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In OKD version 4.12, you can install a cluster on Amazon Web Services (AWS) with remote workers running in AWS Outposts. This can be achieved by customizing the default AWS installation and performing some manual steps.

For more info about AWS Outposts see AWS Outposts Documentation.

In order to install a cluster with remote workers in AWS Outposts, all worker instances must be located within the same Outpost instance and cannot be located in an AWS region. It is not possible for the cluster to have instances in both AWS Outposts and AWS region. In addition, it also follows that control plane nodes mustn’t be schedulable.

Prerequisites

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

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

  • You configured an AWS account to host the cluster.

  • You are familiar with the instance types are supported in the AWS Outpost instance you use. This can be validated with get-outpost-instance-types AWS CLI command

  • You are familiar with the AWS Outpost instance details, such as OutpostArn and AvailabilityZone. This can be validated with list-outposts AWS CLI command

    Since the cluster uses the provided AWS credentials to create AWS resources for its entire life cycle, the credentials must be key-based and long-lived. So, If you have an AWS profile stored on your computer, it must not use a temporary session token, generated while using a multi-factor authentication device. For more information about generating the appropriate keys, see Managing Access Keys for IAM Users in the AWS documentation. You may supply the keys when you run the installation program.

  • You have access to an existing Amazon Virtual Private Cloud (VPC) in Amazon Web Services (AWS). See the section "About using a custom VPC" for more information.

  • If a firewall is used, it was configured to allow the sites that your cluster requires access to.

  • If the cloud identity and access management (IAM) APIs are not accessible in your environment, or if you do not want to store an administrator-level credential secret in the kube-system namespace, you can manually create and maintain IAM credentials.

About using a custom VPC

OKD 4.12 installer cannot automatically deploy AWS Subnets on AWS Outposts, so you will need to manually configure the VPC. Therefore, you have to deploy the cluster into existing subnets in an existing Amazon Virtual Private Cloud (VPC) in Amazon Web Services (AWS). In addition, by deploying OKD into an existing AWS VPC, you might be able to avoid limit constraints in new accounts or more easily abide by the operational constraints that your company’s guidelines set.

Because the installation program cannot know what other components are also in your existing subnets, it cannot choose subnet CIDRs and so forth on your behalf. You must configure networking for the subnets that you install your cluster to yourself.

Requirements for using your VPC

The installation program no longer creates the following components:

  • Internet gateways

  • NAT gateways

  • Subnets

  • Route tables

  • VPCs

  • VPC DHCP options

  • VPC endpoints

The installation program requires that you use the cloud-provided DNS server. Using a custom DNS server is not supported and causes the installation to fail.

If you use a custom VPC, you must correctly configure it and its subnets for the installation program and the cluster to use. See Amazon VPC console wizard configurations and Work with VPCs and subnets in the AWS documentation for more information on creating and managing an AWS VPC.

The installation program cannot:

  • Subdivide network ranges for the cluster to use.

  • Set route tables for the subnets.

  • Set VPC options like DHCP.

You must complete these tasks before you install the cluster. See VPC networking components and Route tables for your VPC for more information on configuring networking in an AWS VPC.

Your VPC must meet the following characteristics:

To allow the creation of OKD with remote workers in the AWS Outposts, you must create at least one private subnet in the AWS Outpost instance for the workload instances creation and one private subnet in an AWS region for the control plane instances creation. If you specify more than one private subnet in the region, the control plane instances will be distributed across these subnets. You will also need to create a public subnet in each of the availability zones used for private subnets, including the Outpost private subnet, as Network Load Balancers will be created in the AWS region for the API server and Ingress network as part of the cluster installation. It is possible to create an AWS region private subnet in the same Availability zone as an Outpost private subnet.

  • Create a public and private subnet in the AWS Region for each availability zone that your control plane uses. Each availability zone can contain no more than one public and one private subnet in the AWS region. For an example of this type of configuration, see VPC with public and private subnets (NAT) in the AWS documentation.

    To create a private subnet in the AWS Outposts, you need to first ensure that the Outpost instance is located in the desired availability zone. Then, you can create the private subnet within that availability zone within the Outpost instance, by adding the Outpost ARN. Make sure there is another public subnet in the AWS Region created in the same availability zone.

    Record each subnet ID. Completing the installation requires that you enter all the subnets IDs, created in the AWS Region, in the platform section of the install-config.yaml file and changing the workers machineset to use the private subnet ID created in the Outpost. See Finding a subnet ID in the AWS documentation.

    In case you need to create a public subnet in the AWS Outposts, verify that this subnet is not used for the Network or Classic LoadBalancer, otherwise the LoadBalancer creation fails. To achieve that, the kubernetes.io/cluster/.*-outposts: owned special tag must be included in the subnet.

  • The VPC’s CIDR block must contain the Networking.MachineCIDR range, which is the IP address pool for cluster machines. The subnet CIDR blocks must belong to the machine CIDR that you specify.

  • The VPC must have a public internet gateway attached to it. For each availability zone:

    • The public subnet requires a route to the internet gateway.

    • The public subnet requires a NAT gateway with an EIP address.

    • The private subnet requires a route to the NAT gateway in public subnet.

    To access your local cluster over your local network, the VPC must be associated with your Outpost’s local gateway route table. For more information, see VPC associations in the AWS Outposts User Guide.

  • The VPC must not use the kubernetes.io/cluster/.*: owned, Name, and openshift.io/cluster tags.

    The installation program modifies your subnets to add the kubernetes.io/cluster/.*: shared tag, so your subnets must have at least one free tag slot available for it. See Tag Restrictions in the AWS documentation to confirm that the installation program can add a tag to each subnet that you specify. You cannot use a Name tag, because it overlaps with the EC2 Name field and the installation fails.

  • You must enable the enableDnsSupport and enableDnsHostnames attributes in your VPC, so that the cluster can use the Route 53 zones that are attached to the VPC to resolve cluster’s internal DNS records. See DNS Support in Your VPC in the AWS documentation.

    If you prefer to use your own Route 53 hosted private zone, you must associate the existing hosted zone with your VPC prior to installing a cluster. You can define your hosted zone using the platform.aws.hostedZone field in the install-config.yaml file.

Option 1: Create VPC endpoints

Create a VPC endpoint and attach it to the subnets that the clusters are using. Name the endpoints as follows:

  • ec2.<aws_region>.amazonaws.com

  • elasticloadbalancing.<aws_region>.amazonaws.com

  • s3.<aws_region>.amazonaws.com

With this option, network traffic remains private between your VPC and the required AWS services.

Option 2: Create a proxy without VPC endpoints

As part of the installation process, you can configure an HTTP or HTTPS proxy. With this option, internet traffic goes through the proxy to reach the required AWS services.

Option 3: Create a proxy with VPC endpoints

As part of the installation process, you can configure an HTTP or HTTPS proxy with VPC endpoints. Create a VPC endpoint and attach it to the subnets that the clusters are using. Name the endpoints as follows:

  • ec2.<aws_region>.amazonaws.com

  • elasticloadbalancing.<aws_region>.amazonaws.com

  • s3.<aws_region>.amazonaws.com

When configuring the proxy in the install-config.yaml file, add these endpoints to the noProxy field. With this option, the proxy prevents the cluster from accessing the internet directly. However, network traffic remains private between your VPC and the required AWS services.

Required VPC components

You must provide a suitable VPC and subnets that allow communication to your machines.

Component AWS type Description

VPC

  • AWS::EC2::VPC

  • AWS::EC2::VPCEndpoint

You must provide a public VPC for the cluster to use. The VPC uses an endpoint that references the route tables for each subnet to improve communication with the registry that is hosted in S3.

Public subnets

  • AWS::EC2::Subnet

  • AWS::EC2::SubnetNetworkAclAssociation

Your VPC must have public subnets for between 1 and 3 availability zones and associate them with appropriate Ingress rules.

Internet gateway

  • AWS::EC2::InternetGateway

  • AWS::EC2::VPCGatewayAttachment

  • AWS::EC2::RouteTable

  • AWS::EC2::Route

  • AWS::EC2::SubnetRouteTableAssociation

  • AWS::EC2::NatGateway

  • AWS::EC2::EIP

You must have a public internet gateway, with public routes, attached to the VPC. In the provided templates, each public subnet has a NAT gateway with an EIP address. These NAT gateways allow cluster resources, like private subnet instances, to reach the internet and are not required for some restricted network or proxy scenarios.

Network access control

  • AWS::EC2::NetworkAcl

  • AWS::EC2::NetworkAclEntry

You must allow the VPC to access the following ports:

Port

Reason

80

Inbound HTTP traffic

443

Inbound HTTPS traffic

22

Inbound SSH traffic

1024 - 65535

Inbound ephemeral traffic

0 - 65535

Outbound ephemeral traffic

Private subnets

  • AWS::EC2::Subnet

  • AWS::EC2::RouteTable

  • AWS::EC2::SubnetRouteTableAssociation

Your VPC can have private subnets. The provided CloudFormation templates can create private subnets for between 1 and 3 availability zones. To enable remote workers running in the Outpost, the VPC must include a private subnet located within the Outpost instance, in addition to the private subnets located within the corresponding AWS region. If you use private subnets, you must provide appropriate routes and tables for them.

VPC validation

To ensure that the subnets that you provide are suitable, the installation program confirms the following data:

  • All the subnets that you specify exist.

  • You provide private subnets.

  • The subnet CIDRs belong to the machine CIDR that you specified.

  • You provide subnets for each availability zone. Each availability zone contains exactly one public and one private subnet in the AWS region (not created in the Outpost instance). The availability zone in which the Outpost instance is installed should include one aditional private subnet in the Outpost instance.

  • You provide a public subnet for each private subnet availability zone. Machines are not provisioned in availability zones that you do not provide private subnets for.

If you destroy a cluster that uses an existing VPC, the VPC is not deleted. When you remove the OKD cluster from a VPC, the kubernetes.io/cluster/.*: shared tag is removed from the subnets that it used.

Division of permissions

Starting with OKD 4.3, you do not need all of the permissions that are required for an installation program-provisioned infrastructure cluster to deploy a cluster. This change mimics the division of permissions that you might have at your company: some individuals can create different resource in your clouds than others. For example, you might be able to create application-specific items, like instances, buckets, and load balancers, but not networking-related components such as VPCs, subnets, or ingress rules.

The AWS credentials that you use when you create your cluster do not need the networking permissions that are required to make VPCs and core networking components within the VPC, such as subnets, routing tables, internet gateways, NAT, and VPN. You still need permission to make the application resources that the machines within the cluster require, such as ELBs, security groups, S3 buckets, and nodes.

Isolation between clusters

If you deploy OKD to an existing network, the isolation of cluster services is reduced in the following ways:

  • You can install multiple OKD clusters in the same VPC.

  • ICMP ingress is allowed from the entire network.

  • TCP 22 ingress (SSH) is allowed to the entire network.

  • Control plane TCP 6443 ingress (Kubernetes API) is allowed to the entire network.

  • Control plane TCP 22623 ingress (MCS) is allowed to the entire network.

Generating a key pair for cluster node SSH access

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

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

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

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.

On clusters running Fedora CoreOS (FCOS), the SSH keys specified in the Ignition config files are written to the /home/core/.ssh/authorized_keys.d/core file. However, the Machine Config Operator manages SSH keys in the /home/core/.ssh/authorized_keys file and configures sshd to ignore the /home/core/.ssh/authorized_keys.d/core file. As a result, newly provisioned OKD nodes are not accessible using SSH until the Machine Config Operator reconciles the machine configs with the authorized_keys file. After you can access the nodes using SSH, you can delete the /home/core/.ssh/authorized_keys.d/core file.

Procedure
  1. If you do not have an existing SSH key pair on your local machine to use for authentication onto your cluster nodes, create one. For example, on a computer that uses a Linux operating system, run the following command:

    $ ssh-keygen -t ed25519 -N '' -f <path>/<file_name> (1)
    1 Specify the path and file name, such as ~/.ssh/id_ed25519, of the new SSH key. If you have an existing key pair, ensure your public key is in the your ~/.ssh directory.

    If you plan to install an OKD cluster that uses FIPS validated 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 OKD, provide the SSH public key to the installation program.

Obtaining the installation program

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

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

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

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

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

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

    $ tar -xvf openshift-install-linux.tar.gz
  3. Download your installation pull secret from the Red Hat OpenShift Cluster Manager. This pull secret allows you to authenticate with the services that are provided by the included authorities, including Quay.io, which serves the container images for OKD components.

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

    • Red Hat Operators are not available.

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

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

Minimum resource requirements for cluster installation

Each cluster machine must meet the following minimum requirements:

Table 1. Minimum resource requirements
Machine Operating System vCPU [1] Virtual RAM Storage Input/Output Per Second (IOPS)[2]

Bootstrap

FCOS

4

16 GB

100 GB

300

Control plane

FCOS

4

16 GB

100 GB

300

Compute

FCOS

2

8 GB

100 GB

300

  1. One vCPU is equivalent to one physical core when simultaneous multithreading (SMT), or hyperthreading, is not enabled. When enabled, use the following formula to calculate the corresponding ratio: (threads per core × cores) × sockets = vCPUs.

  2. OKD and Kubernetes are sensitive to disk performance, and faster storage is recommended, particularly for etcd on the control plane nodes which require a 10 ms p99 fsync duration. Note that on many cloud platforms, storage size and IOPS scale together, so you might need to over-allocate storage volume to obtain sufficient performance.

  3. As with all user-provisioned installations, if you choose to use Fedora compute machines in your cluster, you take responsibility for all operating system life cycle management and maintenance, including performing system updates, applying patches, and completing all other required tasks. Use of Fedora 7 compute machines is deprecated and has been removed in OKD 4.10 and later.

If an instance type for your platform meets the minimum requirements for cluster machines, it is supported to use in OKD.

Additional resources

Identifying your AWS Outposts instance types

AWS Outposts rack catalog includes options supporting the latest generation Intel powered EC2 instance types with or without local instance storage. Identify which instance types are configured in your AWS Outpost instance. As part of the installation process, you must update the install-config.yaml file with the instance type that the installation program will use to deploy worker nodes.

Procedure

Use the AWS CLI to get the list of supported instance types by running the following command:

$ aws outposts get-outpost-instance-types --outpost-id <outpost_id> (1)
1 For <outpost_id>, specify the Outpost ID, used in the AWS account for the worker instances

When you purchase capacity for your AWS Outpost instance, you specify an EC2 capacity layout that each server provides. Each server supports a single family of instance types. A layout can offer a single instance type or multiple instance types. Dedicated Hosts allows you to alter whatever you chose for that initial layout. If you allocate a host to support a single instance type for the entire capacity, you can only start a single instance type from that host.

Supported instance types in AWS Outposts might be changed. For more information, you can check the Compute and Storage page in AWS Outposts documents.

Creating the installation configuration file

You can customize the OKD cluster you install on Amazon Web Services (AWS).

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

  • Obtain service principal permissions at the subscription level.

Procedure
  1. Create the install-config.yaml file.

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

      $ ./openshift-install create install-config --dir <installation_directory> (1)
      1 For <installation_directory>, specify the directory name to store the files that the installation program creates.

      When specifying the directory:

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

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

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

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

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

      2. Select 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 Route 53 service that you configured for your cluster.

      6. Enter a descriptive name for your cluster.

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

  2. Modify the install-config.yaml file. The AWS Outposts installation has the following limitations which require manual modification of the install-config.yaml file:

    • Unlike AWS Regions, which offer near-infinite scale, AWS Outposts are limited by their provisioned capacity, EC2 family and generations, configured instance sizes, and availability of compute capacity that is not already consumed by other workloads. Therefore, when creating new OKD cluster, you need to provide the supported instance type in the compute.platform.aws.type section in the configuration file.

    • When deploying OKD cluster with remote workers running in AWS Outposts, only one Availability Zone can be used for the compute instances - the Availability Zone in which the Outpost instance was created in. Therefore, when creating new OKD cluster, it recommended to provide the relevant Availability Zone in the compute.platform.aws.zones section in the configuration file, in order to limit the compute instances to this Availability Zone.

    • Amazon Elastic Block Store (EBS) gp3 volumes aren’t supported by the AWS Outposts service. This volume type is the default type used by the OKD cluster. Therefore, when creating new OKD cluster, you must change the volume type in the compute.platform.aws.rootVolume.type section to gp2. You will find more information about how to change these values below.

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

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 OKD 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.

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

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. 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 OKD 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). See Supported installation methods for different platforms in Installing documentation for information about instance availability.

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 OKD 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. See Supported installation methods for different platforms in Installing documentation for information about instance availability.

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 ("").

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. 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 to authenticate access to your cluster machines.

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

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

Optional AWS configuration parameters

Optional AWS configuration parameters are described in the following table:

Table 5. Optional AWS parameters
Parameter Description Values

compute.platform.aws.amiID

The AWS AMI used to boot compute machines for the cluster. This is required for regions that require a custom FCOS AMI.

Any published or custom FCOS AMI that belongs to the set AWS region. See FCOS AMIs for AWS infrastructure for available AMI IDs.

compute.platform.aws.iamRole

A pre-existing AWS IAM role applied to the compute machine pool instance profiles. You can use these fields to match naming schemes and include predefined permissions boundaries for your IAM roles. If undefined, the installation program creates a new IAM role.

The name of a valid AWS IAM role.

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 type of the root volume.

Valid AWS EBS volume type, such as io1.

compute.platform.aws.rootVolume.kmsKeyARN

The Amazon Resource Name (key ARN) of a KMS key. This is required to encrypt operating system volumes of worker nodes with a specific KMS key.

compute.platform.aws.type

The EC2 instance type for the compute machines.

Valid AWS instance type, such as m4.2xlarge. See the Supported AWS machine types table that follows.

compute.platform.aws.zones

The availability zones where the installation program creates machines for the compute machine pool. If you provide your own VPC, you must provide a subnet in that availability zone.

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.

Any valid AWS region, such as us-east-1. You can use the AWS CLI to access the regions available based on your selected instance type. For example:

aws ec2 describe-instance-type-offerings --filters Name=instance-type,Values=c7g.xlarge

controlPlane.platform.aws.amiID

The AWS AMI used to boot control plane machines for the cluster. This is required for regions that require a custom FCOS AMI.

Any published or custom FCOS AMI that belongs to the set AWS region. See FCOS AMIs for AWS infrastructure for available AMI IDs.

controlPlane.platform.aws.iamRole

A pre-existing AWS IAM role applied to the control plane machine pool instance profiles. You can use these fields to match naming schemes and include predefined permissions boundaries for your IAM roles. If undefined, the installation program creates a new IAM role.

The name of a valid AWS IAM role.

controlPlane.platform.aws.rootVolume.kmsKeyARN

The Amazon Resource Name (key ARN) of a KMS key. This is required to encrypt operating system volumes of control plane nodes with a specific KMS key.

controlPlane.platform.aws.type

The EC2 instance type for the control plane machines.

Valid AWS instance type, such as m6i.xlarge. See the Supported AWS machine types table that follows.

controlPlane.platform.aws.zones

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

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.

platform.aws.amiID

The AWS AMI used to boot all machines for the cluster. If set, the AMI must belong to the same region as the cluster. This is required for regions that require a custom FCOS AMI.

Any published or custom FCOS AMI that belongs to the set AWS region. See FCOS AMIs for AWS infrastructure for available AMI IDs.

platform.aws.hostedZone

An existing Route 53 private hosted zone for the cluster. You can only use a pre-existing hosted zone when also supplying your own VPC. The hosted zone must already be associated with the user-provided VPC before installation. Also, the domain of the hosted zone must be the cluster domain or a parent of the cluster domain. If undefined, the installation program creates a new hosted zone.

String, for example Z3URY6TWQ91KVV.

platform.aws.serviceEndpoints.name

The AWS service endpoint name. Custom endpoints are only required for cases where alternative AWS endpoints, like FIPS, must be used. Custom API endpoints can be specified for EC2, S3, IAM, Elastic Load Balancing, Tagging, Route 53, and STS AWS services.

Valid AWS service endpoint name.

platform.aws.serviceEndpoints.url

The AWS service endpoint URL. The URL must use the https protocol and the host must trust the certificate.

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.

You can add up to 25 user defined tags during installation. The remaining 25 tags are reserved for OKD.

platform.aws.propagateUserTags

A flag that directs in-cluster Operators to include the specified user tags in the tags of the AWS resources that the Operators create.

Boolean values, for example true or false.

platform.aws.subnets

If you provide the VPC instead of allowing the installation program to create the VPC for you, specify the subnet for the cluster to use. The subnet must be part of the same machineNetwork[].cidr ranges that you specify. For a standard cluster, specify a public and a private subnet for each availability zone. For a private cluster, specify a private subnet for each availability zone.

Valid subnet IDs.

Sample customized install-config.yaml file for AWS

You can customize the installation configuration file (install-config.yaml) to specify more details about your OKD 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)
credentialsMode: Mint (2)
controlPlane:  (3) (4)
  hyperthreading: Enabled (5)
  name: master
  platform: {}
  replicas: 3
compute: (3)
- hyperthreading: Enabled (5)
  name: worker
  platform:
    aws:
      type: m5.large (6)
      zones:
        - us-east-1a (7)
      rootVolume:
        type: gp2 (8)
        size: 120
  replicas: 3
metadata:
  name: test-cluster (1)
networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14
    hostPrefix: 23
  machineNetwork:
  - cidr: 10.0.0.0/16
  networkType: OVNKubernetes (9)
  serviceNetwork:
  - 172.30.0.0/16
platform:
  aws:
    region: us-west-2 (1)
    propagateUserTags: true (3)
    userTags:
      adminContact: jdoe
      costCenter: 7536
  subnets: (10)
  - subnet-1
  - subnet-2
  - subnet-3
sshKey: ssh-ed25519 AAAA... (11)
pullSecret: '{"auths": ...}' (1)
1 Required. The installation program prompts you for this value.
2 Optional: Add this parameter to force the Cloud Credential Operator (CCO) to use the specified mode, instead of having the CCO dynamically try to determine the capabilities of the credentials. For details about CCO modes, see the Cloud Credential Operator entry in the Red Hat Operators reference content.
3 If you do not provide these parameters and values, the installation program provides the default value.
4 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. Only one control plane pool is used.
5 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 simultaneous 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.

6 For compute instances running in an AWS Outpost instance, specify a supported instance type in the AWS Outpost instance.
7 For compute instances running in AWS Outpost instance, specify the Availability Zone where the Outpost instance is located.
8 For compute instances running in AWS Outpost instance, specify volume type gp2, to avoid using gp3 volume type which is not supported.
9 The cluster network plugin to install. The supported values are OVNKubernetes and OpenShiftSDN. The default value is OVNKubernetes.
10 If you provide your own VPC, specify subnets for each availability zone that your cluster uses.
11 You can optionally provide the sshKey value that you use to access the machines in your cluster.

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

Generating manifest files

Use the installation program to generate a set of manifest files in the assets directory. Manifest files are required to specify the AWS Outposts subnets to use for worker machines, and to specify settings required by the network provider.

If you plan to reuse the install-config.yaml file, create a backup file before you generate the manifest files.

Procedure
  1. Optional: Create a backup copy of the install-config.yaml file:

    $ cp install-config.yaml install-config.yaml.backup
  2. Generate a set of manifests in your assets directory:

    $ openshift-install create manifests --dir <installation_-_directory>

    This command displays the following messages.

    Example output
    INFO Consuming Install Config from target directory
    INFO Manifests created in: <installation_directory>/manifests and <installation_directory>/openshift

    The command generates the following manifest files:

    Example output
    $ tree
    .
    ├── manifests
    │   ├── cluster-config.yaml
    │   ├── cluster-dns-02-config.yml
    │   ├── cluster-infrastructure-02-config.yml
    │   ├── cluster-ingress-02-config.yml
    │   ├── cluster-network-01-crd.yml
    │   ├── cluster-network-02-config.yml
    │   ├── cluster-proxy-01-config.yaml
    │   ├── cluster-scheduler-02-config.yml
    │   ├── cvo-overrides.yaml
    │   ├── kube-cloud-config.yaml
    │   ├── kube-system-configmap-root-ca.yaml
    │   ├── machine-config-server-tls-secret.yaml
    │   └── openshift-config-secret-pull-secret.yaml
    └── openshift
        ├── 99_cloud-creds-secret.yaml
        ├── 99_kubeadmin-password-secret.yaml
        ├── 99_openshift-cluster-api_master-machines-0.yaml
        ├── 99_openshift-cluster-api_master-machines-1.yaml
        ├── 99_openshift-cluster-api_master-machines-2.yaml
        ├── 99_openshift-cluster-api_master-user-data-secret.yaml
        ├── 99_openshift-cluster-api_worker-machineset-0.yaml
        ├── 99_openshift-cluster-api_worker-user-data-secret.yaml
        ├── 99_openshift-machineconfig_99-master-ssh.yaml
        ├── 99_openshift-machineconfig_99-worker-ssh.yaml
        ├── 99_role-cloud-creds-secret-reader.yaml
        └── openshift-install-manifests.yaml
    

Modifying manifest files

The AWS Outposts environments has the following limitations which require manual modification in the manifest generated files:

  • The maximum transmission unit (MTU) of a network connection is the size, in bytes, of the largest permissible packet that can be passed over the connection. The Outpost service link supports a maximum packet size of 1300 bytes. For more information about the service link, see Outpost connectivity to AWS Regions

You will find more information about how to change these values below.

  • Use Outpost Subnet for workers machineset

    Modify the following file: <installation_directory>/openshift/99_openshift-cluster-api_worker-machineset-0.yaml Find the subnet ID and replace it with the ID of the private subnet created in the Outpost. As a result, all the worker machines will be created in the Outpost.

  • Specify MTU value for the Network Provider

    Outpost service links support a maximum packet size of 1300 bytes. It’s required to modify the MTU of the Network Provider to follow this requirement. Create a new file under manifests directory, named cluster-network-03-config.yml

    If OpenShift SDN network provider is used, set the MTU value to 1250

    apiVersion: operator.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
      defaultNetwork:
        openshiftSDNConfig:
          mtu: 1250

    If OVN-Kubernetes network provider is used, set the MTU value to 1200

    apiVersion: operator.openshift.io/v1
    kind: Network
    metadata:
      name: cluster
    spec:
      defaultNetwork:
        ovnKubernetesConfig:
          mtu: 1200

Deploying the cluster

You can install OKD on a compatible cloud platform.

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

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

  • Obtain the OKD 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
  1. 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.

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

    The elevated permissions provided by the AdministratorAccess policy are required only during installation.

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.

Installing the OpenShift CLI by downloading the binary

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

If you installed an earlier version of oc, you cannot use it to complete all of the commands in OKD 4.12. Download and install the new version of oc.

Installing the OpenShift CLI on Linux

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

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

  2. Download oc.tar.gz.

  3. Unpack the archive:

    $ tar xvf <file>
  4. Place the oc binary in a directory that is on your PATH.

    To check your PATH, execute the following command:

    $ echo $PATH
Verification
  • After you install the OpenShift CLI, it is available using the oc command:

    $ oc <command>

Installing the OpenShift CLI on Windows

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

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

  2. Download oc.zip.

  3. Unzip the archive with a ZIP program.

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

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

    C:\> path
Verification
  • After you install the OpenShift CLI, it is available using the oc command:

    C:\> oc <command>

Installing the OpenShift CLI on macOS

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

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

  2. Download oc.tar.gz.

  3. Unpack and unzip the archive.

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

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

    $ echo $PATH
Verification
  • After you install the OpenShift CLI, it is available using the oc command:

    $ oc <command>

Logging in to the cluster by using the CLI

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

Prerequisites
  • You deployed an OKD cluster.

  • You installed the oc CLI.

Procedure
  1. Export the kubeadmin credentials:

    $ export KUBECONFIG=<installation_directory>/auth/kubeconfig (1)
    1 For <installation_directory>, specify the path to the directory that you stored the installation files in.
  2. Verify you can run oc commands successfully using the exported configuration:

    $ oc whoami
    Example output
    system:admin

Logging in to the cluster by using the web console

The kubeadmin user exists by default after an OKD installation. You can log in to your cluster as the kubeadmin user by using the OKD web console.

Prerequisites
  • You have access to the installation host.

  • You completed a cluster installation and all cluster Operators are available.

Procedure
  1. Obtain the password for the kubeadmin user from the kubeadmin-password file on the installation host:

    $ cat <installation_directory>/auth/kubeadmin-password

    Alternatively, you can obtain the kubeadmin password from the <installation_directory>/.openshift_install.log log file on the installation host.

  2. List the OKD web console route:

    $ oc get routes -n openshift-console | grep 'console-openshift'

    Alternatively, you can obtain the OKD route from the <installation_directory>/.openshift_install.log log file on the installation host.

    Example output
    console     console-openshift-console.apps.<cluster_name>.<base_domain>            console     https   reencrypt/Redirect   None
  3. Navigate to the route detailed in the output of the preceding command in a web browser and log in as the kubeadmin user.

Additional resources

Cluster Limitations

Network Load Balancer (NLB) and Classic Load Balancer are not supported on AWS Outposts. After the cluster is created, all the Load Balancers are created in the AWS region. In order to use Load Balancers created inside the Outpost instances, Application Load Balancer should be used. The AWS Load Balancer Operator can be used in order to achieve that goal.

If you want to use a public subnet located in the outpost instance for the ALB, you need to remove the special tag (kubernetes.io/cluster/.*-outposts: owned) that was added earlier during the VPC creation. This will prevent you from creating new Services of type LoadBalancer (Network Load Balancer).

Persistent storage using AWS Elastic Block Store limitations

  • AWS Outposts does not support Amazon Elastic Block Store (EBS) gp3 volumes. After installation, the cluster includes two storage classes - gp3-csi and gp2-csi, with gp3-csi being the default storage class. It is important to always use gp2-csi. You can change the default storage class using the following OpenShift CLI (oc) commands:

    $ oc annotate --overwrite storageclass gp3-csi storageclass.kubernetes.io/is-default-class=false
    $ oc annotate --overwrite storageclass gp2-csi storageclass.kubernetes.io/is-default-class=true
  • To create a Volume in the Outpost instance, the CSI driver determines the Outpost ARN based on the topology keys stored on the CSINode objects. To ensure that the CSI driver uses the correct topology values, it is necessary to use the WaitForConsumer volume binding mode and avoid setting allowed topologies on any new storage class created.