Il 20-08-2017 09:14 Mikael Abrahamsson ha scritto:
After a non-clean poweroff and possible mismatch now between the RAID1 drives, and now fsck runs. It reads from the drives and fixes problem. However because the RAID1 drives contain different information, some of the errors are not fixed. Next time anything comes along, it might read from a different drive than what fsck read from, and now we have corruption.
It can be even worse: if fsck reads from the disks with corrupted data and tries to repair based on these corrupted information, it can blow up the filesystem completely.
In my case, heavy XFS corruption was prevented by the journal metadata checksum, which detected a corrupted journal and stopped mounting. However, some minor corruption found their ways onto the dentry/inode structures.
Being a backup machine, this was not a big deal, as I simply recreated the filesystem from scratch. However, the failure mode (synced writes which were corrupted) was quite scary.
Regards. -- Danti Gionatan Supporto Tecnico Assyoma S.r.l. - www.assyoma.it email: g.danti@xxxxxxxxxx - info@xxxxxxxxxx GPG public key ID: FF5F32A8 -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html