ZFS: can't read MOS of pool

[Trond Endrestøl]

On Fri, 2 Aug 2013 17:04+0200, ?ukasz W?sikowski wrote:

> W dniu 2013-07-25 22:23, Trond Endrestøl pisze:
> 
> > Perhaps you should reset the mountpoint property for klawisz, using:
> > 
> > zfs set mountpoint=legacy klawisz
> > 
> > At the same time you may let klawisz/ROOTFS inherit the mountpoint 
> > property from klawisz by running:
> > 
> > zfs inherit mountpoint klawisz/ROOTFS
> 
> Thank you for you reply. I did what you've suggested, now I'm getting:
> 
> ZFS: i/o error - all block copies unavailable
> ZFS: can't read object set for dataset u
> ZFS: can't open root filesystem
> gptzfsboot: failed to mount default pool klawisz
> 
> Those KVM VMs are very stubborn with this "I won't boot" attitude ;)

Could there be a bug in the underlying storage system?
What filesystem does the VM's virtual harddrives reside on?
Could the physical storage media be corrupt?

For some reason ZFS expects additional (leaf) vdevs to be present. 
I've seen similar error messages when an insufficient number of drives 
were not made visible by the boot firmware, i.e. BIOS.

If this VM is important, you should make a snapshot, or make a copy, 
if you have enough free space.

And it might be best to seek advice from someone more versed with the 
internals of ZFS than I am. :-/

-- 
+-------------------------------+------------------------------------+
| Vennlig hilsen,               | Best regards,                      |
| Trond Endrestøl,              | Trond Endrestøl,                   |
| IT-ansvarlig,                 | System administrator,              |
| Fagskolen Innlandet,          | Gjøvik Technical College, Norway,  |
| tlf. mob.   952 62 567,       | Cellular...: +47 952 62 567,       |
| sentralbord 61 14 54 00.      | Switchboard: +47 61 14 54 00.      |
+-------------------------------+------------------------------------+