Installing a private cluster on IBM Cloud VPC

In OKD version 4.12, you can install a private cluster into an existing VPC. The installation program provisions the rest of the required infrastructure, which you can further customize. To customize the installation, you modify parameters in the install-config.yaml file before you install the cluster.

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 IBM Cloud account to host the cluster.

• If you use a firewall, you configured it to allow the sites that your cluster requires access to.

• You configured the ccoctl utility before you installed the cluster. For more information, see Configuring IAM for IBM Cloud VPC.

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.

• Create a DNS zone using IBM Cloud DNS Services and specify it as the base domain of the cluster. For more information, see “Using IBM Cloud DNS Services to configure DNS resolution”.

• 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.

Private clusters in IBM Cloud VPC

To create a private cluster on IBM Cloud VPC, 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 only internal traffic.

The cluster still requires access to internet to access the IBM Cloud VPC APIs.

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

• Public subnets

• Public network load balancers, which support public ingress

• A public DNS zone that matches the baseDomain for the cluster

The installation program does use the baseDomain that you specify to create a private DNS 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

Private clusters on IBM Cloud VPC are subject only to the limitations associated with the existing VPC that was used for cluster deployment.

About using a custom VPC

In OKD 4.12, you can deploy a cluster into the subnets of an existing IBM Virtual Private Cloud (VPC). Deploying OKD into an existing VPC can help you 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 in your existing subnets, it cannot choose subnet CIDRs and so forth. You must configure networking for the subnets to which you will install the cluster.

Requirements for using your VPC

You must correctly configure the existing VPC and its subnets before you install the cluster. The installation program does not create the following components:

• NAT gateways

• Subnets

• Route tables

• VPC network

The installation program cannot:

• Subdivide network ranges for the cluster to use

• Set route tables for the subnets

• Set VPC options like DHCP

VPC validation

The VPC and all of the subnets must be in an existing resource group. The cluster is deployed to this resource group.

As part of the installation, specify the following in the install-config.yaml file:

• The name of the resource group

• The name of VPC

• The subnets for control plane machines and compute machines

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

• All of the subnets that you specify exist.

• For each availability zone in the region, you specify:

  • One subnet for control plane machines.

  • One subnet for compute machines.

• The machine CIDR that you specified contains the subnets for the compute machines and control plane machines.

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 to the entire network.

• TCP port 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.

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 / 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:

   $ 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 a bastion host on your cloud network or a machine that has access to the to the network through a VPN.

For more information about private cluster installation requirements, see “Private clusters”.

Prerequisites

• You have a machine that runs Linux, for example Red Hat Enterprise Linux 8, 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.

   If you do not use the pull secret from the Red Hat OpenShift Cluster Manager:

   • 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.

Exporting the IBM Cloud VPC API key

You must set the IBM Cloud VPC API key you created as a global variable; the installation program ingests the variable during startup to set the API key.

Prerequisites

• You have created either a user API key or service ID API key for your IBM Cloud account.

Procedure

• Export your IBM Cloud VPC API key as a global variable:

  $ export IC_API_KEY=<api_key>

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.

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:
  serviceNetwork:
   - 172.30.0.0/16

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>

Additional IBM Cloud VPC configuration parameters

Additional IBM Cloud VPC configuration parameters are described in the following table:

1. To determine which profile best meets your needs, see Instance Profiles in the IBM documentation.

Minimum resource requirements for cluster installation

Each cluster machine must meet the following minimum requirements:

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

Sample customized install-config.yaml file for IBM Cloud VPC

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

apiVersion: v1
baseDomain: example.com (1)
controlPlane:  (2) (3)
  hyperthreading: Enabled (4)
  name: master
  platform:
    ibm-cloud: {}
  replicas: 3
compute:  (2) (3)
- hyperthreading: Enabled (4)
  name: worker
  platform:
    ibmcloud: {}
  replicas: 3
metadata:
  name: test-cluster (1)
networking:
  clusterNetwork:
  - cidr: 10.128.0.0/14 (5)
    hostPrefix: 23
  machineNetwork:
  - cidr: 10.0.0.0/16 (6)
  networkType: OVNKubernetes (7)
  serviceNetwork:
  - 172.30.0.0/16
platform:
  ibmcloud:
    region: eu-gb (1)
    resourceGroupName: eu-gb-example-network-rg (8)
    vpcName: eu-gb-example-network-1 (9)
    controlPlaneSubnets: (10)
      - eu-gb-example-network-1-cp-eu-gb-1
      - eu-gb-example-network-1-cp-eu-gb-2
      - eu-gb-example-network-1-cp-eu-gb-3
    computeSubnets: (11)
      - eu-gb-example-network-1-compute-eu-gb-1
      - eu-gb-example-network-1-compute-eu-gb-2
      - eu-gb-example-network-1-compute-eu-gb-3
credentialsMode: Manual
publish: Internal (12)
pullSecret: '{"auths": ...}' (1)
sshKey: ssh-ed25519 AAAA... (13)

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: example.com (3)
   additionalTrustBundle: | (4)
       -----BEGIN CERTIFICATE-----
       <MY_TRUSTED_CA_CERT>
       -----END CERTIFICATE-----
   additionalTrustBundlePolicy: <policy_to_add_additionalTrustBundle> (5)

   1	A proxy URL to use for creating HTTP connections outside the cluster. The URL scheme must be http.
   2	A proxy URL to use for creating HTTPS connections outside the cluster.
   3	A comma-separated list of destination domain names, IP addresses, or other network CIDRs to exclude from proxying. Preface a domain with . to match subdomains only. For example, .y.com matches x.y.com, but not y.com. Use * to bypass the proxy for all destinations.
   4	If provided, the installation program generates a config map that is named user-ca-bundle in the openshift-config namespace that contains one or more additional CA certificates that are required for proxying HTTPS connections. The Cluster Network Operator then creates a trusted-ca-bundle config map that merges these contents with the 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.

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.

Manually creating IAM for IBM Cloud VPC

Installing the cluster requires that the Cloud Credential Operator (CCO) operate in manual mode. While the installation program configures the CCO for manual mode, you must specify the identity and access management secrets for you cloud provider.

You can use the Cloud Credential Operator (CCO) utility (ccoctl) to create the required IBM Cloud VPC resources.

Prerequisites

• You have configured the ccoctl binary.

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

Procedure

1. Edit the install-config.yaml configuration file so that it contains the credentialsMode parameter set to Manual.

   Example install-config.yaml configuration file

   apiVersion: v1
   baseDomain: cluster1.example.com
   credentialsMode: Manual (1)
   compute:
   - architecture: amd64
     hyperthreading: Enabled

   1	This line is added to set the credentialsMode parameter to Manual.

2. To generate the manifests, run the following command from the directory that contains the installation program:

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

3. From the directory that contains the installation program, obtain the OKD release image that your openshift-install binary is built to use:

   $ RELEASE_IMAGE=$(./openshift-install version | awk '/release image/ {print $3}')

4. Extract the CredentialsRequest objects from the OKD release image:

   $ oc adm release extract --cloud=ibmcloud --credentials-requests $RELEASE_IMAGE \
       --to=<path_to_credential_requests_directory> (1)

   1	The directory where the credential requests will be stored.

   This command creates a YAML file for each CredentialsRequest object.

   Sample CredentialsRequest object

     apiVersion: cloudcredential.openshift.io/v1
     kind: CredentialsRequest
     metadata:
       labels:
         controller-tools.k8s.io: "1.0"
       name: openshift-image-registry-ibmcos
       namespace: openshift-cloud-credential-operator
     spec:
       secretRef:
         name: installer-cloud-credentials
         namespace: openshift-image-registry
       providerSpec:
         apiVersion: cloudcredential.openshift.io/v1
         kind: IBMCloudProviderSpec
         policies:
         - attributes:
           - name: serviceName
             value: cloud-object-storage
           roles:
           - crn:v1:bluemix:public:iam::::role:Viewer
           - crn:v1:bluemix:public:iam::::role:Operator
           - crn:v1:bluemix:public:iam::::role:Editor
           - crn:v1:bluemix:public:iam::::serviceRole:Reader
           - crn:v1:bluemix:public:iam::::serviceRole:Writer
         - attributes:
           - name: resourceType
             value: resource-group
           roles:
           - crn:v1:bluemix:public:iam::::role:Viewer

5. If your cluster uses cluster capabilities to disable one or more optional components, delete the CredentialsRequest custom resources for any disabled components.

   Example credrequests directory contents for OKD 4.12 on IBM Cloud VPC

   0000_26_cloud-controller-manager-operator_15_credentialsrequest-ibm.yaml (1)
   0000_30_machine-api-operator_00_credentials-request.yaml (2)
   0000_50_cluster-image-registry-operator_01-registry-credentials-request-ibmcos.yaml (3)
   0000_50_cluster-ingress-operator_00-ingress-credentials-request.yaml (4)
   0000_50_cluster-storage-operator_03_credentials_request_ibm.yaml (5)

   1	The Cloud Controller Manager Operator CR is required.
   2	The Machine API Operator CR is required.
   3	The Image Registry Operator CR is required.
   4	The Ingress Operator CR is required.
   5	The Storage Operator CR is an optional component and might be disabled in your cluster.

6. Create the service ID for each credential request, assign the policies defined, create an API key in IBM Cloud VPC, and generate the secret:

   $ ccoctl ibmcloud create-service-id \
       --credentials-requests-dir <path_to_credential_requests_directory> \ (1)
       --name <cluster_name> \ (2)
       --output-dir <installation_directory> \
       --resource-group-name <resource_group_name> (3)

   1	The directory where the credential requests are stored.
   2	The name of the OKD cluster.
   3	Optional: The name of the resource group used for scoping the access policies.

   If your cluster uses Technology Preview features that are enabled by the TechPreviewNoUpgrade feature set, you must include the —enable-tech-preview parameter. If an incorrect resource group name is provided, the installation fails during the bootstrap phase. To find the correct resource group name, run the following command: $ grep resourceGroupName <installation_directory>/manifests/cluster-infrastructure-02-config.yml

Verification

• Ensure that the appropriate secrets were generated in your cluster’s manifests directory.

Deploying the cluster

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.

Procedure

• Change to the directory that contains the installation program and initialize the cluster deployment:

  $ ./openshift-install create cluster --dir <installation_directory> \ (1)
      --log-level=info (2)

  1	For <installation_directory>, specify the location of your customized ./install-config.yaml file.
  2	To view different installation details, specify warn, debug, or error instead of info.

  If the cloud provider account that you configured on your host does not have sufficient permissions to deploy the cluster, the installation process stops, and the missing permissions are displayed.

Verification

When the cluster deployment completes successfully:

• The terminal displays directions for accessing your cluster, including a link to the web console and credentials for the kubeadmin user.

• Credential information also outputs to <installation_directory>/.openshift_install.log.

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 link: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 xvzf <file>

4. Place the oc binary in a directory that is on your PATH.

   To check your PATH, execute the following command:

   $ echo $PATH

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 link: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

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 link: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

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

Additional resources

• Accessing the web console

Additional resources

• About remote health monitoring

Next steps

• Customize your cluster.

• If necessary, you can opt out of remote health reporting.