[Ocfs2-users] Could several different ocfs2 volume share a same lockspace?

[Goldwyn Rodrigues]

On 05/04/2016 12:43 AM, Eric Ren wrote:
> Hello,
>
> As email subject tell, I encountered this weird problem. I got this from
> customer:
>
> # /sbin/mounted.ocfs2 -d
> Device     Stack  Cluster   UUID
> /dev/sdb                                       pcmk   pacemaker
> 032F55597DEA4A61AB065568F964174D
> /dev/sdal                                      pcmk   pacemaker
> 032F55597DEA4A61AB065568F964174D
> /dev/sdau                                      pcmk   pacemaker
> 032F55597DEA4A61AB065568F964174D
> /dev/sdbd                                      pcmk   pacemaker
> 032F55597DEA4A61AB065568F964174D
> /dev/sdbv                                      pcmk   pacemaker
> 032F55597DEA4A61AB065568F964174D
> /dev/sdce                                      pcmk   pacemaker
> 032F55597DEA4A61AB065568F964174D
> /dev/sdcw                                      pcmk   pacemaker
> 032F55597DEA4A61AB065568F964174D
> /dev/sdcn                                      pcmk   pacemaker
> 032F55597DEA4A61AB065568F964174D
> /dev/mapper/3600507640081010d5000000000000082  pcmk   pacemaker
> 032F55597DEA4A61AB065568F964174D
>
> I'm surprised several different ocfs2 volumes have the same UUID, and
> DLM use disk UUID as lockspace's name which means they share same lockspace!
>
> Did you ever see this? Is it possible for different volumes share same
> lockspace? why?
>

Two possiblities:

1. Multipathing
2. User replicated the disk image.

Otherwise no. Not possible (in the limits of pseudo-randomizations)

-- 
Goldwyn