Subject: Re: [vserver] cluster file system and vserver
From: Martin Fick <mogulguy@yahoo.com>
Date: Tue, 15 Jul 2008 14:25:05 -0700 (PDT)

--- On Tue, 7/15/08, Edward Capriolo <edlinuxguru@gmail.com> wrote:

> >
> I have setup glusterfs between vservers. It seems to work
> well under very limited testing. I do not understand why you would
> need to run gluster ontop of  DRBD, but you probably can prove me
> wrong. I am sure there are good reasons to :)

Simple, glusterfs AFR does not prevent split brain operation.  AFR is well suited for
clusters where nodes rarely go down and can be expected to come back up before any others
go down and where network outages are very unlikely.  Glusterfs AFR really is a very
simplistic node replication algorithm that is meant more for providing high availability
but it does not yet ensure consistent data.  If you have lots of disks and can do AFR
with several copies (more than 2) than it might be safer, but that might also kill you
performance.  Search or ask on the glusterfs mailing list if you want to know more why
AFR might not be a good idea for this.

-Martin