Re: [Xen-users] Xen and iSCSI

[Pasi Kärkkäinen <pasik@xxxxxx>]

On Sun, Jan 29, 2006 at 03:11:54PM +0100, Markus Hochholdinger wrote:
> Hi,
> 
> Am Sonntag, 29. Januar 2006 15:02 schrieb Pasi Kärkkäinen:
> [..]
> > Wouldn't it be better to use iSCSI initiator in dom0, and map luns from two
> > different storage servers (and SANs).. raid1 them, and create LVM (or CLVM)
> > on top of raid.. and export LV to each domU.
> 
> define better!? It is easier to set up. But if you want to use migration it 
> becomes complicatet. If you use more than one Xen host you have to setup on 
> each Xen host the block devices (iscsi, raid, lvm). And i'm not sure what 
> happens if you have two active raid1 on the same iscsi devices on different 
> Xen hosts!?
>

CLVM (Cluster LVM) is supposed to handle this.. it allows to create volumes
to shared storage (FC, iSCSI, etc).

And Xen itself handles the migration.. access to block device on host1 is
stopped when the access is started on host2 (after the migration). 
 
> 
> > Then you could more easily upgrade the storage servers and only rebuild the
> > raid in dom0.. domU's wouldn't see any problems / failures.
> 
> Well, rebuild will take the same amount of network traffic. I'm not sure if 
> it 
> is really better?
> My idea is to have the domU not depend on the block device configuration of 
> dom0. So its easier to migrate domUs.
> 

Personally I'd like to keep all the raid/iscsi stuff out of domU's.. to keep
domU's simple and easy to manage :)

-- Pasi

_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-users