Setting up KVM guests with DRBD block device for storage using vmbuilder or virt-manager

[Hans Vos]

On 06/11/2012 01:41 AM, Hans Vos wrote:
> I've been working all weekend on getting this work but I can't find any
> good documentation or tutorials for creating KVM guests using DRBD block
> devices for storage. My setup consists of two identical servers with
> Ubuntu 12.04. I have successfully installed them and configured my
> network bridge and DRBD block device.
>
> Here are some outputs of my configuration:
>
> - ifconfig: http://paste.ubuntu.com/1034662/
> - lvdisplay: http://paste.ubuntu.com/1034666/
> - brctl show: http://paste.ubuntu.com/1034667/
> - cat /proc/drbd: http://paste.ubuntu.com/1034672/
>
> Ideally I would like to be able to create a new KVM guests using
> virt-manager on my Ubuntu desktop machine. This way I can install the
> KVM quest like I would normally install a server. I can setup the
> connection but I have no idea how to configure the storage pool to make
> use of the DRBD device (/dev/drbd0) or how to make use of my network
> bridge. It defaults to NAT networking. But using vmbuilder tool would be
> acceptable also. I have followed several tutorials but none of them
> cover the use of a DRBD block device for storage.
>
> How can I get this to work? Do I maybe have to setup an LVM layer on top
> of my DRBD device and add that to the libvirt storage pool
> configuration? What kind of command should I run to try to get vmbuilder
> to create a KVM guest with my DRBD block device?
>
> Over a year ago I tried setting up a Xen guest under CentOS using a DRBD
> block device by following the DRBD documentation
> (http://www.drbd.org/users-guide/ch-xen.html). I have no idea why this
> is so much harder with KVM. Since both CentOS and Ubuntu have switched
> to KVM and Ubuntu is my distribution of choice I would like to setup
> something similar using Ubuntu.

I managed to get the setup working I was looking for and written a 
tutorial for other people to use. Any feedback on the tutorial is 
greatly appreciated.

http://www.bluejay.nl/2012/06/23/simple-manual-failover-cluster-with-drbd-lvm-and-kvm-on-ubuntu-12-04-precise-pangolin/

--
Kind regards,

Hans Vos