[ceph-users] Best way to change bucket hierarchy

Helo, I have a live ceph cluster, and I’m in the need of modifying the bucket hierarchy. I am currently using the default crush rule (ie. keep each replica on a different host). My need is to add a “chassis” level, and keep replicas on a per-chassis level. From what I read in the documentation, I would have to edit the crush file manually, however this sounds kinda scary for a live cluster. Are there any “best known methods” to achieve that goal without messing things up? In my current scenario, I have one host per chassis, and planning on later adding nodes where there would be >1 hosts per chassis. It looks like “in theory” there wouldn’t be a need for any data movement after the crush map changes. Will reality match theory? Anything else I need to watch out for? Thank you! George