disklabel and gm0 (gmirror)

[hv]

Am 09.04.2008 um 00:33 schrieb Miroslav Lachman:
> Ferruccio Zamuner wrote:
>
>> # disklabel /dev/mirror/gm0
>> # /dev/mirror/gm0:
>> 8 partitions:
>> #        size   offset    fstype   [fsize bsize bps/cpg]
>> a:  2089984       79    4.2BSD        0     0     0
>> b:  2910000  2090063    unused        0     0        c:  
>> 463459122       63    unused        0     0         # "raw" part,  
>> don't edit
>> d: 10000000  5000063    4.2BSD        0     0     0
>> e: 10000000 15000063    4.2BSD        0     0     0
>> f: 15000000 25000063    4.2BSD        0     0     0
>> g: 423459058 40000063    4.2BSD        0     0     0
>> partition c: partition extends past end of unit
>> disklabel: partition c doesn't start at 0!
>> disklabel: partition c doesn't cover the whole unit!
>> disklabel: An incorrect partition c may cause problems for standard  
>> system utilities
>> ...
>
> Backup all your data (if gm0 is not empty) and start with new  
> standard label:
> bsdlabel -w /dev/mirror/gm0
> Then open the label for editing:
> bsdlabel -e /dev/mirror/gm0
> and add you new partitions, but don't touch the line with c: partition
> ...

why not just using gmirror to break and recreate the mirror, something  
like this:

1) remove one disk (it's a mirror!)
2) recreate the label on this disk, newfs it and  copy everything over  
from the remaining mirror disk.
3) if you booted off the mirror, you need to adjust fstab to boot from  
the disk 1) and reboot, then destroy the mirror.
4  recreate the mirror on the disk from 1), if you want to boot from  
the mirror, re-adjust the fstab and reboot
5) insert the second disk into the recreated mirror in 4)

see  gmirror(8), hope this helps.

Regards
--
Henry Vogt <hv at tuebingen.mpg.de> (Fon: ++49-7071-601-511, Fax: -826)
Campus Max-Planck-Institute, Spemannstr. 32-41, Tübingen, Germany