interfaces (Source)

# 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
# dhcp6c handles IPv6 configuration for this interface.
auto eth0
iface eth0 inet static
        address 192.168.0.1
        netmask 255.255.255.0
        network 192.168.0.0
        broadcast 192.168.0.255

# dhcp6c probably also handles all the IPv6 configuration for this interface,
# but this doesn't hurt.
auto eth1
iface eth1 inet dhcp
iface eth1 inet6 auto