- Once you want to take snapshot on storage, the client should flush its filesystem cache before the snapshot taken, otherwise the snapshot will be inconsistent and may not include desired data. The correct order of commands will be : “sync ; snap create” .
- NEVER do snapshot revert on mounted file system as shown in course example. The correct order is : " umount ; snap revert ; mount" . Otherwise you can finish with kernel oops about corrupted file system.
These recommendations are not related to CEPH, but for any SAN mounts.