I have a KVM+LibVirt based hypervisor running on Fedora 22. I use virt-manager for managing the VMs over SSH.
For some reason I see "guestfs-00kxipwaewnkoq92" VMs appearing and disappearing at random. They generally don't exist longer than 10-20 seconds, so it's hard to inspect them, but I do know they don't have a VNC/Spice connection available for viewing.
Searching google for "guestfs- libvirt" and "guestfs virt-manager" doesn't yield and useful results. Does anyone know what these guestfs-xxxxxxxx VMs are and what their purpose is? Thanks!