Hi!
I'm sorry, but I dont know, how to help you. We move OSDs from XFS to EXT4 on our test
cluster (Hammer 0.94.2), removing ODSs one-by-one and re-adding them after reformatting
to EXT4. This process is usual to a ceph (Add/Remove OSDs in documentaion) and took
place without any data loss. We also change ruleset, like written in Sebastian Han's blog:
http://www.sebastien-han.fr/blog/2014/08/25/ceph-mix-sata-and-ssd-within-the-same-box/And it was also with no harm to data. But we dont use tiering, maybe some things
happens with data while removing cache tier, like not all objects was written back to
lower lier pool?
Megov Igor
CIO, Yuterra