Comment # 38 on bug 1158817 from Neil Rickert

>Granted for "ip a", but please check your own attachment in comment 16 again. Unless I'm dreaming, it says "virbr0".

Looking closely -- yes, it is there.  It seems to be defining a NAT network
with IP addresses of the form 192.168.122.xxx.  I have never seen such an
address on my network.  My virtual machines get addresses of the form
192.168.1.xxx, and those come from the home router.  So I don't think I am
actually using "virbr0".  Wouldn't I need to start some kind of NAT service
before that would be available?