In OpenShift Container Platform version 4.1, you can install a customized cluster on infrastructure that the installation program provisions on Amazon Web Services (AWS). To customize the installation, you modify some parameters in the install-config.yaml file before you install the cluster.

Prerequisites

Internet and Telemetry access for OpenShift Container Platform

In OpenShift Container Platform 4.1, Telemetry is the component that provides metrics about cluster health and the success of updates. To perform subscription management, including legally entitling your purchase from Red Hat, you must use the Telemetry service and access the Red Hat OpenShift Cluster Manager page.

Because there is no disconnected subscription management, you cannot both opt out of sending data back to Red Hat and entitle your purchase. Support for disconnected subscription management might be added in future releases of OpenShift Container Platform

Your machines must have direct internet access to install the cluster.

You must have internet access to:

  • Access the Infrastructure Provider page on the Red Hat OpenShift Cluster Manager site to download the installation program

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

  • Obtain the packages that are required to perform cluster updates

  • Access Red Hat’s software as a service page to perform subscription management

Generating an SSH private key and adding it to the agent

For production OpenShift Container Platform clusters on which you want to perform installation debugging or disaster recovery, you must provide an SSH key that your ssh-agent process uses to the installer.

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

You must use a local key, not one that you configured with platform-specific approaches such as AWS key pairs.

Procedure
  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 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)"
    
    Agent pid 31874
  3. Add your SSH private key to the ssh-agent:

    $ ssh-add <path>/<file_name> (1)
    
    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 installer. If you install a cluster on infrastructure that you provision, you must provide this key to your cluster’s machines.

Obtaining the installation program

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

Prerequisites
  • You must install the cluster from a computer that uses Linux or macOS.

  • You need 300 MB of local disk space to download the installation program.

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.

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

    $ tar xvf <installation_program>.tar.gz
  4. From the Pull Secret page on the Red Hat OpenShift Cluster Manager site, download your installation pull secret as a .txt file or copy it to your clipboard. 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 your installation of OpenShift Container Platform on a compatible cloud.

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, you must provide an SSH key that your ssh-agent process uses to the installation program.

      2. Select AWS as the platform to target.

      3. If you do not have an Amazon Web Services (AWS) profile stored on your computer, enter the AWS access key ID and secret access key for the user that you configured to run the installation program.

      4. Select the AWS region to deploy the cluster to.

      5. Select the base domain for the Route53 service that you configured for your cluster.

      6. Enter a descriptive name for your cluster.

      7. 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 and in the Go documentation.

  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 Amazon Web Services (AWS) account 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.

You cannot modify these parameters after installation.

Table 1. Required parameters
Parameter Description Values

baseDomain

The base domain of your cloud provider. This value 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.

controlPlane.platform

The cloud provider to host the control plane machines. This parameter value must match the compute.platform parameter value.

aws

compute.platform

The cloud provider to host the worker machines. This parameter value must match the controlPlane.platform parameter value.

aws

metadata.name

The name of your cluster.

A string that contains uppercase or lowercase letters, such as dev.

platform.aws.region

The region to deploy your cluster in.

A valid AWS region, such as us-east-1.

pullSecret

The pull secret that you obtained from the Pull Secret page on the Red Hat OpenShift Cluster Manager site. You use this pull secret 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.

{
   "auths":{
      "cloud.openshift.com":{
         "auth":"b3Blb=",
         "email":"you@example.com"
      },
      "quay.io":{
         "auth":"b3Blb=",
         "email":"you@example.com"
      }
   }
}
Table 2. Optional AWS platform parameters
Parameter Description Values

sshKey

The 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, you must provide an SSH key that your ssh-agent process uses to the installation program.

A valid, local public SSH key that you added to the ssh-agent process.

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.platform.aws.rootVolume.iops

The Input/Output Operations Per Second (IOPS) that is reserved for the root volume.

Integer, for example 4000.

compute.platform.aws.rootVolume.size

The size in GiB of the root volume.

Integer, for example 500.

compute.platform.aws.rootVolume.type

The instance type of the root volume.

Valid AWS EBS instance type, such as io1.

compute.platform.aws.type

The EC2 instance type for the compute machines.

Valid AWS instance type, such as c5.9xlarge.

compute.platform.aws.zones

The availability zones where the installation program creates machines for the compute MachinePool.

A list of valid AWS availability zones, such as us-east-1c, in a YAML sequence.

compute.aws.region

The AWS region that the installation program creates compute resources in.

Valid AWS region, such as us-east-1.

compute.replicas

The number of compute, or worker, machines to provision.

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

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.platform.aws.type

The EC2 instance type for the control plane machines.

Valid AWS instance type, such as c5.9xlarge.

controlPlane.platform.aws.zones

The availability zones where the installation program creates machines for the control plane MachinePool.

A list of valid AWS availability zones, such as us-east-1c, in a YAML sequence.

controlPlane.aws.region

The AWS region that the installation program creates control plane resources in.

Valid AWS region, such as us-east-1.

controlPlane.replicas

The number of control plane machines to provision.

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

platform.aws.userTags

A map of keys and values that the installation program adds as tags to all resources that it creates.

Any valid YAML map, such as key value pairs in the <key>: <value> format. For more information about AWS tags, see Tagging Your Amazon EC2 Resources in the AWS documentation.

Sample customized install-config.yaml file for AWS

You can customize the install-config.yaml file to specify more details about your OpenShift Container Platform cluster’s platform or modify the values of the required parameters.

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

apiVersion: v1
baseDomain: example.com (1)
controlPlane: (2)
  hyperthreading: Enabled  (3) (4)
  name: master
  platform:
    aws:
      zones:
      - us-west-2a
      - us-west-2b
      rootVolume:
        iops: 4000
        size: 500
        type: io1
      type: m5.xlarge (4)
  replicas: 3
compute: (2)
- hyperthreading: Enabled (3)
  name: worker
  platform:
    aws:
      rootVolume:
        iops: 2000
        size: 500
        type: io1 (5)
      type: c5.4xlarge
      zones:
      - us-west-2c
  replicas: 3
metadata:
  name: test-cluster (1)
networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14
    hostPrefix: 23
  machineCIDR: 10.0.0.0/16
  networkType: OpenShiftSDN
  serviceNetwork:
  - 172.30.0.0/16
platform:
  aws:
    region: us-west-2 (1)
    userTags:
      adminContact: jdoe
      costCenter: 7536
pullSecret: '{"auths": ...}' (1)
sshKey: ssh-ed25519 AAAA... (6)
1 Required. The installation program prompts you for this value.
2 If you do not provide these parameters and values, the installation program provides the default value.
3 The controlPlane section is a single mapping, but the compute section is a sequence of mappings. To meet the requirements of the different data structures, the first line of the compute section must begin with a hyphen, -, and the first line of the controlPlane section must not. Although both sections currently define a single machine pool, it is possible that future versions of OpenShift Container Platform will support defining multiple compute pools during installation. Only one control plane pool is used.
4 Whether to enable or disable simultaneous multithreading, or hyperthreading. By default, simultaneous multithreading is enabled to increase the performance of your machines' cores. You can disable it by setting the parameter value to Disabled. If you disable simultanous multithreading in some cluster machines, you must disable it in all cluster machines.

If you disable simultaneous multithreading, ensure that your capacity planning accounts for the dramatically decreased machine performance. Use larger instance types, such as m4.2xlarge or m5.2xlarge, for your machines if you disable simultaneous multithreading.

5 To configure faster storage for etcd, especially for larger clusters, set the storage type as io1 and set iops to 2000.
6 You can optionally provide the sshKey value that you use to access the machines in your cluster.

For production OpenShift Container Platform clusters on which you want to perform installation debugging or disaster recovery, you must provide an SSH key that your ssh-agent process uses to the installation program.

Deploy the cluster

You can install OpenShift Container Platform on a compatible cloud.

You can run the installation program only once, during initial installation.

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

  • 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. You must keep the cluster running for 24 hours in a non-degraded state to ensure that the first certificate rotation has finished.

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

  2. Optional: Remove or disable the AdministratorAccess policy from the IAM account that you used to install the cluster.

Installing the OpenShift Command-line Interface

You can download and install the OpenShift Command-line Interface (CLI), commonly known as oc.

If you installed an earlier version of oc, you cannot use it to complete all of the commands in OpenShift Container Platform 4.1. You must download and install the new version of oc.

Procedure
  1. From the Infrastructure Provider page on the Red Hat OpenShift Cluster Manager site, navigate to the page for your installation type and click Download Command-line Tools.

  2. From the site that is displayed, download the compressed file for your operating system.

    You can install oc on Linux, Windows, or macOS.

  3. Extract the compressed file and place it in a directory that is on your PATH.

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)
    
    $ oc whoami
    system:admin
    1 For <installation_directory>, specify the path to the directory that you stored the installation files in.
Next steps