I somehow managed to screw up my KVM/QEMU virtual environment and can now no longer connect to the internet. I'm still getting a "virtual gateway" addy at 192.168.222.1 through DHCP, so part of it appears to be working. Traffic just isn't getting routed/NATed/redirected from the virtual gateway to the real NIC anymore (which would then, in turn, send it on to the real gateway at 192.168.1.1 -- simple, huh? LOL).

Anyway, am hoping someone can clue me into exactly how QEMU handles virtualizing the NICs and LAN. The QEMU docs were old (refers to a class A 10.0.2.x addy) and KVM's docs are almost non-existent.

http://fabrice.bellard.free.fr/qemu/qemu-doc.html#SEC26
http://www.qumranet.com/

If it helps I *think* what screwed everything up was Firestarter's wizard. Part of it tries to imitate Microsoft's ICS (Internet Connection Sharing) and I *guess* the NATing setup was overwritten. Thing is QEMU's VLAN appears to be controlled separately, as I could start/stop all my firewall services (iptables, ip6tables and firestarter) without affecting it (before the crash.) So I'm still stumped....

Anywho, luckily I installed both Windows Server 2003 R2 and Windows Server 2003 Web Edition on their own (real) partitions. So I suppose, if I have to, I can just blow away the Linux partition and reinstall without affecting my Windows VMs.

BTW, for some reason Windows Server 2003 Web Edition crashes using KVM. Using just QEMU (no kernel acceleration) works fine though, other than it being really slow, that is.

My latest best guess is a conflict between firestarter and dnsmasq packages. I tried reinstalling making sure to load firestarter before qemu and virt-manager but the VLAN still got hosed. So am now reinstalling for the third time.

I guess firestarter's gotta go. Was one of my favorites.

Back up and running, the hard way: http://4crito.com/screenshots/qemu.png

Grr, I'm about to blow it all away and go native Windows... for the next sucker to come along and waste a weekend:

I can ping everything from inside the VLAN, but the 192.168.222 subnet itself is completely unreachable. So despite the virbr0 name it's clearly acting like a gateway router, not a bridge. In other words, the default setup isn't suitable for hosting a web server and there isn't enough documentation for me to figure out how to do something as simple as forward port 80. In fact, I'd have to say at this stage KVM/QEMU isn't suitable for running any server OS, only client OSes.

Oh, BTW, I found a solution to my KVM problem in the Ubuntu docs.
https://help.ubuntu.com/community/KVM

It's the last section titled "Virtual NICs Bridged Directly to Outside".