IP aliasing is the process of adding more than one IP address to a network interface. Typical uses of IP aliasing are virtual hosting of Web and FTP servers. It is fairly simple to set up an IP alias. You merely have to configure the network interface on the system to listen for the additional IP address.

Below are the steps for configuring IP alias under Ubuntu Linux:

If you want to put IP alias on an interface, first find the interface, use command

ifconfig

Open the file - /etc/network/interfaces and add the following entries (here we are adding 2 IP aliases)


auto eth0:1
iface eth0:1 inet static
address 192.168.1.10
netmask 255.255.255.0
broadcast 192.168.1.255
network 192.168.1.0
gateway 192.168.1.1


auto eth0:2
iface eth0:2 inet static
address 192.168.1.11
netmask 255.255.255.0
broadcast 192.168.1.255
network 192.168.1.0
gateway 192.168.1.1
You need to enter all the details like address,netmask,network,broadcast and gateways values after entering all the values save this file and exit.
Next, go to Applications > Accessories > Terminal and run the command below to restart the networking service:

sudo /etc/init.d/networking restart

Then type command ifconfig to see the result.
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