create a q35+seabios cluster create vm run once, do not change anything other than attaching a CD and boot from it run power down run again using the regular Run fails to run, complaining on "bus must be 0 for ide controller" The VM was created as i440fx during RunOnce, and then it fails when it start normally since the cluster setting will set the VM to q35 Same happens with RunOnce and checking "Rollback this configuration during reboots ", the VM fails to come up after a reboot.
This is probably fixed in BZ 1770697. I couldn't managed to reproduce after the first patch of the above bug went in. Closing as a duplicate. *** This bug has been marked as a duplicate of bug 1770697 ***