[Lustre-discuss] Multiply claimed blocks

[Andreas Dilger]

On 2010-04-14, at 09:59, Dan wrote:
> After an OSS crashed I ran fsck and all but one OST returned quickly
> after fixing a few errors.  It's been duplicated multiply claimed  
> blocks
> for a few days now.  Seems it's a very slow and CPU bound operation.
> Are there other ways to fix or replace this OST?
>
> I'm running on RHEL 4 w/ latest Lustre e2fsprogs.  Thanks for any
> suggestions!


Do you mean RHEL5.4?

The Lustre-patched e2fsck has a feature that can simply discard inodes  
that have shared blocks.  This is a potential concern in secure  
environments when it is unclear which inode the original file data  
belongs to.  A new e2fsck option:

-E shared=preserve|lost+found|delete

     Select the disposition of files containing shared blocks.   
"preserve"
     is the old behavior which remains the default.  "lost+found" causes
     files to be unlinked after cloning so they will be reconnected to
     /lost+found in pass 3.  "delete" skips cloning entirely and simply
     deletes the files.

You probably want to use the "-E shared=delete" option.

Cheers, Andreas
--
Andreas Dilger
Principal Engineer, Lustre Group
Oracle Corporation Canada Inc.