[CentOS-virt] RAID: by host or within KVM?

Fri Aug 10 15:00:06 UTC 2012
Stephen Harris <lists at spuddy.org>

On Fri, Aug 10, 2012 at 10:39:18AM -0400, Kanwar Ranbir Sandhu wrote:
> 1. Let the KVM host manage the drives (i.e. RAID with LVM on top) and just
> assign the single volume to OMV. OMV will see it as one HD.
> 2. Assign the individual drives to the OMV KVM, and let OMV manage the
> creation, management, etc. 

I recommend option 1 simply because of recovery methodology.  If you
lose a disk and replace it, if the host controls the RAID then you have
one point of repair and the VMs don't even notice.  If, however, each
VM does RAID itself then _each_ VM will need to perform disk replace
and rebuild, which is a lot of admin overhead.  Also that could cause
a lot of disk contention and slow down the rebuild.

Today you only have one VM.  Tomorrow? :-)