Ceph » devops

As an admin, I want to move an OSD data disk from one physical host (chassis) to another (e.g. for maintenance of non-hotswap power supply).
I might have a single SSD, divided into multiple partitions, each acting as the journal for a single OSD data disk. I want to spread the load evenly across the rest of the cluster, so I move the OSD data disks to multiple destination machines, as long as they have 1 slot free. Naturally, I cannot easily saw the SSD apart and move it physically.

I would like to be able to:

1. shut down the osd daemon
2. explicitly flush out & invalidate the journal on SSD (after this, the journal would not be marked with the osd id and fsid anymore)
3. move the HDD
4. on the new host, assign a blank SSD partition and initialize it with the right fsid etc metadata

It may actually be nicer to think of this as:

1. shut down the osd daemon
2. move the journal inside the osd data dir, invalidate the old one (flushing it is an optimization)
3. physically move the HDD
4. move the journal from inside the osd data dir to assigned block device