Soren, Thanks for your response and well spotted with the network mask, must have got tired staying up playing with this so late!! I have updated the network address on the host the /etc/network/interfaces file now reads ## START /etc/network/interfaces file on HOST ## auto eth0 iface eth0 inet manual auto br0 iface br0 inet static address 88.208.249.44 network 88.208.248.0 netmask 255.255.252.0 gateway 88.208.248.1 bridge_ports eth0 bridge_stp off bridge_fd 0 bridge_maxwait 0 ## END /etc/network/interfaces file on HOST ## These changes have been enabled and I can still ssh between both the host and the guest, but still no external conectivity for the guest. The routing table on the guest is as follows ## START routing table ## Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 88.208.248.0 0.0.0.0 255.255.252.0 U 0 0 0 eth0 0.0.0.0 88.208.248.1 0.0.0.0 UG 100 0 0 eth0 ## END routing table ## Any more ideas? Kind Regards, Jamie. <div class="gmail_quote">On Tue, Jun 8, 2010 at 11:31 PM, Soren Hansen <<a href="mailto:soren@ubuntu.com">soren@ubuntu.com</a>> wrote: <blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;"><div class="im">On Tue, Jun 08, 2010 at 10:49:04PM +0100, Jamie McDonald wrote: > #### START /etc/network/interfaces on HOST #### > > auto eth0 > iface eth0 inet manual > > auto br0 > iface br0 inet static > address 88.208.249.44 > network 88.208.249.0 > netmask 255.255.252.0 > gateway 88.208.248.1 </div>I probably doesn't matter, but that address with that netmask doesn't give that network. <div class="im"> > auto eth0 > iface eth0 inet static > address 88.208.249.45 > netmask 255.255.252.0 > network 88.208.248.0 > broadcast 88.208.251.255 > gateway 88.208.248.1 </div>This adds up, though :) <div class="im"> > Symptoms > ---------------- > I can now ssh from the host into the guest (from the host) and from the > guest to the host, however try as I might I cannot get the guest to access > the outside world or the host to pass packets to the guest. </div>It is not the job of the host to do any of this, really. <div class="im"> > As you can see, the bridge is working and when I start the VM from > virsh# the vnet0 adapter is created, however no tap0 is being created. </div>vnet0 is the tap device. This is the expected behaviour. <div class="im"> > As far as I am aware you should not need ipv4 forwarding enabled in > the Kernel for bridged networks </div>That's correct. <div class="im"> > If any of you could shed any light on this issue (since I can't seem > to find anyone else with the issue) it would be most appreciated. </div>Off the top of my (arguably quite tired) head, it looks good. Can I see the routing table in the guest? -- Soren Hansen Ubuntu Developer <a href="http://www.ubuntu.com/" target="_blank">http://www.ubuntu.com/</a> -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iEYEARECAAYFAkwOxKQACgkQonjfXui9pOMD8gCgq/662euFJg8kaSDnpKvHYU5T EcoAn1FaO6+SO0RSai276jVq84ab/IQr =Cayb -----END PGP SIGNATURE----- </blockquote></div>