[libvirt-users] How to find out what is deleting my vms

Hi, I have a CentOS-7 server running KVM but also oVirt. Recently, following updates, VMs not handled by oVirt have been deleting themselves after they shut down. Previously to this, I have not had any problems of this nature. I cannot say whether the problem is coming from oVirt updates or not. I am creating a VM using "virsh define myvm.xml" on the server, starting it through virt-manager on my local PC, performing work inside the VM and then closing down the operating system inside the VM, and then once it has completed shutting down it shows "Shutoff" as the status in virt-manager and then maybe 5 seconds later it disappears from the list entirely and has been deleted. To start the VM again, requires "virsh define myvm.xml" to be run again. What I cannot determine is **why** the VM is deleted. I am using "virsh define" which I understand should create a persistent VM, and I have enabled "audit_level=2" and "audit_logging=1" in libvirtd.conf but can't see anything helpful in the log output (although maybe I don't know what I'm looking for). Is anyone, please, able to help me work out what is deleting my VMs once they shut down ... and, if possible, why?! Many, many thanks, Andy