completed using installer-provisioned infrastructure or user-provisioned infrastructure, depending on the cloud platform to which you are installing the cluster.

If you choose to perform a restricted network installation on a cloud platform, you still require access to its cloud APIs. Some cloud functions, like Amazon Web Service’s Route 53 DNS and IAM services, require internet access. Depending on your network, you might require less internet access for an installation on bare metal hardware, Nutanix, or on VMware vSphere.

To complete a restricted network installation, you must create a registry that mirrors the contents of the OpenShift image registry and contains the installation media. You can create this registry on a mirror host, which can access both the internet and your closed network, or by using other methods that meet your restrictions.

Additional limits

Clusters in restricted networks have the following additional limitations and restrictions:

  • The ClusterVersion status includes an Unable to retrieve available updates error.

  • By default, you cannot use the contents of the Developer Catalog because you cannot access the required image stream tags.

Resource guidelines for installing OpenShift Container Platform on RHOSP

To support an OpenShift Container Platform installation, your Red Hat OpenStack Platform (RHOSP) quota must meet the following requirements:

Table 1. Recommended resources for a default OpenShift Container Platform cluster on RHOSP
Resource Value

Floating IP addresses

3

Ports

15

Routers

1

Subnets

1

RAM

88 GB

vCPUs

22

Volume storage

275 GB

Instances

7

Security groups

3

Security group rules

60

Server groups

2 - plus 1 for each additional availability zone in each machine pool

A cluster might function with fewer than recommended resources, but its performance is not guaranteed.

If RHOSP object storage (Swift) is available and operated by a user account with the swiftoperator role, it is used as the default backend for the OpenShift Container Platform image registry. In this case, the volume storage requirement is 175 GB. Swift space requirements vary depending on the size of the image registry.
By default, your security group and security group rule quotas might be low. If you encounter problems, run openstack quota set --secgroups 3 --secgroup-rules 60 <project> as an administrator to increase them.

An OpenShift Container Platform deployment comprises control plane machines, compute machines, and a bootstrap machine.

Control plane machines

By default, the OpenShift Container Platform installation process creates three control plane machines.

Each machine requires:

  • An instance from the RHOSP quota

  • A port from the RHOSP quota

  • A flavor with at least 16 GB memory and 4 vCPUs

  • At least 100 GB storage space from the RHOSP quota

Compute machines

By default, the OpenShift Container Platform installation process creates three compute machines.

Each machine requires:

  • An instance from the RHOSP quota

  • A port from the RHOSP quota

  • A flavor with at least 8 GB memory and 2 vCPUs

  • At least 100 GB storage space from the RHOSP quota

Compute machines host the applications that you run on OpenShift Container Platform; aim to run as many as you can.

Bootstrap machine

During installation, a bootstrap machine is temporarily provisioned to stand up the control plane. After the production control plane is ready, the bootstrap machine is deprovisioned.

The bootstrap machine requires:

  • An instance from the RHOSP quota

  • A port from the RHOSP quota

  • A flavor with at least 16 GB memory and 4 vCPUs

  • At least 100 GB storage space from the RHOSP quota

Internet access for OpenShift Container Platform

In OpenShift Container Platform 4.12, you require access to the internet to obtain the images that are necessary to install your cluster.

You must have internet access to:

  • Access OpenShift Cluster Manager Hybrid Cloud Console 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 required content and use it to populate a mirror registry with the installation packages. 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.

Enabling Swift on RHOSP

Swift is operated by a user account with the swiftoperator role. Add the role to an account before you run the installation program.

If the Red Hat OpenStack Platform (RHOSP) object storage service, commonly known as Swift, is available, OpenShift Container Platform uses it as the image registry storage. If it is unavailable, the installation program relies on the RHOSP block storage service, commonly known as Cinder.

If Swift is present and you want to use it, you must enable access to it. If it is not present, or if you do not want to use it, skip this section.

RHOSP 17 sets the rgw_max_attr_size parameter of Ceph RGW to 256 characters. This setting causes issues with uploading container images to the OpenShift Container Platform registry. You must set the value of rgw_max_attr_size to at least 1024 characters.

Before installation, check if your RHOSP deployment is affected by this problem. If it is, reconfigure Ceph RGW.
Prerequisites

  • You have a RHOSP administrator account on the target environment.

  • The Swift service is installed.

  • On Ceph RGW, the account in url option is enabled.

Procedure

To enable Swift on RHOSP:

  1. As an administrator in the RHOSP CLI, add the swiftoperator role to the account that will access Swift:

    $ openstack role add --user <user> --project <project> swiftoperator

Your RHOSP deployment can now use Swift for the image registry.

Defining parameters for the installation program

The OpenShift Container Platform installation program relies on a file that is called clouds.yaml. The file describes Red Hat OpenStack Platform (RHOSP) configuration parameters, including the project name, log in information, and authorization service URLs.

Procedure

  1. Create the clouds.yaml file:

    • If your RHOSP distribution includes the Horizon web UI, generate a clouds.yaml file in it.

      Remember to add a password to the auth field. You can also keep secrets in a separate file from clouds.yaml.

    • If your RHOSP distribution does not include the Horizon web UI, or you do not want to use Horizon, create the file yourself. For detailed information about clouds.yaml, see Config files in the RHOSP documentation.

      clouds:
  shiftstack:
    auth:
      auth_url: http://10.10.14.42:5000/v3
      project_name: shiftstack
      username: <username>
      password: <password>
      user_domain_name: Default
      project_domain_name: Default
  dev-env:
    region_name: RegionOne
    auth:
      username: <username>
      password: <password>
      project_name: 'devonly'
      auth_url: 'https://10.10.14.22:5001/v2.0'

  2. If your RHOSP installation uses self-signed certificate authority (CA) certificates for endpoint authentication:

    1. Copy the certificate authority file to your machine.

    2. Add the cacerts key to the clouds.yaml file. The value must be an absolute, non-root-accessible path to the CA certificate:

      clouds:
  shiftstack:
    ...
    cacert: "/etc/pki/ca-trust/source/anchors/ca.crt.pem"

      After you run the installer with a custom CA certificate, you can update the certificate by editing the value of the ca-cert.pem key in the cloud-provider-config keymap. On a command line, run:

      $ oc edit configmap -n openshift-config cloud-provider-config

  3. Place the clouds.yaml file in one of the following locations:

    1. The value of the OS_CLIENT_CONFIG_FILE environment variable

    2. The current directory

    3. A Unix-specific user configuration directory, for example ~/.config/openstack/clouds.yaml

    4. A Unix-specific site configuration directory, for example /etc/openstack/clouds.yaml

      The installation program searches for clouds.yaml in that order.

Setting OpenStack Cloud Controller Manager options

Optionally, you can edit the OpenStack Cloud Controller Manager (CCM) configuration for your cluster. This configuration controls how OpenShift Container Platform interacts with Red Hat OpenStack Platform (RHOSP).

For a complete list of configuration parameters, see the "OpenStack Cloud Controller Manager reference guide" page in the "Installing on OpenStack" documentation.

Procedure

  1. If you have not already generated manifest files for your cluster, generate them by running the following command:

    $ openshift-install --dir <destination_directory> create manifests

  2. In a text editor, open the cloud-provider configuration manifest file. For example:

    $ vi openshift/manifests/cloud-provider-config.yaml

  3. Modify the options according to the CCM reference guide.

    Configuring Octavia for load balancing is a common case for clusters that do not use Kuryr. For example:

    #...
[LoadBalancer]
use-octavia=true (1)
lb-provider = "amphora" (2)
floating-network-id="d3deb660-4190-40a3-91f1-37326fe6ec4a" (3)
create-monitor = True (4)
monitor-delay = 10s (5)
monitor-timeout = 10s (6)
monitor-max-retries = 1 (7)
#...
    1 This property enables Octavia integration.
    2 This property sets the Octavia provider that your load balancer uses. It accepts "ovn" or "amphora" as values. If you choose to use OVN, you must also set lb-method to SOURCE_IP_PORT.
    3 This property is required if you want to use multiple external networks with your cluster. The cloud provider creates floating IP addresses on the network that is specified here.
    4 This property controls whether the cloud provider creates health monitors for Octavia load balancers. Set the value to True to create health monitors. As of RHOSP 16.2, this feature is only available for the Amphora provider.
    5 This property sets the frequency with which endpoints are monitored. The value must be in the time.ParseDuration() format. This property is required if the value of the create-monitor property is True.
    6 This property sets the time that monitoring requests are open before timing out. The value must be in the time.ParseDuration() format. This property is required if the value of the create-monitor property is True.
    7 This property defines how many successful monitoring requests are required before a load balancer is marked as online. The value must be an integer. This property is required if the value of the create-monitor property is True.

    Prior to saving your changes, verify that the file is structured correctly. Clusters might fail if properties are not placed in the appropriate section.

    You must set the value of the create-monitor property to True if you use services that have the value of the .spec.externalTrafficPolicy property set to Local. The OVN Octavia provider in RHOSP 16.2 does not support health monitors. Therefore, services that have ETP parameter values set to Local might not respond when the lb-provider value is set to "ovn".

    For installations that use Kuryr, Kuryr handles relevant services. There is no need to configure Octavia load balancing in the cloud provider.

  4. Save the changes to the file and proceed with installation.

    You can update your cloud provider configuration after you run the installer. On a command line, run:

    $ oc edit configmap -n openshift-config cloud-provider-config

    After you save your changes, your cluster will take some time to reconfigure itself. The process is complete if none of your nodes have a SchedulingDisabled status.

Creating the RHCOS image for restricted network installations

Download the Red Hat Enterprise Linux CoreOS (RHCOS) image to install OpenShift Container Platform on a restricted network Red Hat OpenStack Platform (RHOSP) environment.

Prerequisites

  • Obtain the OpenShift Container Platform installation program. For a restricted network installation, the program is on your mirror registry host.

Procedure

  1. Log in to the Red Hat Customer Portal’s Product Downloads page.

  2. Under Version, select the most recent release of OpenShift Container Platform 4.12 for RHEL 8.

    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.

  3. Download the Red Hat Enterprise Linux CoreOS (RHCOS) - OpenStack Image (QCOW) image.

  4. Decompress the image.

    You must decompress the image before the cluster can use it. The name of the downloaded file might not contain a compression extension, like .gz or .tgz. To find out if or how the file is compressed, in a command line, enter:

    $ file <name_of_downloaded_file>

  5. Upload the image that you decompressed to a location that is accessible from the bastion server, like Glance. For example:

    $ openstack image create --file rhcos-44.81.202003110027-0-openstack.x86_64.qcow2 --disk-format qcow2 rhcos-${RHCOS_VERSION}

    Depending on your RHOSP environment, you might be able to upload the image in either .raw or .qcow2 formats. If you use Ceph, you must use the .raw format.

    If the installation program finds multiple images with the same name, it chooses one of them at random. To avoid this behavior, create unique names for resources in RHOSP.

The image is now available for a restricted installation. Note the image name or location for use in OpenShift Container Platform deployment.

Creating the installation configuration file

You can customize the OpenShift Container Platform cluster you install on Red Hat OpenStack Platform (RHOSP).

Prerequisites

  • Obtain the OpenShift Container Platform installation program and the pull secret for your cluster. For a restricted network installation, these files are on your mirror host.

  • Have the imageContentSources values that were generated during mirror registry creation.

  • Obtain the contents of the certificate for your mirror registry.

  • Retrieve a Red Hat Enterprise Linux CoreOS (RHCOS) image and upload it to an accessible location.

  • 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 OpenShift Container Platform 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 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.

      2. Select openstack as the platform to target.

      3. Specify the Red Hat OpenStack Platform (RHOSP) external network name to use for installing the cluster.

      4. Specify the floating IP address to use for external access to the OpenShift API.

      5. Specify a RHOSP flavor with at least 16 GB RAM to use for control plane nodes and 8 GB RAM for compute nodes.

      6. Select the base domain to deploy the cluster to. All DNS records will be sub-domains of this base and will also include the cluster name.

      7. Enter a name for your cluster. The name must be 14 or fewer characters long.

      8. Paste the pull secret from the Red Hat OpenShift Cluster Manager.

  2. In the install-config.yaml file, set the value of platform.openstack.clusterOSImage to the image location or name. For example:

    platform:
  openstack:
      clusterOSImage: http://mirror.example.com/images/rhcos-43.81.201912131630.0-openstack.x86_64.qcow2.gz?sha256=ffebbd68e8a1f2a245ca19522c16c86f67f9ac8e4e0c1f0a812b068b16f7265d

  3. Edit the install-config.yaml file to give the additional information that is required for an installation in a restricted network.

    1. Update the pullSecret value to contain the authentication information for your registry:

      pullSecret: '{"auths":{"<mirror_host_name>:5000": {"auth": "<credentials>","email": "you@example.com"}}}'

      For <mirror_host_name>, specify the registry domain name that you specified in the certificate for your mirror registry, and for <credentials>, specify the base64-encoded user name and password for your mirror registry.

    2. Add the additionalTrustBundle parameter and value.

      additionalTrustBundle: |
  -----BEGIN CERTIFICATE-----
  ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ
  -----END CERTIFICATE-----

      The value must be the contents of the certificate file that you used for your mirror registry. The certificate file can be an existing, trusted certificate authority, or the self-signed certificate that you generated for the mirror registry.

    3. Add the image content resources, which resemble the following YAML excerpt:

      imageContentSources:
- mirrors:
  - <mirror_host_name>:5000/<repo_name>/release
  source: quay.io/openshift-release-dev/ocp-release
- mirrors:
  - <mirror_host_name>:5000/<repo_name>/release
  source: registry.redhat.io/ocp/release

      For these values, use the imageContentSources that you recorded during mirror registry creation.

  4. Make any other modifications to the install-config.yaml file that you require. You can find more information about the available parameters in the Installation configuration parameters section.

  5. 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.

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 OpenShift Container Platform cluster to use a proxy by configuring the proxy settings in the install-config.yaml file.

Kuryr installations default to HTTP proxies.
Prerequisites

  • For Kuryr installations on restricted networks that use the Proxy object, the proxy must be able to reply to the router that the cluster uses. To add a static route for the proxy configuration, from a command line as the root user, enter:

    $ ip route add <cluster_network_cidr> via <installer_subnet_gateway>

  • The restricted subnet must have a gateway that is defined and available to be linked to the Router resource that Kuryr creates.

  • 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 Red Hat OpenStack Platform (RHOSP), 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.
    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 Red Hat Enterprise Linux CoreOS (RHCOS) 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 RHCOS 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.

    If the installer times out, restart and then complete the deployment by using the wait-for command of the installer. For example:

    $ ./openshift-install wait-for install-complete --log-level debug

  2. Save the file and reference it when installing OpenShift Container Platform.

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.

Only the Proxy object named cluster is supported, and no additional proxies can be created.

Installation configuration parameters

Before you deploy an OpenShift Container Platform 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.

After installation, you cannot modify these parameters in the install-config.yaml file.

Required configuration parameters

Required installation configuration parameters are described in the following table:

Table 2. Required parameters
Parameter Description Values

apiVersion

The API version for the install-config.yaml content. The current version is v1. The installation program may also support older API versions.

String

baseDomain

The base domain of your cloud provider. The base domain is used to create routes to your OpenShift Container Platform cluster components. The full DNS name for your cluster is a combination of the baseDomain and metadata.name parameter values that uses the <metadata.name>.<baseDomain> format.

A fully-qualified domain or subdomain name, such as example.com.

metadata

Kubernetes resource ObjectMeta, from which only the name parameter is consumed.

Object

metadata.name

The name of the cluster. DNS records for the cluster are all subdomains of {{.metadata.name}}.{{.baseDomain}}.

String of lowercase letters, hyphens (-), and periods (.), such as dev. The string must be 14 characters or fewer long.

platform

The configuration for the specific platform upon which to perform the installation: alibabacloud, aws, baremetal, azure, gcp, ibmcloud, nutanix, openstack, ovirt, vsphere, or {}. For additional information about platform.<platform> parameters, consult the table for your specific platform that follows.

Object

pullSecret

Get a pull secret from the Red Hat OpenShift Cluster Manager to authenticate downloading container images for OpenShift Container Platform components from services such as Quay.io.

 
{
   "auths":{
      "cloud.openshift.com":{
         "auth":"b3Blb=",
         "email":"you@example.com"
      },
      "quay.io":{
         "auth":"b3Blb=",
         "email":"you@example.com"
      }
   }
}

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.

Globalnet is not supported with Red Hat OpenShift Data Foundation disaster recovery solutions. For regional disaster recovery scenarios, ensure that you use a nonoverlapping range of private IP addresses for the cluster and service networks in each cluster.
Table 3. Network parameters
Parameter Description Values

networking

The configuration for the cluster network.

Object

You cannot modify parameters specified by the networking object after installation.

networking.networkType

The Red Hat OpenShift Networking network plugin to install.

Either OpenShiftSDN or OVNKubernetes. OpenShiftSDN is a CNI plugin for all-Linux networks. OVNKubernetes is a CNI plugin for Linux networks and hybrid networks that contain both Linux and Windows servers. The default value is OVNKubernetes.

networking.clusterNetwork

The IP address blocks for pods.

The default value is 10.128.0.0/14 with a host prefix of /23.

If you specify multiple IP address blocks, the blocks must not overlap.

An array of objects. For example:

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

networking.clusterNetwork.cidr

Required if you use networking.clusterNetwork. An IP address block.

An IPv4 network.

An IP address block in Classless Inter-Domain Routing (CIDR) notation. The prefix length for an IPv4 block is between 0 and 32.

networking.clusterNetwork.hostPrefix

The subnet prefix length to assign to each individual node. For example, if hostPrefix is set to 23 then each node is assigned a /23 subnet out of the given cidr. A hostPrefix value of 23 provides 510 (2^(32 - 23) - 2) pod IP addresses.

A subnet prefix.

The default value is 23.

networking.serviceNetwork

The IP address block for services. The default value is 172.30.0.0/16.

The OpenShift SDN and OVN-Kubernetes network plugins support only a single IP address block for the service network.

An array with an IP address block in CIDR format. For example:

networking:
  serviceNetwork:
   - 172.30.0.0/16

networking.machineNetwork

The IP address blocks for machines.

If you specify multiple IP address blocks, the blocks must not overlap.

An array of objects. For example:

networking:
  machineNetwork:
  - cidr: 10.0.0.0/16

networking.machineNetwork.cidr

Required if you use networking.machineNetwork. An IP address block. The default value is 10.0.0.0/16 for all platforms other than libvirt. For libvirt, the default value is 192.168.126.0/24.

An IP network block in CIDR notation.

For example, 10.0.0.0/16.

Set the networking.machineNetwork to match the CIDR that the preferred NIC resides in.

Optional configuration parameters

Optional installation configuration parameters are described in the following table:

Table 4. Optional parameters
Parameter Description Values

additionalTrustBundle

A PEM-encoded X.509 certificate bundle that is added to the nodes' trusted certificate store. This trust bundle may also be used when a proxy has been configured.

String

capabilities

Controls the installation of optional core cluster components. You can reduce the footprint of your OpenShift Container Platform cluster by disabling optional components. For more information, see the "Cluster capabilities" page in Installing.

String array

capabilities.baselineCapabilitySet

Selects an initial set of optional capabilities to enable. Valid values are None, v4.11, v4.12 and vCurrent. The default value is vCurrent.

String

capabilities.additionalEnabledCapabilities

Extends the set of optional capabilities beyond what you specify in baselineCapabilitySet. You may specify multiple capabilities in this parameter.

String array

compute

The configuration for the machines that comprise the compute nodes.

Array of MachinePool objects.

compute.architecture

Determines the instruction set architecture of the machines in the pool. Currently, clusters with varied architectures are not supported. All pools must specify the same architecture. Valid values are amd64 (the default).

String

compute.hyperthreading

Whether to enable or disable simultaneous multithreading, or hyperthreading, on compute machines. By default, simultaneous multithreading is enabled to increase the performance of your machines' cores.

If you disable simultaneous multithreading, ensure that your capacity planning accounts for the dramatically decreased machine performance.

Enabled or Disabled

compute.name

Required if you use compute. The name of the machine pool.

worker

compute.platform

Required if you use compute. Use this parameter to specify the cloud provider to host the worker machines. This parameter value must match the controlPlane.platform parameter value.

alibabacloud, aws, azure, gcp, ibmcloud, nutanix, openstack, ovirt, vsphere, or {}

compute.replicas

The number of compute machines, which are also known as worker machines, to provision.

A positive integer greater than or equal to 2. The default value is 3.

featureSet

Enables the cluster for a feature set. A feature set is a collection of OpenShift Container Platform features that are not enabled by default. For more information about enabling a feature set during installation, see "Enabling features using feature gates".

String. The name of the feature set to enable, such as TechPreviewNoUpgrade.

controlPlane

The configuration for the machines that comprise the control plane.

Array of MachinePool objects.

controlPlane.architecture

Determines the instruction set architecture of the machines in the pool. Currently, clusters with varied architectures are not supported. All pools must specify the same architecture. Valid values are amd64 (the default).

String

controlPlane.hyperthreading

Whether to enable or disable simultaneous multithreading, or hyperthreading, on control plane machines. By default, simultaneous multithreading is enabled to increase the performance of your machines' cores.

If you disable simultaneous multithreading, ensure that your capacity planning accounts for the dramatically decreased machine performance.

Enabled or Disabled

controlPlane.name

Required if you use controlPlane. The name of the machine pool.

master

controlPlane.platform

Required if you use controlPlane. Use this parameter to specify the cloud provider that hosts the control plane machines. This parameter value must match the compute.platform parameter value.

alibabacloud, aws, azure, gcp, ibmcloud, nutanix, openstack, ovirt, vsphere, or {}

controlPlane.replicas

The number of control plane machines to provision.

The only supported value is 3, which is the default value.

credentialsMode

The Cloud Credential Operator (CCO) mode. If no mode is specified, the CCO dynamically tries to determine the capabilities of the provided credentials, with a preference for mint mode on the platforms where multiple modes are supported.

Not all CCO modes are supported for all cloud providers. For more information about CCO modes, see the Cloud Credential Operator entry in the Cluster Operators reference content.

If your AWS account has service control policies (SCP) enabled, you must configure the credentialsMode parameter to Mint, Passthrough or Manual.

Mint, Passthrough, Manual or an empty string ("").

fips

Enable or disable fips mode. The default is false (disabled). 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.

To enable fips mode for your cluster, you must run the installation program from a Red Hat Enterprise Linux (RHEL) computer configured to operate in fips mode. For more information about configuring fips mode on RHEL, see Installing the system in fips mode. The use of fips validated or Modules In Process cryptographic libraries is only supported on OpenShift Container Platform deployments on the x86_64, ppc64le, and s390x architectures.

If you are using Azure File storage, you cannot enable fips mode.

false or true

imageContentSources

Sources and repositories for the release-image content.

Array of objects. Includes a source and, optionally, mirrors, as described in the following rows of this table.

imageContentSources.source

Required if you use imageContentSources. Specify the repository that users refer to, for example, in image pull specifications.

String

imageContentSources.mirrors

Specify one or more repositories that may also contain the same images.

Array of strings

publish

How to publish or expose the user-facing endpoints of your cluster, such as the Kubernetes API, OpenShift routes.

Internal or External. The default value is External.

Setting this field to Internal is not supported on non-cloud platforms.

If the value of the field is set to Internal, the cluster will become non-functional. For more information, refer to BZ#1953035.

sshKey

The SSH key to authenticate access to your cluster machines.

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.

For example, sshKey: ssh-ed25519 AAAA...

Additional Red Hat OpenStack Platform (RHOSP) configuration parameters

Additional RHOSP configuration parameters are described in the following table:

Table 5. Additional RHOSP parameters
Parameter Description Values

compute.platform.openstack.rootVolume.size

For compute machines, the size in gigabytes of the root volume. If you do not set this value, machines use ephemeral storage.

Integer, for example 30.

compute.platform.openstack.rootVolume.type

For compute machines, the root volume’s type.

String, for example performance.

controlPlane.platform.openstack.rootVolume.size

For control plane machines, the size in gigabytes of the root volume. If you do not set this value, machines use ephemeral storage.

Integer, for example 30.

controlPlane.platform.openstack.rootVolume.type

For control plane machines, the root volume’s type.

String, for example performance.

platform.openstack.cloud

The name of the RHOSP cloud to use from the list of clouds in the clouds.yaml file.

String, for example MyCloud.

platform.openstack.externalNetwork

The RHOSP external network name to be used for installation.

String, for example external.

platform.openstack.computeFlavor

The RHOSP flavor to use for control plane and compute machines.

This property is deprecated. To use a flavor as the default for all machine pools, add it as the value of the type key in the platform.openstack.defaultMachinePlatform property. You can also set a flavor value for each machine pool individually.

String, for example m1.xlarge.

Optional RHOSP configuration parameters

Optional RHOSP configuration parameters are described in the following table:

Table 6. Optional RHOSP parameters
Parameter Description Values

compute.platform.openstack.additionalNetworkIDs

Additional networks that are associated with compute machines. Allowed address pairs are not created for additional networks.

A list of one or more UUIDs as strings. For example, fa806b2f-ac49-4bce-b9db-124bc64209bf.

compute.platform.openstack.additionalSecurityGroupIDs

Additional security groups that are associated with compute machines.

A list of one or more UUIDs as strings. For example, 7ee219f3-d2e9-48a1-96c2-e7429f1b0da7.

compute.platform.openstack.zones

RHOSP Compute (Nova) availability zones (AZs) to install machines on. If this parameter is not set, the installation program relies on the default settings for Nova that the RHOSP administrator configured.

On clusters that use Kuryr, RHOSP Octavia does not support availability zones. Load balancers and, if you are using the Amphora provider driver, OpenShift Container Platform services that rely on Amphora VMs, are not created according to the value of this property.

A list of strings. For example, ["zone-1", "zone-2"].

compute.platform.openstack.rootVolume.zones

For compute machines, the availability zone to install root volumes on. If you do not set a value for this parameter, the installation program selects the default availability zone.

A list of strings, for example ["zone-1", "zone-2"].

compute.platform.openstack.serverGroupPolicy

Server group policy to apply to the group that will contain the compute machines in the pool. You cannot change server group policies or affiliations after creation. Supported options include anti-affinity, soft-affinity, and soft-anti-affinity. The default value is soft-anti-affinity.

An affinity policy prevents migrations and therefore affects RHOSP upgrades. The affinity policy is not supported.

If you use a strict anti-affinity policy, an additional RHOSP host is required during instance migration.

A server group policy to apply to the machine pool. For example, soft-affinity.

controlPlane.platform.openstack.additionalNetworkIDs

Additional networks that are associated with control plane machines. Allowed address pairs are not created for additional networks.

Additional networks that are attached to a control plane machine are also attached to the bootstrap node.

A list of one or more UUIDs as strings. For example, fa806b2f-ac49-4bce-b9db-124bc64209bf.

controlPlane.platform.openstack.additionalSecurityGroupIDs

Additional security groups that are associated with control plane machines.

A list of one or more UUIDs as strings. For example, 7ee219f3-d2e9-48a1-96c2-e7429f1b0da7.

controlPlane.platform.openstack.zones

RHOSP Compute (Nova) availability zones (AZs) to install machines on. If this parameter is not set, the installation program relies on the default settings for Nova that the RHOSP administrator configured.

On clusters that use Kuryr, RHOSP Octavia does not support availability zones. Load balancers and, if you are using the Amphora provider driver, OpenShift Container Platform services that rely on Amphora VMs, are not created according to the value of this property.

A list of strings. For example, ["zone-1", "zone-2"].

controlPlane.platform.openstack.rootVolume.zones

For control plane machines, the availability zone to install root volumes on. If you do not set this value, the installation program selects the default availability zone.

A list of strings, for example ["zone-1", "zone-2"].

controlPlane.platform.openstack.serverGroupPolicy

Server group policy to apply to the group that will contain the control plane machines in the pool. You cannot change server group policies or affiliations after creation. Supported options include anti-affinity, soft-affinity, and soft-anti-affinity. The default value is soft-anti-affinity.

An affinity policy prevents migrations, and therefore affects RHOSP upgrades. The affinity policy is not supported.

If you use a strict anti-affinity policy, an additional RHOSP host is required during instance migration.

A server group policy to apply to the machine pool. For example, soft-affinity.

platform.openstack.clusterOSImage

The location from which the installation program downloads the RHCOS image.

You must set this parameter to perform an installation in a restricted network.

An HTTP or HTTPS URL, optionally with an SHA-256 checksum.

For example, http://mirror.example.com/images/rhcos-43.81.201912131630.0-openstack.x86_64.qcow2.gz?sha256=ffebbd68e8a1f2a245ca19522c16c86f67f9ac8e4e0c1f0a812b068b16f7265d. The value can also be the name of an existing Glance image, for example my-rhcos.

platform.openstack.clusterOSImageProperties

Properties to add to the installer-uploaded ClusterOSImage in Glance. This property is ignored if platform.openstack.clusterOSImage is set to an existing Glance image.

You can use this property to exceed the default persistent volume (PV) limit for RHOSP of 26 PVs per node. To exceed the limit, set the hw_scsi_model property value to virtio-scsi and the hw_disk_bus value to scsi.

You can also use this property to enable the QEMU guest agent by including the hw_qemu_guest_agent property with a value of yes.

A list of key-value string pairs. For example, ["hw_scsi_model": "virtio-scsi", "hw_disk_bus": "scsi"].

platform.openstack.defaultMachinePlatform

The default machine pool platform configuration.

 
{
   "type": "ml.large",
   "rootVolume": {
      "size": 30,
      "type": "performance"
   }
}

platform.openstack.ingressFloatingIP

An existing floating IP address to associate with the Ingress port. To use this property, you must also define the platform.openstack.externalNetwork property.

An IP address, for example 128.0.0.1.

platform.openstack.apiFloatingIP

An existing floating IP address to associate with the API load balancer. To use this property, you must also define the platform.openstack.externalNetwork property.

An IP address, for example 128.0.0.1.

platform.openstack.externalDNS

IP addresses for external DNS servers that cluster instances use for DNS resolution.

A list of IP addresses as strings. For example, ["8.8.8.8", "192.168.1.12"].

platform.openstack.machinesSubnet

The UUID of a RHOSP subnet that the cluster’s nodes use. Nodes and virtual IP (VIP) ports are created on this subnet.

The first item in networking.machineNetwork must match the value of machinesSubnet.

If you deploy to a custom subnet, you cannot specify an external DNS server to the OpenShift Container Platform installer. Instead, add DNS to the subnet in RHOSP.

A UUID as a string. For example, fa806b2f-ac49-4bce-b9db-124bc64209bf.

Sample customized install-config.yaml file for restricted OpenStack installations

This sample install-config.yaml demonstrates all of the possible Red Hat OpenStack Platform (RHOSP) customization options.

This sample file is provided for reference only. You must obtain your install-config.yaml file by using the installation program.

 
apiVersion: v1
baseDomain: example.com
controlPlane:
  name: master
  platform: {}
  replicas: 3
compute:
- name: worker
  platform:
    openstack:
      type: ml.large
  replicas: 3
metadata:
  name: example
networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14
    hostPrefix: 23
  machineNetwork:
  - cidr: 10.0.0.0/16
  serviceNetwork:
  - 172.30.0.0/16
  networkType: OVNKubernetes
platform:
  openstack:
    region: region1
    cloud: mycloud
    externalNetwork: external
    computeFlavor: m1.xlarge
    apiFloatingIP: 128.0.0.1
fips: false
pullSecret: '{"auths": ...}'
sshKey: ssh-ed25519 AAAA...
additionalTrustBundle: |

  -----BEGIN CERTIFICATE-----

  ZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ

  -----END CERTIFICATE-----

imageContentSources:
- mirrors:
  - <mirror_registry>/<repo_name>/release
  source: quay.io/openshift-release-dev/ocp-release
- mirrors:
  - <mirror_registry>/<repo_name>/release
  source: quay.io/openshift-release-dev/ocp-v4.0-art-dev

Generating a key pair for cluster node SSH access

During an OpenShift Container Platform installation, you can provide an SSH public key to the installation program. The key is passed to the Red Hat Enterprise Linux CoreOS (RHCOS) 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 RHCOS 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.

Do not skip this procedure in production environments, where disaster recovery and debugging is required.

You must use a local key, not one that you configured with platform-specific approaches such as AWS key pairs.
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 OpenShift Container Platform cluster that uses fips validated or Modules In Process cryptographic libraries on the x86_64, ppc64le, and s390x architectures. 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 OpenShift Container Platform, provide the SSH public key to the installation program.

Enabling access to the environment

At deployment, all OpenShift Container Platform machines are created in a Red Hat OpenStack Platform (RHOSP)-tenant network. Therefore, they are not accessible directly in most RHOSP deployments.

You can configure OpenShift Container Platform API and application access by using floating IP addresses (fips) during installation. You can also complete an installation without configuring fips, but the installer will not configure a way to reach the API or applications externally.

Enabling access with floating IP addresses

Create floating IP (FIP) addresses for external access to the OpenShift Container Platform API and cluster applications.

Procedure

  1. Using the Red Hat OpenStack Platform (RHOSP) CLI, create the API FIP:

    $ openstack floating ip create --description "API <cluster_name>.<base_domain>" <external_network>

  2. Using the Red Hat OpenStack Platform (RHOSP) CLI, create the apps, or Ingress, FIP:

    $ openstack floating ip create --description "Ingress <cluster_name>.<base_domain>" <external_network>

  3. Add records that follow these patterns to your DNS server for the API and Ingress fips:

    api.<cluster_name>.<base_domain>.  IN  A  <API_FIP>
*.apps.<cluster_name>.<base_domain>. IN  A <apps_FIP>

    If you do not control the DNS server, you can access the cluster by adding the cluster domain names such as the following to your /etc/hosts file:

    • <api_floating_ip> api.<cluster_name>.<base_domain>

    • <application_floating_ip> grafana-openshift-monitoring.apps.<cluster_name>.<base_domain>

    • <application_floating_ip> prometheus-k8s-openshift-monitoring.apps.<cluster_name>.<base_domain>

    • <application_floating_ip> oauth-openshift.apps.<cluster_name>.<base_domain>

    • <application_floating_ip> console-openshift-console.apps.<cluster_name>.<base_domain>

    • application_floating_ip integrated-oauth-server-openshift-authentication.apps.<cluster_name>.<base_domain>

    The cluster domain names in the /etc/hosts file grant access to the web console and the monitoring interface of your cluster locally. You can also use the kubectl or oc. You can access the user applications by using the additional entries pointing to the <application_floating_ip>. This action makes the API and applications accessible to only you, which is not suitable for production deployment, but does allow installation for development and testing.

  4. Add the fips to the install-config.yaml file as the values of the following parameters:

    • platform.openstack.ingressFloatingIP

    • platform.openstack.apiFloatingIP

If you use these values, you must also enter an external network as the value of the platform.openstack.externalNetwork parameter in the install-config.yaml file.

You can make OpenShift Container Platform resources available outside of the cluster by assigning a floating IP address and updating your firewall configuration.

Completing installation without floating IP addresses

You can install OpenShift Container Platform on Red Hat OpenStack Platform (RHOSP) without providing floating IP addresses.

In the install-config.yaml file, do not define the following parameters:

  • platform.openstack.ingressFloatingIP

  • platform.openstack.apiFloatingIP

If you cannot provide an external network, you can also leave platform.openstack.externalNetwork blank. If you do not provide a value for platform.openstack.externalNetwork, a router is not created for you, and, without additional action, the installer will fail to retrieve an image from Glance. You must configure external connectivity on your own.

If you run the installer from a system that cannot reach the cluster API due to a lack of floating IP addresses or name resolution, installation fails. To prevent installation failure in these cases, you can use a proxy network or run the installer from a system that is on the same network as your machines.

You can enable name resolution by creating DNS records for the API and Ingress ports. For example:

api.<cluster_name>.<base_domain>.  IN  A  <api_port_IP>
*.apps.<cluster_name>.<base_domain>. IN  A <ingress_port_IP>

If you do not control the DNS server, you can add the record to your /etc/hosts file. This action makes the API accessible to only you, which is not suitable for production deployment but does allow installation for development and testing.

Deploying the cluster

You can install OpenShift Container Platform on a compatible cloud platform.

You can run the create cluster command of the installation program only once, during initial installation.
Prerequisites

  • Obtain the OpenShift Container Platform installation program and the pull secret for your cluster.

  • Verify the cloud provider account on your host has the correct permissions to deploy the cluster. An account with incorrect permissions causes the installation process to fail with an error message that displays the missing permissions.

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.

    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.

Do not delete the installation program or the files that the installation program creates. Both are required to delete the cluster.
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: "password"
INFO Time elapsed: 36m22s

  • 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.

  • It is recommended that you use Ignition config files within 12 hours after they are generated because the 24-hour certificate rotates from 16 to 22 hours after the cluster is installed. By using the Ignition config files within 12 hours, you can avoid installation failure if the certificate update runs during installation.

Verifying cluster status

You can verify your OpenShift Container Platform cluster’s status during or after installation.

Procedure

  1. In the cluster environment, export the administrator’s kubeconfig file:

    $ export KUBECONFIG=<installation_directory>/auth/kubeconfig (1)
    1 For <installation_directory>, specify the path to the directory that you stored the installation files in.

    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.

  2. View the control plane and compute machines created after a deployment:

    $ oc get nodes

  3. View your cluster’s version:

    $ oc get clusterversion

  4. View your Operators' status:

    $ oc get clusteroperator

  5. View all running pods in the cluster:

    $ oc get pods -A

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 OpenShift Container Platform installation.

Prerequisites

  • You deployed an OpenShift Container Platform 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
Additional resources

  • See Accessing the web console for more details about accessing and understanding the OpenShift Container Platform web console.

Disabling the default OperatorHub catalog sources

Operator catalogs that source content provided by Red Hat and community projects are configured for OperatorHub by default during an OpenShift Container Platform installation. In a restricted network environment, you must disable the default catalogs as a cluster administrator.

Procedure

  • Disable the sources for the default catalogs by adding disableAllDefaultSources: true to the OperatorHub object:

    $ oc patch OperatorHub cluster --type json \
    -p '[{"op": "add", "path": "/spec/disableAllDefaultSources", "value": true}]'

Alternatively, you can use the web console to manage catalog sources. From the Administration → Cluster Settings → Configuration → OperatorHub page, click the Sources tab, where you can create, update, delete, disable, and enable individual sources.

Telemetry access for OpenShift Container Platform

In OpenShift Container Platform 4.12, the Telemetry service, which runs by default to provide metrics about cluster health and the success of updates, requires internet access. If your cluster is connected to the internet, Telemetry runs automatically, and your cluster is registered to OpenShift Cluster Manager Hybrid Cloud Console.

After you confirm that your OpenShift Cluster Manager Hybrid Cloud Console inventory is correct, either maintained automatically by Telemetry or manually by using OpenShift Cluster Manager, use subscription watch to track your OpenShift Container Platform subscriptions at the account or multi-cluster level.

Additional resources

Next steps