When upgrading your OKD cluster, there are two primary data
migrations that take place. The first occurs while still running the current
version of OKD, and the second happens after the upgrade completes.
If the pre-upgrade migration fails, the upgrade will be halted and the cluster
administrator must resolve any data consistency problems before attempting the
upgrade again. If the post-upgrade migration fails, the upgrade will complete
and the cluster administrator should investigate the data migration issues as
soon as possible. This document catalogs known data consistency problems and how
to resolve them.