this is obsolete doc -- see http://doc.nethence.com/ instead

XEN -- Hybrid network configuration 

Introduction 

Let's say we need both, routing AND bridging. 

Dom0 

Create a custom wrapper, 

cd /etc/xen/scripts/

vi network-custom

like, 

#!/bin/ksh

fdummy0_start() {

        print enabling dummy0...

        modprobe dummy

        ifconfig dummy0 up

        brctl addbr dummybr0

        brctl addif dummybr0 dummy0

}

fdummy0_stop() {

        print disabling dummy0...

        brctl delif dummybr0 dummy0

        brctl delbr dummybr0

        ifconfig dummy0 down

        rmmod dummy

}

[[ $1 = start ]] && fdummy0_start

[[ $1 = stop ]] && fdummy0_stop

${0%/*}/network-route $@ netdev=eth0

enable it, 

chmod +x network-custom

DomU 

Specify which vif-script to use into guest's configuration, for example, 

vif = [ 'vifname=vbsd64.0,script=vif-route,ip=XX.XX.XX.XX',\

        'vifname=vbsd64.1,script=vif-bridge,bridge=dummybr0' ]