Kernel panic importing a pool.

[sean.nutech]

I am working with someone to recover a freenas system that is kernel has a kernel panic.

The system when it imports the pool has the attached panic running freenas 8.0.4 p2

I have also tried to import the volume using openindiana ( Solaris ) with a similar error.


This page shows a similar error and may be a fix but we are not sure of the best approach to take to fix the disk.

http://sigtar.com/2009/10/19/opensolaris-zfs-recovery-after-kernel-panic/

The system is a single disk presented to freenas but is actually 12 disks in a hardware raid 6. The disks seems healthy
according to the adaptec raid card.

Any suggestions are welcome.

Re
Sean M

 

[jpaetzel]

Reboot the system, at the boot menu select the option to drop to the loader prompt.

At the loader prompt type:

set vfs.zfs.recover=1
set vfs.zfs.debug=1
boot -s

Once you are in single user mode do:

zpool import -R /mnt poolname

If that fails, do it all again with zpool import -FR /mnt poolname

If that fails, do it all again with zpool import -XFR /mnt poolname

Running a scrub after the import is highly recommended.

If this doesn't help the pool is toast.

 

[sean.nutech]

According the the person with the array It is not recognizing the -"X" or "F" args under FN8

Is this only for a later release of FN?


Re
Sean M

 

[jpaetzel]

Ah right, you need ZFS v28 for that which FreeNAS doesn't have. Boot a FreeBSD 9 CD and try the import there.

 

[icubedajb]

I just want to follow-up on this issue. In order to recover the pool, I executed the following: I am not sure how much of it was required. This may be beneficial to the next person. As a note, I was not able to recover the pool with FreeBSD 9 CD. I had to use Solaris 11 live CD.

1. Boot to Solaris 11 live CD.
2. Change to the root user.
3. Change the name of the live image to match the hostname and domain of the failed server environment.
4. Set zfs:zfs_recover=1
5. Set aok=1
6. Added the same configuration to the /etc/system file.
7. Verified the pool was online by typing zpool import {Pool was online}
8. Just for grins, try various combinations of zpool import {fFXR} /mnt but all kernel panic'ed.
9. Ran the following command as specified by this website: http://sigtar.com/2009/10/19/opensolaris-zfs-recovery-after-kernel-panic/
-----> zdb -e -bcsvL <poolname> NOTE: This error-ed out with an out of memory error after some time had expired. Initially 15 minutes. But I ran this same command at least 3-4 times more and each time, the out of memory error occurred later. The last run was around an hour before experiencing the error.
10. Retried the import command again {again for grins}. The command used: zpool import -rfFXR /mnt <poolname>. After a few minutes, it mounted. There are a few virtual environments which appear to have corrupted data but compared to what I retrieved, it paled in comparison.

I do want to thank Sean {although he is ignoring all my emails now :) } and jpaetzel for getting me to this point.