auto lo
iface lo inet loopback

# The primary network interface
auto eth0
iface eth0 inet static
address 10.1.1.21
netmask 255.255.255.0
gateway 10.1.1.1
dns-nameservers 8.8.8.8

auto eth0:0
iface eth0:0 inet static
     address 10.1.1.22
     netmask 255.255.255.0

auto eth0:1
iface eth0:1 inet static
     address 10.1.1.23
     netmask 255.255.255.0

auto eth0:2
iface eth0:2 inet static
     address 10.1.1.24
     netmask 255.255.255.0