On 10/18/2017 06:59 AM, d tbsky wrote: > hi: > I upgrade my system from rhel 7.3 to 7.4. so libvirt upgrade to 3.2. > > I found command "virsh define vm.xml" sometimes modify "vm.xml". That command would only modify the file "vm.xml" if it was located in /etc/libvirt/qemu (or /etc/libvirt/lxc, or whatever was appropriate for the domain type) *and* the domain's <name> happened to be "vm". If that's what's happening, this email should be your warning to never directly modify or access the files in /etc/libvirt; they are files used internally by libvirt, and modifying them can lead to "unexpected" results.