Make some virtual mac address

Question

I want to make some virtual MAC addresses for my network adapter or wireless adapter, so I can connect to network with more than one IP address from one computer or laptop.

How can I do it? (I know it's possible ,because one of my friends done it in university and have more than one - sometimes up to 255 - IP addresses on a network).

Answer 1

You do not need more that one mac address to have multiple ip addresses on a single network interface. This technique is called ip aliasing.

Each operative system has a slightly different syntax but usually, to set different ip addresses on the same interface, you need only to do something like:

ifconfig eth0 192.168.100.200 netmask 255.255.255.0
ifconfig eth0:1 192.168.120.200 netmask 255.255.255.0
ifconfig eth0:2 192.168.130.200 netmask 255.255.255.0

The example above works on linux. On BSD, you need something like:

ifconfig lnc0 192.168.100.200 netmask 255.255.255.0
ifconfig lnc0 192.168.120.200 netmask 255.255.255.0 alias
ifconfig lnc0 192.168.130.200 netmask 255.255.255.0 alias

Answer 2

Edit: Add hint for setting up virtual device:

First set up an additional device e.g.:

ifconfig eth0:1 up

The you might additionally add an IP to it. e.g.:

ifconfig eth0:1 10.0.0.20 broadcast 10.255.255.255 netmask 255.255.255.255

If you really want to, you can also alter the MAC-address:

$DEVICE="eth0:1"
$MAC="02:73:53:00:ca:fe"
ip link set $DEVICE address $MAC

Note that the second bit of the first byte has to be set to signal a locally administered address (LAA) - which says that this MAC-address is only locally valid (e.g. within your enterprise network) and might not be unique world wide (so you can assign your own MAC-addresses without the need to register them officially).