TripleO backup and restore (Undercloud and Overcloud control plane)

This documentation section will describe a method to backup and restore both Undercloud and Overcloud control plane.

The use case involved in the creation and restore of these procedures are related to the possible failures of a minor update or major upgrade for both Undercloud and Overcloud.

The general approach to recover from failures during the minor update or major upgrade workflow is to fix the environment and restart services before re-running the last executed step.

There are specific cases in which rolling back to previous steps in the upgrades workflow can lead to general failures in the system, i.e. when executing yum history to rollback the upgrade of certain packages, the dependencies resolution might select to remove critical packages like systemd.