[LU-4487] LFSCK 5: modify Lustre with backend mounted directly and keep system consistency

Sun, 30 Jan 2022 10:53:11 +0000

There are some remaining issues for the following patch to be further discussed and resolved:

http://review.whamcloud.com/#/c/8002/

In fact, there are some rude usages for Lustre admin to modify Lustre with ldiskfs mounted directly, which may cause some stale OI mapping entries left in the OI files but related inodes have been removed. Sometimes, such modification are meaningful. For example: removing last_rcvd file to resolve some recovery trouble; removing OI files to increase OI files count for larger scale or shrink OI files unused space; and so on. On the other hand, such modification brings trouble to the system consistency. Currently, we use OI scrub to resolve those trouble as much as possible. But is seems not the best solution. Maybe we can introduce more suitable way to resolve the issues in the future. For example, we can offer a offline tools set to admin to modify Lustre files and related OI mappings together, then guarantee that even though the modification is done under ldiskfs mounted, the system is still is consistent.

Whamcloud Community JIRA

[LU-4487] LFSCK 5: modify Lustre with backend mounted directly and keep system consistency