I'm trying to set up a private network for the guests using NAT. My intention is to shield them from any direct interaction with the outside world. The host I am working on has only one physical NIC with a public IP assigned to it. For some reason I haven't managed to sort, the guest interface is not getting an ip from the default DHCP provided by libvirt (ideally I would actually use static IP addresses anyway). The interface block in the guest's config file currently looks as follows: Code: <interface type='network'> <mac address='00:16:3e:1a:b3:4a'/> <source network='default'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> </interface> ifconfig returns: /etc/network/interfaces is configured as shown: Code: auto lo iface lo inet loopback auto eth2 iface eth2 inet static address 178.33.xxx.xxx netmask 255.255.255.0 network 178.33.xxx.xxx broadcast 178.33.xxx.xxx gateway 178.33.xxx.xxx Lastly, ifup doesn't seem to find vnet0, although ifconfig lists it. Thanks! [EDIT] Although the vnetX interfaces still display empty, I manage to access the VMs if a static IP is supplied to vmbuilder. As such: Code: vmbuilder kvm ubuntu --suite=precise --flavour=virtual --arch=amd64 --mirror=http://de.archive.ubuntu.com/ubuntu -o --libvirt=qemu:///system --ip=192.168.122.2 --gw=192.168.122.1 --part=vmbuilder.partition --templates=mytemplates --user=administrator --name=Administrator --pass=howtoforge --addpkg=unattended-upgrades --addpkg=acpid --firstboot=/var/lib/libvirt/images/vm2/boot.sh --mem=4096 --hostname=vm2