Re: [linux-lvm] LVM snapshot with Clustered VG [SOLVED]

[Vladislav Bogdanov <bubble@hoster-ok.com>]

15.03.2013 21:38, David Teigland wrote:
> On Fri, Mar 15, 2013 at 08:46:53PM +0300, Vladislav Bogdanov wrote:
>> I also thought about dlm one (may be the next step :) ), 
> 
> Let me know if you decide to start work on this and I can probably lend
> some help.
> 
>> Of course, I fully agree that clvm is just a big hack from the today's
>> point of view and something need to change here.
> 
> Since you're open to hacking components together, here's another possible
> hack:  you could create a gfs2 file system on the shared storage, and use
> file locks on gfs2 files.  The gfs2 files could be the actual vm images,
> but they do not have to be.  You could still use lv's for vms directly,
> and create empty files on gfs2 representing each lv.  The virtlockd file
> locks would be acquired on the empty gfs2 files, representing the lvs.
> This is another indirect way of using dlm locks, since the gfs2 file locks
> are passed to the dlm.

That would not solve issue with exclusive LV activation which is
required to take snapshots (and just for more safety), but prevents
migration.

Vladislav