Installing a private cluster on AWS

• You reviewed details about the processes.

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

• You to host the cluster.

• If you use a firewall, you configured it 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 .

Private clusters

You can deploy a private OKD cluster that does not expose external endpoints. Private clusters are accessible from only an internal network and are not visible to the internet.

By default, OKD is provisioned to use publicly-accessible DNS and endpoints. A private cluster sets the DNS, Ingress Controller, and API server to private when you deploy your cluster. This means that the cluster resources are only accessible from your internal network and are not visible to the internet.

To deploy a private cluster, you must:

• Use existing networking that meets your requirements. Your cluster resources might be shared between other clusters on the network.

• Deploy from a machine that has access to:

  • The API services for the cloud to which you provision.

  • The hosts on the network that you provision.

  • The internet to obtain installation media.

You can use any machine that meets these access requirements and follows your company’s guidelines. For example, this machine can be a bastion host on your cloud network or a machine that has access to the network through a VPN.

To create a private cluster on Amazon Web Services (AWS), you must provide an existing private VPC and subnets to host the cluster. The installation program must also be able to resolve the DNS records that the cluster requires. The installation program configures the Ingress Operator and API server for access from only the private network.

The cluster still requires access to internet to access the AWS APIs.

The following items are not required or created when you install a private cluster:

• Public subnets

• Public load balancers, which support public ingress

• A public Route 53 zone that matches the baseDomain for the cluster

The installation program does use the baseDomain that you specify to create a private Route 53 zone and the required records for the cluster. The cluster is configured so that the Operators do not create public records for the cluster and all cluster machines are placed in the private subnets that you specify.

Limitations

The ability to add public functionality to a private cluster is limited.

• You cannot make the Kubernetes API endpoints public after installation without taking additional actions, including creating public subnets in the VPC for each availability zone in use, creating a public load balancer, and configuring the control plane security groups to allow traffic from the internet on 6443 (Kubernetes API port).

• If you use a public Service type load balancer, you must tag a public subnet in each availability zone with kubernetes.io/cluster/<cluster-infra-id>: shared so that AWS can use them to create public load balancers.

About using a custom VPC

In OKD 4.13, you can deploy a cluster into existing subnets in an existing Amazon Virtual Private Cloud (VPC) in Amazon Web Services (AWS). 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. If you cannot obtain the infrastructure creation permissions that are required to create the VPC yourself, use this installation option.

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

If you use a custom VPC, you must correctly configure it and its subnets for the installation program and the cluster to use. See 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 and Route tables for your VPC for more information on configuring networking in an AWS VPC.

Your VPC must meet the following characteristics:

• 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 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.

If you are working in a disconnected environment, you are unable to reach the public IP addresses for EC2, ELB, and S3 endpoints. Depending on the level to which you want to restrict internet traffic during the installation, the following configuration options are available:

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.

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 no more than one public and one private subnet. If you use a private cluster, provide only a private subnet for each availability zone. Otherwise, provide exactly one public and private subnet for each availability zone.

• 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.

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.

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

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

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

Procedure

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

   1	Specify the path and file name, such as ~/.ssh/id_ed25519, of the new SSH key. If you have an existing key pair, ensure your public key is in the your ~/.ssh directory.

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

2. View the public SSH key:

   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 . This pull secret allows you to authenticate with the services that are provided by the included authorities, including Quay.io, which serves the container images for OKD components.

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

   If you do not use the :

   • 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.

Manually creating the installation configuration file

When installing a private OKD cluster, you must manually generate the installation configuration file.

Prerequisites

• You have an SSH public key on your local machine to provide to the installation program. The key will be used for SSH authentication onto your cluster nodes for debugging and disaster recovery.

• You have obtained the OKD installation program and the pull secret for your cluster.

Procedure

1. Create an installation directory to store your required installation assets in:

   $ mkdir <installation_directory>

   You must create a 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 OKD version.

2. Customize the sample install-config.yaml file template that is provided and save it in the <installation_directory>.

   You must name this configuration file install-config.yaml.

   For some platform types, you can alternatively run ./openshift-install create install-config —dir <installation_directory> to generate an install-config.yaml file. You can provide details about your cluster configuration at the prompts.

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 next step of the installation process. You must back it up now.

Installation configuration parameters

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

Required configuration parameters

Required installation configuration parameters are described in the following table:

Network configuration parameters

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

Only IPv4 addresses are supported.

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

networking:
  machineNetwork:
  - cidr: 10.0.0.0/16

Optional configuration parameters

Optional installation configuration parameters are described in the following table:

sshKey:
  <key1>
  <key2>
  <key3>

Optional AWS configuration parameters

Optional AWS configuration parameters are described in the following table:

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

Minimum resource requirements for cluster installation

Each cluster machine must meet the following minimum requirements:

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.

Tested instance types for AWS

The following Amazon Web Services (AWS) instance types have been tested with OKD.

Machine types based on x86_64 architecture

• c4.*

• c5.*

• c5a.*

• i3.*

• m4.*

• m5.*

• m5a.*

• m6i.*

• r4.*

• r5.*

• r5a.*

• r6i.*

• t3.*

• t3a.*

The following Amazon Web Services (AWS) ARM instance types have been tested with OKD.

Machine types based on arm64 architecture

• c6g.*

• m6g.*

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.

apiVersion: v1
baseDomain: example.com (1)
credentialsMode: Mint (2)
controlPlane:  (3) (4)
  hyperthreading: Enabled (5)
  name: master
  platform:
    aws:
      zones:
      - us-west-2a
      - us-west-2b
      rootVolume:
        iops: 4000
        size: 500
        type: io1 (6)
      metadataService:
        authentication: Optional (7)
      type: m6i.xlarge
  replicas: 3
compute: (3)
- hyperthreading: Enabled (5)
  name: worker
  platform:
    aws:
      rootVolume:
        iops: 2000
        size: 500
        type: io1 (6)
      metadataService:
        authentication: Optional (7)
      type: c5.4xlarge
      zones:
      - us-west-2c
  replicas: 3
metadata:
  name: test-cluster (1)
networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14
    hostPrefix: 23
  - cidr: 10.0.0.0/16
  networkType: OVNKubernetes (8)
  serviceNetwork:
  - 172.30.0.0/16
platform:
  aws:
    region: us-west-2 (1)
    propagateUserTags: true (3)
    userTags:
      adminContact: jdoe
      costCenter: 7536
    subnets: (9)
    - subnet-1
    - subnet-2
    - subnet-3
    amiID: ami-96c6f8f7 (10)
    serviceEndpoints: (11)
      - name: ec2
        url: https://vpce-id.ec2.us-west-2.vpce.amazonaws.com
    hostedZone: Z3URY6TWQ91KVV (12)
sshKey: ssh-ed25519 AAAA... (13)
pullSecret: '{"auths": ...}' (1)
publish: Internal (14)

Configuring the cluster-wide proxy during installation

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

Prerequisites

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

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

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

Procedure

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

   apiVersion: v1
   baseDomain: my.domain.com
   proxy:
     httpProxy: http://<username>:<pswd>@<ip>:<port> (1)
     httpsProxy: https://<username>:<pswd>@<ip>:<port> (2)
     noProxy: ec2.<aws_region>.amazonaws.com,elasticloadbalancing.<aws_region>.amazonaws.com,s3.<aws_region>.amazonaws.com (3)
   additionalTrustBundle: | (4)
       -----BEGIN CERTIFICATE-----
       <MY_TRUSTED_CA_CERT>
       -----END CERTIFICATE-----
   additionalTrustBundlePolicy: <policy_to_add_additionalTrustBundle> (5)

   1	A proxy URL to use for creating HTTP connections outside the cluster. The URL scheme must be http.
   2	A proxy URL to use for creating HTTPS connections outside the cluster.
   3	A comma-separated list of destination domain names, IP addresses, or other network CIDRs to exclude from proxying. Preface a domain with . to match subdomains only. For example, .y.com matches x.y.com, but not y.com. Use * to bypass the proxy for all destinations. If you have added the Amazon EC2,Elastic Load Balancing, and S3 VPC endpoints to your VPC, you must add these endpoints to the noProxy field.
   4	If provided, the installation program generates a config map that is named user-ca-bundle in the openshift-config namespace that contains one or more additional CA certificates that are required for proxying HTTPS connections. The Cluster Network Operator then creates a trusted-ca-bundle config map that merges these contents with the Fedora CoreOS (FCOS) trust bundle, and this config map is referenced in the trustedCA field of the Proxy object. The additionalTrustBundle field is required unless the proxy’s identity certificate is signed by an authority from the FCOS trust bundle.
   5	Optional: The policy to determine the configuration of the Proxy object to reference the user-ca-bundle config map in the trustedCA field. The allowed values are Proxyonly and Always. Use Proxyonly to reference the user-ca-bundle config map only when http/https proxy is configured. Use Always to always reference the user-ca-bundle config map. The default value is Proxyonly.

   The installation program does not support the proxy readinessEndpoints field.

   If the installer times out, restart and then complete the deployment by using the wait-for command of the installer. For example: $ ./openshift-install wait-for install-complete —log-level debug

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

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

You can install OKD on a compatible cloud platform.

Prerequisites

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

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

• 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.

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.

Example output

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

Installing the OpenShift CLI by downloading the binary

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

Installing the OpenShift CLI on Linux

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

Procedure

1. Navigate to 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:

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

$ oc <command>

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

Procedure

1. Navigate to and choose the folder for your operating system and architecture.

2. Download oc.zip.

3. Unzip the archive with a ZIP program.

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

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

   C:\> path

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

C:\> oc <command>

Installing the OpenShift CLI on macOS

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

Procedure

1. Navigate to and choose the folder for your operating system and architecture.

2. Download oc.tar.gz.

3. Unpack and unzip the archive.

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

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

   $ echo $PATH

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

$ oc <command>

Logging in to the cluster by using the CLI

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

Prerequisites

• You deployed an OKD cluster.

• You installed the oc CLI.

Procedure

1. Export the kubeadmin credentials:

   $ export KUBECONFIG=<installation_directory>/auth/kubeconfig (1)

   1	For <installation_directory>, specify the path to the directory that you stored the installation files in.

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

   $ oc whoami

   Example output

   system:admin

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:

   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 user.

Additional resources

• See Accessing the web console for more details about accessing and understanding the OKD web console.

Additional resources

• See for more information about the Telemetry service.

Next steps

• .

• Customize your cluster.

• If necessary, you can .

• If necessary, you can remove cloud provider credentials.