http://www.progtutor.com/blog/7-tips-tuts/751-static-ip-configuration-in-ubuntu-1204-lts
Static IP configuration in Ubuntu 12.04 LTS
Friday, 27 April 2012 11:05 David Tran
There are tons of changes in Ubuntu 12.04 LTS and The most notable difference for the user is that any change manually done to /etc/resolv.conf will be lost as it gets overwritten each time something triggers resolvconf. Instead,Networking38resolvconf uses DHCP client hooks, and /etc/network/interfaces to generate a list of nameservers and domains to put in /etc/resolv.conf, which is now a symlink: /etc/resolv.conf -> ../run/resolvconf/resolv.conf
To configure the resolver, add the IP addresses of the nameservers that are appropriate for your
network in the file /etc/network/interfaces. You can also add an optional DNS suffix search-lists
to match your network domain names. For each other valid resolv.conf configuration option, you can
include, in the stanza, one line beginning with that option name with a dns- prefix. The resulting file
might look like the following:
# The primary network interface
auto eth0
iface eth0 inet static
address 192.168.9.100
netmask 255.255.255.0
network 192.168.9.0
broadcast 192.168.9.255
gateway 192.168.9.254
dns-search example.com
dns-nameservers 8.8.8.8
