After basic installation of Jaunty, I need to setup my network interface card, so I can update my new OS with its repository site. First, I have to configure my NIC with IP Address and setting up DNS. Start with editing file /etc/network/interfaces with following command :
sudo vi /etc/network/interfaces
and enter the following lines according to my NIC :
# The primary network interface
auto eth0
iface eth0 inet static
address 192.168.1.9
gateway 192.168.1.1
netmask 255.255.255.0
network 192.168.1.0
broadcast 192.168.1.255
After entering all the details above, I must restart the network services using the following command :
sudo /etc/init.d/networking restart
After setting for IP Address, I must setting DNS. We can add hostname and IP addresses to the file /etc/hosts for static lookups. To cause my machine to consult with a particular server for name lookups I simply add their addresses to /etc/resolv.conf. For example a machine which should perform lookups from the DNS server at IP address 192.168.1.2 would have a resolv.conf file looking like this
sudo vi /etc/resolv.conf
enter the following details
search test.com
nameserver 192.168.1.
After done, I can start update my Jaunty from repo. First choose System -> Administration -> Software Sources find and click download from …. choose Other… and click Select Best Server, done and Close.

Software Sources

Select Best Server
From terminal use following command :
sudo apt-get update

sudo apt-get update
After done, use command :
sudo apt-get upgrade
to upgrade my Jaunty.