How to connect to OpenShift Container Platform 4.x Cluster nodes using ssh bastion pod?

Environment

• Red Hat OpenShift Container Platform
  • 4.x

Issue

• How to connect to OpenShift Container Platform 4.x Cluster nodes when they do not have external public IP?
• How to connect to OpenShift Container Platform 4.x Cluster nodes from local machine?

Resolution

• This method greatly utilizes the automation scripts present Content from github.com is not included.here. In order to connect to Openshift Container Platform 4 nodes, you need to follow given steps:

• Login to Cluster

• Create a file called 00-master-ssh-update-02.yaml with following content

apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
metadata:
  labels:
    machineconfiguration.openshift.io/role: master
  name: 00-master-ssh-02
spec:
  config:
    passwd:
      users:
      - name: core
        sshAuthorizedKeys: |
          <<ssh-public rsa key goes here>>

• Create the MachineConfig using command

oc create -f 00-master-ssh-update-02.yaml

• Create bastion ssh pod

curl https://raw.githubusercontent.com/eparis/ssh-bastion/master/deploy/deploy.sh | bash

• The status of machineconfiguration of nodes should be Done

$ oc describe node|grep machineconfig
                    machineconfiguration.openshift.io/currentConfig: rendered-worker-634a6b83277b055e4375b3c8b417fe06
                    machineconfiguration.openshift.io/desiredConfig: rendered-worker-634a6b83277b055e4375b3c8b417fe06
                    machineconfiguration.openshift.io/state: Done
                    machineconfiguration.openshift.io/currentConfig: rendered-master-6531d86976435f6bffbec9593cf47f52
                    machineconfiguration.openshift.io/desiredConfig: rendered-master-6531d86976435f6bffbec9593cf47f52
                    machineconfiguration.openshift.io/state: Done
                    machineconfiguration.openshift.io/currentConfig: rendered-master-6531d86976435f6bffbec9593cf47f52
                    machineconfiguration.openshift.io/desiredConfig: rendered-master-6531d86976435f6bffbec9593cf47f52
                    machineconfiguration.openshift.io/state: Done
                    machineconfiguration.openshift.io/currentConfig: rendered-worker-634a6b83277b055e4375b3c8b417fe06
                    machineconfiguration.openshift.io/desiredConfig: rendered-worker-634a6b83277b055e4375b3c8b417fe06
                    machineconfiguration.openshift.io/state: Done
                    machineconfiguration.openshift.io/currentConfig: rendered-worker-634a6b83277b055e4375b3c8b417fe06
                    machineconfiguration.openshift.io/desiredConfig: rendered-worker-634a6b83277b055e4375b3c8b417fe06
                    machineconfiguration.openshift.io/state: Done
                    machineconfiguration.openshift.io/currentConfig: rendered-master-6531d86976435f6bffbec9593cf47f52
                    machineconfiguration.openshift.io/desiredConfig: rendered-master-6531d86976435f6bffbec9593cf47f52
                    machineconfiguration.openshift.io/state: Done

• Get the ssh.sh script locally to be able to connect to the nodes

curl -L -O https://raw.githubusercontent.com/eparis/ssh-bastion/master/ssh.sh &&
chmod +x ssh.sh

• Connect to any of the nodes of your cluster using command

./ssh.sh ip-10-xyz.compute.internal

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