On Mar 26, 2007  14:37 -0700, Herb Wartens wrote:
> Here at LLNL we have developed a little tool called stumpy
> that also bypasses an OST without blocking.  The idea is that
> we can add in a "stump" OST in place of a damaged OST until we find
> out and fix the problem on the damaged OST.  The "stump" OST would be
> started in a read-only/deactivated state so that no new objects will
> be written to the device.  This avoids us having to go out to our
> many thousands of clients and deactivating the damaged OST on each one.
> The data in the client caches should also be safe with some new Lustre
> fixes to ensure that when an OST goes read-only the client will hold the data
> since the state is expected to be transient.
> 
> stumpy does require changes to the ldiskfs code (to allow mounting the
> filesystem in read-only mode) as well as Lustre code changes to allow
> Lustre to start in read-only mode.

Herb, could you perhaps attach the code to this thread and/or file a bug
in bugzilla with a patch and report the bug number here?  I think the
read-only OST mounting code might be welcome for other reasons also.

Cheers, Andreas
--
Andreas Dilger
Principal Software Engineer
Cluster File Systems, Inc.

_______________________________________________
Lustre-discuss mailing list
[email protected]
https://mail.clusterfs.com/mailman/listinfo/lustre-discuss

Reply via email to