Hi, 1) Thank you all for the official support of the AMD EPYC processors in version 4.3! :-) 2) During the upgrade process I removed the old guest ISO file and replaced it with the new one (different filename of course). As I moved a virtual machine with the old ISO file mounted, the vm crashed. "Migration failed: Lost connection with qemu process (VM: <vmname>, Source: <ovirt-node-host>)." Yes I know this is not real bug (dumb user), but maybe it is good preventing the users for doing something stupid ;-) 3) The log contains following messages after upgrading the node: "VDSM <ovirt-node-host> command Get Host Statistics failed: Internal JSON-RPC error: {'reason': '[Errno 19] genev_sys_6081 is not present in the system'}" This stops after some time ~20-30 minutes, but comes back after a restart of a node. And disappears again after some time. At the moment we have no problems and not taking this as a real issue. 4) If we are running Windows 10 guests newer than build version 1709, the vm crashes on our EPYC cluster, on the SandyBridge cluster the issue doesn't exists. The reason is the wrong CPU model of QEMU, see: <https://bugzilla.redhat.com/show_bug.cgi?id=1593190> We fixed this problem with a line in "/etc/modprobe.d/kvm.conf" "options kvm ignore_msrs=1". Thank you all for this great piece of software :-) Regard Tobias