# lvcreate testvg -L50G -n test-lvm
# mkfs.ext3 /dev/testvg/test-lvm

# virt-install -n testvm -r 2048 --nographics \
--file=/dev/testvg/test-lvm --vcpus=2 --check-cpu \
-l http://192.168.1.2/mirror/centos/5.7/os/x86_64 \
--network=bridge:xenbr0 --network=bridge:xenbr1

HV上で作業
http://d.hatena.ne.jp/clmind/20090329/1238298875

# vi /etc/xen/xend-config.sxp
#(network-script network-bridge)
(network-script network-bridge2)

# vi /etc/xen/scripts/network-bridge2

#!/bin/sh
dir=$(dirname $0)
 
${dir}/network-bridge "$@" vifnum=0 bridge=xenbr0 netdev=bond0 antispoof=yes
${dir}/network-bridge "$@" vifnum=1 bridge=xenbr1 netdev=bond1 antispoof=yes

echo 0 >/proc/sys/net/ipv4/ip_forward

# chmod 755 /etc/xen/scripts/network-bridge2

/etc/init.d/xend restart

ifconfig でxenbr1が追加された事を確認