Following from SPM-3729, shards will authoritatively own the DB metadata. We have also updated the check metadata consistency command to check for any inconsistency between various metadata stores (config server and shards) and the relevant caches.

What if we find an inconsistency or need a way to manipulate the metadata for maintenance?

This ticket will brainstorm the scenarios we might encounter, code any needed changes to the server, and write a maintenance playbook.

[Note: Also consider the future projects that will make the collection metadata authoritative as well.]