This is the content of my /etc/network/interfaces

# 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 72.20.5.18
	netmask 255.255.255.252
	network 72.20.5.16
	broadcast 72.20.5.19
	gateway 72.20.5.17
	# dns-* options are implemented by the resolvconf package, if installed
	dns-nameservers 72.20.1.2
	dns-search staminus.net



I want to add additional ips. These are the infos of the ips:

Primary IP Subnet: 72.20.5.16/30
Primary Usable IP Address: 72.20.5.18
- Gateway: 72.20.5.17
- Netmask: 255.255.255.252
- Broadcast: 72.20.5.19

IRC IP Subnet: 72.20.35.0/26
Usable IRC IP Range: 72.20.35.1 through 72.20.35.62
- Netmask: 255.255.255.192
- Broadcast: 72.20.35.63


How should i add then in the /etc/network/preferences so as i can start using them on my server please?

Thanks