/etc/network/interfaces (sample)

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
allow-hotplug eth0
iface eth0 inet static
address 119.111.71.98
netmask 255.255.255.240
gateway 119.111.71.97

allow-hotplug eth1
iface eth1 inet static
address 192.168.100.45
netmask 255.255.254.0