I've asked this on the Xen users list, but had no response so far: I'm running CentOS 5.1 with all current updates: xen-libs-3.0.3-41.el5 xen-3.0.3-41.el5 kernel-xen-devel-2.6.18-53.1.4.el5 kernel-xen-2.6.18-53.1.4.el5 and have a domU config file from another (5.0) server which works. The difference is that on the new machine I want to use routed rather than bridged networking. In bridging mode the domU works fine, but I can't use bridging on this particular server because of the external network configuration. I have modified /etc/xen/config.sxp, commenting out (network-script network-bridge) (vif-script vif-bridge) and uncommenting (network-script network-route) (vif-script vif-route) I've also changed the vif line in the domU config file to: vif = [ 'ip=aaa.bbb.ccc.ddd, vifname=veth1' ] The domU now boots, but has no eth0 interface (the driver doesn't load in the domU because it can't find a suitable device). Is there anything obvious I might have done wrong or missed out? There are no ethernet-related or network device errors in the logs that I can see. James