On Wed, Nov 04, 2009 at 11:15:59PM +0100, David Ulrich wrote:
> >I'm trying to get some access to a SAN mounted space elsewhere to
> >test, so I can debug it further, should know later today if I can get
> >access.
Ok, I've reproduced it now. kpartx is picking the wrong starting device and
offset for extended partitions. Looks like it's starting from sda4 but calling
it dm-2.

# sfdisk -qL -d /dev/sda 
# partition table of /dev/sda
unit: sectors
/dev/sda1 : start=      128, size=   524288, Id=83, bootable
/dev/sda2 : start=   524416, size= 10485760, Id=83
/dev/sda3 : start= 11010176, size=1453828654, Id= 5
/dev/sda4 : start=        0, size=        0, Id= 0
/dev/sda5 : start= 11010239, size= 50331713, Id=82
/dev/sda6 : start= 61342015, size=1403496815, Id=8e

# kpartx  -l /dev/sda
sda1 : 0 524288 /dev/sda 128
sda2 : 0 10485760 /dev/sda 524416
sda3 : 0 1453828654 /dev/sda 11010176
sda5 : 0 50331713 /dev/dm-2 63
sda6 : 0 1403496815 /dev/dm-2 50331839

# cat /proc/partitions
major minor  #blocks  name

   8     0  732421120 sda
   8     1     262144 sda1
   8     2    5242880 sda2
   8     3          1 sda3
   8     5   25165856 sda5
   8     6  701748407 sda6
 253     0    5242880 dm-0
 253     1    5242880 dm-1
 253     2   20971520 dm-2
 253     3    5242880 dm-3
 253     4   52428800 dm-4



-- 
Robin Hugh Johnson
Gentoo Linux: Developer, Trustee & Infrastructure Lead
E-Mail     : robbat2@gentoo.org
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