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Installing a cluster on OpenStack with customizations

Prerequisites

  • Review details about the OpenShift Container Platform installation and update processes.

  • Have a storage service installed in RHOSP, like Block Storage (Cinder) or Object Storage (Swift). Object storage is the recommended storage technology for OpenShift Container Platform registry cluster deployment. For more information, see Optimizing storage.

  • Have metadata service enabled in RHOSP

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

112 GB

vCPUs

28

Volume storage

275 GB

Instances

7

Security groups

3

Security group rules

60

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 and compute machines

By default, the OpenShift Container Platform installation process stands up three control plane and three compute machines.

Each machine requires:

  • An instance from the RHOSP quota

  • A port from the RHOSP quota

  • A flavor with at least 16 GB memory, 4 vCPUs, and 25 GB storage space

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, 4 vCPUs, and 25 GB storage space

Internet and Telemetry access for OpenShift Container Platform

In OpenShift Container Platform 4.6, you require access to the internet to install your cluster. The Telemetry service, which runs by default to provide metrics about cluster health and the success of updates, also requires internet access. If your cluster is connected to the internet, Telemetry runs automatically, and your cluster is registered to the Red Hat OpenShift Cluster Manager (OCM).

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

You must have internet access to:

  • Access the Red Hat OpenShift Cluster Manager page to download the installation program and perform subscription management. If the cluster has internet access and you do not disable Telemetry, that service automatically entitles your cluster.

  • Access Quay.io to obtain the packages that are required to install your cluster.

  • Obtain the packages that are required to perform cluster updates.

If your cluster cannot have direct internet access, you can perform a restricted network installation on some types of infrastructure that you provision. During that process, you download the content that is required and use it to populate a mirror registry with the packages that you need to install a cluster and generate the installation program. With some installation types, the environment that you install your cluster in will not require internet access. Before you update the cluster, you update the content of the mirror registry.

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.
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.

Verifying external network access

The OpenShift Container Platform installation process requires external network access. You must provide an external network value to it, or deployment fails. Before you begin the process, verify that a network with the External router type exists in Red Hat OpenStack Platform (RHOSP).

Prerequisites
Procedure

  1. Using the RHOSP CLI, verify the name and ID of the 'External' network:

    $ openstack network list --long -c ID -c Name -c "Router Type"
    Example output
    +--------------------------------------+----------------+-------------+
| ID                                   | Name           | Router Type |
+--------------------------------------+----------------+-------------+
| 148a8023-62a7-4672-b018-003462f8d7dc | public_network | External    |
+--------------------------------------+----------------+-------------+

A network with an External router type appears in the network list. If at least one does not, see Creating a default floating IP network and Creating a default provider network.

If the external network’s CIDR range overlaps one of the default network ranges, you must change the matching network ranges in the install-config.yaml file before you start the installation process.

The default network ranges are:

Network Range

machineNetwork

10.0.0.0/16

serviceNetwork

172.30.0.0/16

clusterNetwork

10.128.0.0/14
If the installation program finds multiple networks with the same name, it sets one of them at random. To avoid this behavior, create unique names for resources in RHOSP.

If the Neutron trunk service plug-in is enabled, a trunk port is created by default. For more information, see Neutron trunk port.

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: shiftstack_user
      password: XXX
      user_domain_name: Default
      project_domain_name: Default
  dev-env:
    region_name: RegionOne
    auth:
      username: 'devuser'
      password: XXX
      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 machine to the certificate authority trust bundle:

      $ sudo cp ca.crt.pem /etc/pki/ca-trust/source/anchors/

    3. Update the trust bundle:

      $ sudo update-ca-trust extract

    4. 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.

Obtaining the installation program

Before you install OpenShift Container Platform, download the installation file on a local computer.

Prerequisites

  • A computer that runs Linux or macOS, with 500 MB of local disk space

Procedure

  1. Access the Infrastructure Provider page on the Red Hat OpenShift Cluster Manager site. If you have a Red Hat account, log in with your credentials. If you do not, create an account.

  2. Navigate to the page for your installation type, download the installation program for your operating system, and place the file in the directory where you will store the installation configuration files.

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

    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 OpenShift Container Platform uninstallation procedures for your specific cloud provider.

  3. 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

  4. From the Pull Secret page on the Red Hat OpenShift Cluster Manager site, download your installation pull secret as a .txt file. This pull secret allows you to authenticate with the services that are provided by the included authorities, including Quay.io, which serves the container images for OpenShift Container Platform components.

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.

Procedure

  1. Create the install-config.yaml file.

    1. 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.

      Specify an empty directory. Some installation assets, like bootstrap X.509 certificates have short expiration intervals, so you must not reuse an installation directory. If you want to reuse individual files from another cluster installation, you can copy them into your directory. However, the file names for the installation assets might change between releases. Use caution when copying installation files from an earlier OpenShift Container Platform version.

    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 and 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 that you obtained from the Pull Secret page on the Red Hat OpenShift Cluster Manager site.

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

  3. 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 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.
Table 2. Required parameters
Parameter Description Values

apiVersion

The API version for the install-config.yaml content. The current version is v1. The installer 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: aws, baremetal, azure, openstack, ovirt, vsphere. For additional information about platform.<platform> parameters, consult the following table for your specific platform.

Object

pullSecret

Get this pull secret from https://cloud.redhat.com/openshift/install/pull-secret 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"
      }
   }
}
Table 3. 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

compute

The configuration for the machines that comprise the compute nodes.

Array of machine-pool objects. For details, see the following "Machine-pool" table.

compute.architecture

Determines the instruction set architecture of the machines in the pool. Currently, heteregeneous clusters are not supported, so 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.

aws, azure, gcp, 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.

controlPlane

The configuration for the machines that comprise the control plane.

Array of machine-pool objects. For details, see the following "Machine-pool" table.

controlPlane.architecture

Determines the instruction set architecture of the machines in the pool. Currently, heteregeneous clusters are not supported, so 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.

aws, azure, gcp, openstack, ovirt, vsphere, or {}

controlPlane.replicas

The number of control plane machines to provision.

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

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 on CCO modes, see the Cloud Credential Operator entry in the Red Hat Operators reference content.

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.

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

networking

The configuration for the Pod network provider in the cluster.

Object

networking.clusterNetwork

The IP address pools for pods. The default is 10.128.0.0/14 with a host prefix of /23.

Array of objects

networking.clusterNetwork.cidr

Required if you use networking.clusterNetwork. The IP block address pool.

IP network. IP networks are represented as strings using Classless Inter-Domain Routing (CIDR) notation with a traditional IP address or network number, followed by the forward slash (/) character, followed by a decimal value between 0 and 32 that describes the number of significant bits. For example, 10.0.0.0/16 represents IP addresses 10.0.0.0 through 10.0.255.255.

networking.clusterNetwork.hostPrefix

Required if you use networking.clusterNetwork. The prefix size to allocate to each node from the CIDR. For example, 24 would allocate 2^8=256 adresses to each node.

Integer

networking.machineNetwork

The IP address pools for machines.

Array of objects

networking.machineNetwork.cidr

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

IP network. IP networks are represented as strings using Classless Inter-Domain Routing (CIDR) notation with a traditional IP address or network number, followed by the forward slash (/) character, followed by a decimal value between 0 and 32 that describes the number of significant bits. For example, 10.0.0.0/16 represents IP addresses 10.0.0.0 through 10.0.255.255.

networking.networkType

The type of network to install. The default is OpenShiftSDN.

String

networking.serviceNetwork

The IP address pools for services. The default is 172.30.0.0/16.

Array of IP networks. IP networks are represented as strings using Classless Inter-Domain Routing (CIDR) notation with a traditional IP address or network number, followed by the forward slash (/) character, followed by a decimal value between 0 and 32 that describes the number of significant bits. For example, 10.0.0.0/16 represents IP addresses 10.0.0.0 through 10.0.255.255.

publish

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

Internal or External. To deploy a private cluster, which cannot be accessed from the internet, set publish to Internal. The default value is External.

sshKey

The SSH key or keys to authenticate 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.

One or more keys. For example:

sshKey:
  <key1>
  <key2>
  <key3>
Table 4. Additional Red Hat OpenStack Platform (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.

String, for example m1.xlarge.
Table 5. 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 installer 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.additionalNetworkIDs

Additional networks that are associated with control plane 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.

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 installer 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"].

platform.openstack.clusterOSImage

The location from which the installer 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.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.lbFloatingIP

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.

Custom subnets in RHOSP deployments

Optionally, you can deploy a cluster on a Red Hat OpenStack Platform (RHOSP) subnet of your choice. The subnet’s GUID is passed as the value of platform.openstack.machinesSubnet in the install-config.yaml file.

This subnet is used as the cluster’s primary subnet; nodes and ports are created on it.

Before you run the OpenShift Container Platform installer with a custom subnet, verify that:

  • The target network and subnet are available.

  • DHCP is enabled on the target subnet.

  • You can provide installer credentials that have permission to create ports on the target network.

  • If your network configuration requires a router, it is created in RHOSP. Some configurations rely on routers for floating IP address translation.

  • Your network configuration does not rely on a provider network. Provider networks are not supported.

By default, the API VIP takes x.x.x.5 and the Ingress VIP takes x.x.x.7 from your network’s CIDR block. To override these default values, set values for platform.openstack.apiVIP and platform.openstack.ingressVIP that are outside of the DHCP allocation pool.

Sample customized install-config.yaml file for RHOSP

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
clusterID: os-test
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: OpenShiftSDN
platform:
  openstack:
    cloud: mycloud
    externalNetwork: external
    computeFlavor: m1.xlarge
    lbFloatingIP: 128.0.0.1
fips: false
pullSecret: '{"auths": ...}'
sshKey: ssh-ed25519 AAAA...

Generating an SSH private key and adding it to the agent

If you want to perform installation debugging or disaster recovery on your cluster, you must provide an SSH key to both your ssh-agent and the installation program. You can use this key to access the bootstrap machine in a public cluster to troubleshoot installation issues.

In a production environment, you require disaster recovery and debugging.

You can use this key to SSH into the master nodes as the user core. When you deploy the cluster, the key is added to the core user’s ~/.ssh/authorized_keys list.

Procedure

  1. If you do not have an SSH key that is configured for password-less authentication on your computer, create one. For example, on a computer that uses a Linux operating system, run the following command:

    $ ssh-keygen -t rsa -b 4096 -N '' \
    -f <path>/<file_name> (1)
    1 Specify the path and file name, such as ~/.ssh/id_rsa, of the new SSH key.

    Running this command generates an SSH key that does not require a password in the location that you specified.

  2. Start the ssh-agent process as a background task:

    $ eval "$(ssh-agent -s)"
    Example output
    Agent pid 31874

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

    $ ssh-add <path>/<file_name> (1)
    Example output
    Identity added: /home/<you>/<path>/<file_name> (<computer_name>)
    1 Specify the path and file name for your SSH private key, such as ~/.ssh/id_rsa
Next steps

  • When you install OpenShift Container Platform, provide the SSH public key to the installation program.

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 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.

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

    • platform.openstack.ingressFloatingIP

    • platform.openstack.lbFloatingIP

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.lbFloatingIP

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.

Procedure

  1. Run the installation program:

    $ ./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.

    When the cluster deployment completes, directions for accessing your cluster, including a link to its web console and credentials for the kubeadmin user, display in your terminal.

    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.

    You must not delete the installation program or the files that the installation program creates. Both are required to delete the cluster.

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

You can log in to your cluster as a default system user by exporting the cluster kubeconfig file. The kubeconfig file contains information about the cluster that is used by the CLI to connect a client to the correct cluster and API server. The file is specific to a cluster and is created during OpenShift Container Platform installation.

Prerequisites

  • Deploy an OpenShift Container Platform cluster.

  • Install the oc CLI.

Procedure

  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

Next steps