Xen 3.1 virtual network
I am running Kubuntu (Gutsy) on my laptop and decided to install a Debian xen guest, following the HOWTO for the perfect xen/etch setup. Since dom0 is a laptop and I connect through ubuntu network manager with the internet a virtual network setup for xen seemed to be appropriate.
Following the HOWTO page for the virtual network worked nearly perfect (danke Falko!). However, I was not able to ping outside the virtual network. The solution for me was enabling NAT forwarding on Dom0 as described in an older HOWTO (perfect xen setup for ubuntu/debian), replacing of course the ip.
Reading the xen 3.1 HOWTO, I had the impression that nat forwarding is not needed for xen 3.1.