# ifconfig

display active interface status

# ifconfig eth0 up

enable interface eth0

# ifconfig eth0 down

disable interface eth0

# ifconfig eth0 192.168.0.10

set the IP address of interface eth0 to 192.168.0.10

# ifconfig eth0 netmask 255.255.255.248

set the subnet mask for interface eth0 to 255.255.255.248