/etc/sysctl.conf
> > net.bridge.bridge-nf-call-iptables = 1 >
> net.bridge.bridge-nf-call-ip6tables = 0 >
> net.bridge.bridge-nf-call-arptables = 1
xe-switch-network-backend bridge
REBOOT
原文：http://www.blogjava.net/ivanwan/archive/2014/12/17/421501.html