[libvirt] FYI, "Unable to create cgroup for ..."

In case someone else encounters this... Today none of my VMs would start on F15: # virsh create rawhide.xml error: Failed to create domain from rawhide.xml error: Unable to create cgroup for rawhide: No such file or directory Luckily, I noticed that Rich Jones had the same problem a week ago and he found that restarting libvirtd was enough to solve the problem: # service libvirtd restart That did it for me, too.