When new versions of OKD are released, you can upgrade your existing cluster to apply the latest enhancements and bug fixes. For OpenShift Origin, see the Releases page on GitHub to review the latest changes.
Unless noted otherwise, node and masters within a major version are forward and backward compatible across one minor version, so upgrading your cluster should go smoothly. However, you should not run mismatched versions longer than necessary to upgrade the entire cluster.
There are two methods for performing OKD cluster upgrades. You can either do in-place upgrades (automated or manual), or upgrade using a blue-green deployment method.
With in-place upgrades, the cluster upgrade is performed on all hosts in a single cluster. If you installed using the advanced installation and the ~/.config/openshift/installer.cfg.yml or inventory file that was used is available, you can perform an automated in-place upgrade. Alternatively, you can upgrade in-place manually.
With blue-green deployments, you can reduce downtime caused while upgrading an environment by creating a parallel environment on which the new deployment can be installed. If a problem is detected, and after the new deployment is verified, traffic can be switched over with the option to rollback.