[Xen-users] Storage Question

Ramon Moreno
Sat, 31 Jan 2009 22:08:54 -0000

Greetings,

I am looking at iSCSI for a storage option for my vms, however I am
looking at two methods of implementation. Would appreciate feedback...
:-)

Xen Setup -
xen 3.03
CentOS 5.2
Using CLVM
Using Clustering
Using a GFS for the location of my config files

Option 1:
I present a single iscsi lun to my systems in the cluster. I then
carve it up using lvm for the vms. The problem with this solution is
that if I clone a vm, it takes mass network bandwidth. If I use some
other methods other than dd I can throttle somewhat, but I would like
to create the vms as fast if possible.

Option 2:
I present multiple iscsi luns to the systems in the cluster. I still
add to lvm so I dont have to about labeling and such. Adding to lvm
ensures things dont change with the lun on reboot. With this option I
can use the storage layer (using a netapp like solution) to clone luns
and such. This eliminates the possibility of saturating the network
interfaces when cloning vms. However, I have to rescan the target each
time I add a new vm.

I am also trying to avoid using image files to minimize impact to performance.

Wonding if anyone has any experience with these two options, and what
they did to optimize.

Thanks in advance!