Do you remember the duplicated UID issue on RHEV 3.0? With v3.0 you can register multiple hosts with the same UUID but you can’t perform a live migration.

On RHEV 3.1 you cannot register more than one host with a specific UUID.

This means that you need to change it on each host before registering it to your RHEV Manager.

How to solve this situation? You can simply generate a new UUID by executing this command:

# uuidgen > /etc/vdsm/vdsm.id

then restart the vdsmd service…

# service vdsmd restart

…or reboot your hypervisor.

As you can see it is no longer necessary to edit the file libvirtd.conf on each hypervisor.