sudo /etc/init.d/networking restart
		

$ sudo ifquery --list
lo
eth0
eth1
			

DHCP

sudo vi /etc/network/interfaces

# The primary network interface - use DHCP to find our address
auto eth0
iface eth0 inet dhcp
			

Static IP

# The primary network interface
auto eth0
iface eth0 inet static
address 192.168.3.90
gateway 192.168.3.1
netmask 255.255.255.0
network 192.168.3.0
broadcast 192.168.3.255

dns-nameservers 8.8.8.8 4.4.4.4
			

Setting up Second IP address or Virtual IP address in Ubuntu

sudo vi /etc/network/interfaces

auto eth0:1
iface eth0:1 inet static
address 192.168.1.60
netmask 255.255.255.0
network x.x.x.x
broadcast x.x.x.x
gateway x.x.x.x

dns-nameservers 8.8.8.8 4.4.4.4