[OmniOS-discuss] r151014 users - beware of illumos 6214 - steps to check and repair...

[Guenther Alka]

What is the recommended action on OmniOS 151014 about the L2Arc Problem

1. what is the recommended way to detect possible problems
   a. run scrub? seems useless
   b. run zdb pool and check for what
      You said:  Look for assertion failures, or other non-0 exits. Is 
this the key for a corrupt pool?

2. when using an L2Arc and there is no obvious error detected by scrub 
or zdb
   a. trash the pool and restore from backup  via rsync with possible 
file corruptions but ZFS structure is 100% ok then
   b. keep the pool and hope that there is no metadata corruption?
   c. some action to verify that at least the pool is ok: ....

3. when using an L2Arc and there is an error detected by scrub or zdb
   a. trash the pool and restore from backup with possible file 
corruption but pool is 100% ok
   b. keep the pool and hope that there is no metadata corruption
   c. some action to verify that at least the pool is ok: ....

Is there an alert page at OmniOS wiki about?

Gea


Am 10.09.2015 um 13:53 schrieb Dan McDonald:
> If you are using a zpool with r151014 and you have an L2ARC ("cache") vdev, I recommend at this time disabling it.  You may disable it by uttering:
>
> 	zpool remove <pool-name> <cache-vdev-name>
>
> For example:
>
> 	zpool remove data c2t2d0
>
> The bug in question has a good analysis here:
>
> 	https://www.illumos.org/issues/6214
>
> This bug can lead to problems ranging from false-positives on zpool scrub all the way up to actual pool corruption.
>
> We will be updating the package repo AND the install media once 6214 is upstreamed to illumos-gate, and pulled back into the r151014 branch of illumos-omnios.  The fix is undergoing some tests from ZFS experts right now to verify its correctness.
>
> So please disable your L2ARC/cache devices for maximum data safety.  You can add them back after we update r151014 by uttering:
>
> 	zpool add <pool-name> cache <cache-vdev-name>
>
> PLEASE NOTE the "cache" indicator when you add back.  If you omit this, the vdev is ADDED to your pool, an operation one can't reverse.
>
> 	zpool add data cache c2t2d0
>
> Thanks,
> Dan
>
> _______________________________________________
> OmniOS-discuss mailing list
> OmniOS-discuss at lists.omniti.com
> http://lists.omniti.com/mailman/listinfo/omnios-discuss