our setup consists of a ubuntu 10.04 kvm host server with LVM, on top of which we install the ubuntu 10.04 virtual machines via virt-install and preseed. Each VM has a dedicated logical volume which we pass to virt-install via the "--disk path=/dev/sysvg/vm-name" parameter. The virtual machines themselves are using LVM as well.
Virt-install seems to have a few issues with this setup. Say we want to install two virtual machines in parallel. The first vm installs correctly while the second halts during the partitioning, complaining with this error: "volume group name already in use". I tried removing the logical volumes, recreated them, rebooted the kvm host to clear any leftovers but the issue perists. The preseed is telling the vms to create a volume group named "sysvg", which is the same name used by the volume group of the kvm host. Considering this I did another test: I got rid of the preseed part taking care of the partitioning/lvm creation and started the creation of two vms in parallel. If, when prompted, I instruct the vms' installer to do a guided partitioning of the disk with LVM, it will still fail giving this different error on both the vms:
Physical Volume /dev/sda5 is already in volume group sysvg.
As I wrote, sysvg is the volume group used by the KVM host. So I thought the name clashing was the issue. By removing the preseed part I skipped the volume group naming. I can't understand how the virtual machines would be aware of the presence of that volume group since they're supposed to be isolated from it, especially after I removed and recreated the logical volumes dedicated to them. That detail should not be exposed at all to them!
Thanks for the help. I'm clueless.