apt-get install xen-linux-system xen-tools
dpkg-divert --divert /etc/grub.d/08_linux_xen --rename /etc/grub.d/20_linux_xen
update-grub
==== /etc/xen/xend-config.sxp ====
vim /etc/xen/xend-config.sxp
change the following lines to use bridging network setting