Lustre devel - Feb 2007 - [Bug 11672] e2fsck overwrites all superblock backups during journal replay

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https://bugzilla.lustre.org/show_bug.cgi?id=11672



Created an attachment (id=9550)
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 --> (https://bugzilla.lustre.org/attachment.cgi?id=9550&action=view)
Clear MASTER_SB_ONLY flag by default in libext2

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using the following link:
https://bugzilla.lustre.org/show_bug.cgi?id=11672

           What    |Removed                     |Added
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OtherBugsDependingO|                            |2840
              nThis|                            |


(In reply to comment #0)
> When fsck replays the journal, it clears the EXT3_FEATURE_INCOMPAT_RECOVER
> feature, dirties the superblock, and closes the file system. 
Unfortunately, the
> file system EXT2_FLAG_MASTER_SB_ONLY flag is not set at this time, so it
copies
> the primary superblock and group descriptors over all the backups.  Then
fsck
> restarts and checks the superblock for consistancy.  If the superblock or
group
> descriptors are then found to be bad, all your backups are now also bad.
Ouch, this is a major problem that deserves to be pushed upstream ASAP. 
I''ve
emailed Ted and CC''d you and ext4-devel on it.  Yet another reason to
get the
journal checksum patch going.