For the most part, the VMs require a failover of the databases and the DNS that points to them to reduce impact to Toolforge and CloudVPS users so that we can do maintenance on the hypervisor servers. However, there is communication to be done and specific steps to take. Those will be documented here.
**ToolsDB -- clouddb1001/2**
This has unreplicated tables requiring some special efforts and additional downtime for affected tools. Two of the unreplicated databases are only temporarily so (see T257274 and T257275), which will be cleared up by this change. It is worth it to review the others to make sure they are still active and need to remain unreplicated in case we can clear more of these barriers for the future.
**OSMDB -- clouddb1003/4**
This should be a straight PostgreSQL failover.