Subject: Re: Xen and Raidframe
To: tls@rek.tjls.com, Geert Hendrickx <ghen@NetBSD.org>
From: Greg Oster <oster@cs.usask.ca>
List: port-xen
Date: 11/04/2006 12:18:35
Thor Lancelot Simon writes:
> On Sat, Nov 04, 2006 at 05:02:12PM +0100, Geert Hendrickx wrote:
> > On Sat, Nov 04, 2006 at 08:23:01AM -0500, Steven M. Bellovin wrote:
> > > One apparent option, for the production DOMUs, is to have matching
> > > partitions on each hard drive, and have the DOMUs do RAID themselves.  A
> > > second is to use a large DOM0 partition, with RAID, and assign a DOMu a
> > > file in that partition.  This strikes me as slower, but adequate for
> > > light-load and experimental servers.
> > 
> > The third (and I think most-used) option is to run the software RAID in the
> > dom0 and provide each domU with a block device on the RAID (e.g. raid0g).
> 
> I think this is a poor choice.  You are at the mercy of any of several kinds
> of bugs in RAIDframe which might cause it to misbehave when its strategy
> routing is called from xbd (I've seen more than one; vnd was specifically
> retooled to be safe this way)

Which bugs would these be, and do you have PR#'s?  

Thanks.

Later...

Greg Oster