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
			

ifconfig eth0 192.168.0.10 netmask 255.255.255.0
or
ip addr add 192.168.0.10 dev eth0
		

ifcfg-eth0,ifcfg-eth1,ifcfg-eth2 ... ifcfg-eth(n)

		
[root@development httpd]# cat /etc/sysconfig/network-scripts/ifcfg-eth0
# Broadcom Corporation NetLink BCM5784M Gigabit Ethernet PCIe
DEVICE=eth0
BOOTPROTO=static
BROADCAST=192.168.3.255
HWADDR=00:25:64:A3:59:BF
IPADDR=192.168.3.40
IPV6INIT=yes
IPV6_AUTOCONF=yes
NETMASK=255.255.255.0
NETWORK=192.168.3.0
ONBOOT=yes
		
			

eth0:1

		
[root@development httpd]# cp /etc/sysconfig/network-scripts/ifcfg-eth0 /etc/sysconfig/network-scripts/ifcfg-eth0:1
[root@development httpd]# vi /etc/sysconfig/network-scripts/ifcfg-eth0:1
# Broadcom Corporation NetLink BCM5784M Gigabit Ethernet PCIe
DEVICE=eth0:1
BOOTPROTO=static
BROADCAST=192.168.3.255
HWADDR=00:25:64:A3:59:BF
IPADDR=192.168.3.41
IPV6INIT=yes
IPV6_AUTOCONF=yes
NETMASK=255.255.255.0
NETWORK=192.168.3.0
ONBOOT=yes
		
			

reload network

		
[root@development ~]# /etc/init.d/network reload
Shutting down interface eth0:                              [  OK  ]
Shutting down loopback interface:                          [  OK  ]
Bringing up loopback interface:                            [  OK  ]
Bringing up interface eth0:
		
			

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