Subject: dom0/domU bridging - don't get it to work
To: None <port-xen@netbsd.org>
From: Florian Heigl <floh@deranfangvomen.de>
List: port-xen
Date: 09/12/2005 01:30:53
Hi,

I don't want to waste anyone's time, but I just don't get this to work.

I'm running xen-2.0.7 on what I think is the most current snapshot of
3_BETA (NetBSD 3.0_BETA (XEN0) #0: Sat Aug 13 13:50:25), and my dom0
luckily is running fine, with X and everything I could wish for.

I'm trying to run another NetBSD in the first domU; after problems
using a file backend I've simply plugged in an USB stick. It's too=20
small for any real work of course, but OK for testing.=20
Unfortunately, I don't get to ftp the distribution packages.

I need to be able to DHCP the ip address for the domU and somehow just
don't get the bridge to work, and hope someone is able to spot where
I went wrong.

Bridge configuration:

xen-host-2# cat /etc/ifconfig.bridge0                                      =
   =20
create
!brconfig  add fxp0 up

xen-host-2# brconfig -a =20
bridge0: flags=3D41<UP,RUNNING>
[...]
Interfaces:
fxp0 flags=3D3<LEARNING,DISCOVER>
port 1 priority 128
[...]


Domain Config

xen-host-2# cat xm.dom1.netbsd                                             =
  =20
kernel =3D "/export/xen/dom1/netbsd-INSTALL_XENU.gz"
memory =3D 64
name =3D "xen-u-1"
nics =3D 1=20
root =3D "/dev/wd0d"
vif =3D [ 'mac=3Daa:00:00:55:03:f0','bridge=3Dbridge0' ]

in ifconfig I see fxp0, bridge0, and the vif for the domU,=20
the later is not in state 'UP', but manually changing this state
made no difference as far as I can tell.

running tcpdump on fxp0 and vif2.0 I looked for bootps and bootpd
packets and saw none (I hope bootps/d is the right thing for DHCP after
all), honestly I think my bridge simply isn't bridging at all.

I noticed some errors coming from the vif-bridge script ( a [[: error,
as far as I remember) and gave http://lysergic.soclab.eu.org/vif-bridge
by Piotr Stolc a try. The errors are gone now, but otherwise things
are unchanged.=20

I'm not in a hurry with this, but I'd be glad if someone could post back
on it, or if Manuel could add a few bridging notes to the howto.
At the moment I'm really stomped I find it harder to setup xen with a=20
NetBSD dom0. (I'm more kind of a linux-avoiding person, and my distro
had no support for xen, but it worked out far easier.)

I'll be back when I've got a second hard disk for the domU storage
and some sleep for the *cough* hypervisor.

florian

--

florian heigl			 http://deranfangvomen.de/

Grid Computing erfreut sich gerade bei Windows-Nutzern sehr regem Zuspruch,=
 auch
wenn die Rechnerbesitzer meist nichts von ihrem Gl=FCck wissen. --f. weimer