Successfully upgrade OpenShift cluster on a disconnected environment with troubleshooting guide.

With the frequent new releases of OpenShift versions, it is important that we stay up-to-date with the latest version. As per the Red Hat article https://access.redhat.com/support/policy/updates/openshift#:~:text=Red%20Hat%20forecasts%20OpenShift%20for,Full%20Support%20and%20Maintenance%20Support, the below table shows that the frequency of new release versions is typically 3 months.

OpenShift Container Platform upgrade is supported on the following environments :

1. Disconnected environment: This environment does not have internet connectivity. These are also referred to as a restricted or airgap environment. A private docker registry is required in such environments where the images can be mirrored to and pulled from.

2. Online environment: The environment which has internet connectivity. In this case, the images will be pulled directly from the online registry.

The blog lists down the steps to upgrade an existing cluster in a disconnected environment. Upgrading a cluster helps to apply the latest enhancements and bug fixes available in…