Qemu networking issue

[Trent Nelson]

[ Please CC me on replies as I'm not subscribed to this list. ]

I've got a 6.2-STABLE box that I'm running qemu 0.9.0 on, hosting a
Windows 2003 guest OS.  I've got an em0 interface configured with the IP
address 216.203.62.30 (default route: 216.203.62.29), as well as ten
aliased (public) IPs, one of which happens to be 205.97.38.47, which I
want to dedicate to this particular virtual machine, as if it were a
jail.

How do I get the Windows guest to use the 205.97.38.47 IP address?
After a day of googling and trying half a dozen different approaches,
nothing I try seems to work.

I've tried the sysctl net.link.ether.bridge and ifconfig bridge0
approaches mentioned in [1-4].  This initially involved having a tap0
inet 0.0.0.0 broadcast 0.255.255.255 interface, and a bridge0 with
em0,tap0 (and no assigned IP for the bridge), but when I tried to tell
the Windows box to use IP 205.97.38.47 (after I've removed this aliased
IP from em0), subnet 0xffffff00, gateway 216.203.62.29, the local
connection properties dialog would hang with 'Acquiring address...' then
eventually fail.  If I picked an IP address like 192.168.0.1, it would
go through, but there wouldn't actually be any network connectivity
between the host/guest.

When 205.97.38.47 was aliased to em0, Windows would complain that there
was another IP on the network with the same IP (which is to be expected
I guess), and dmesg would have a bunch of arp messages about the qemu
guest mac address '52:54:00:12:34:56' trying to use em0's 205.97.38.47,
also to be expected.  I tried a few things like using the qemu mac
address for tap0, setting tap0's inet to 205.97.38.47 instead of
0.0.0.0, keeping 0.0.0.0 but having 205.97.38.47 as an alias, setting
bridge0's inet to 205.97.38.47 and playing with the arp table to coerce
things further, but nothing resulted in traffic between the host/guest.

Anyone have any insight?

	Trent.

 [1]: http://www.nabble.com/Virtual-network-with-qemu-t3940434.html
 [2]:
http://docs.freebsd.org/cgi/getmsg.cgi?fetch=111250+0+archive/2007/freeb
sd-emulation/20070603.freebsd-emulation
 [3]: http://forums.bsdnexus.com/viewtopic.php?id=1563
 [4]: http://acidos.bandwidth-junkies.net/index.php?Sect=qemu