There is a simple set of commands to get you started
/sbin/ifconfig eth0 up
will bring the network interface eth0 up, if it isn't first NIC use eth1 and so on
You can add default gateway with
Code:
route add xxx.xxx.xxx.x eth0 && route add default gw xxx.xxx.xxx.x
where xxx.xxx.xxx.x is gateway
And verify the routing table with
netstat -rn