Two or more different ip addresses on one NIC?

izvrashenj · 03-30-2007, 09:20 AM

So please tell me which is the best way to assign two or more external (internet) ip addresses to one network card? I have a server. And i one to use on it many ip addresses.
I have Debian Linux 2.6.20.1 etch.
In /etc/network/interfaces i have:

auto lo
iface lo inet loopback

allow-hotplug eth0
iface eth0 inet static
address 81.198.23.99
netmask 255.255.255.224
network 81.198.23.0/26
broadcast 81.198.23.192
gateway 81.198.23.97

So, is it ok to make my nic to use also second ip address in this way:

auto lo
iface lo inet loopback

allow-hotplug eth0
iface eth0 inet static
address 81.198.23.99
netmask 255.255.255.224
network 81.198.23.0/26
broadcast 81.198.23.192
gateway 81.198.23.97

allow-hotplug eth0:0
iface eth0:0 inet static
address 81.198.23.100
netmask 255.255.255.224
network 81.198.23.0/26
broadcast 81.198.23.192
gateway 81.198.23.97

??? Please tell me cause my server is about 100 miles from me and i don't want to take it down with wrong settings..

Poetics · 03-30-2007, 02:08 PM

You're definitely on the right track -- I've done this recently for a server with one NIC and 13 usable IP addresses. I did a quick Google search for "virtual interface" and the first results were all useful.

It's not difficult once you get the hang of it.
Enjoy!

izvrashenj · 03-30-2007, 04:50 PM

Quote:

Originally Posted by Poetics

You're definitely on the right track -- I've done this recently for a server with one NIC and 13 usable IP addresses. I did a quick Google search for "virtual interface" and the first results were all useful.

It's not difficult once you get the hang of it.
Enjoy!

Ok thanks i'll try it out

Then eth0:0 is fine as second interface or i should use eth0:1?
and for all other ips eth0:2 eth0:3 eth0:4 etc?

JimBass · 03-30-2007, 04:56 PM

Here is a snippet from /etc/network/interfaces on a machine with multiple addresses on its second, NIC, eth1.

Code:

auto eth0
iface eth0 inet static
        address 205.185.197.100
        netmask 255.255.255.0

auto eth1
iface eth1 inet static
        address 192.168.102.252
        netmask 255.255.255.0
        network 192.168.102.0
        broadcast 192.168.102.255
        gateway 192.168.102.2

auto eth1:1
iface eth1:1 inet static
        address 10.0.0.252
        netmask 255.255.255.0

auto eth1:2
iface eth1:2 inet static
        address 192.168.100.252
        netmask 255.255.255.0

auto eth1:3
iface eth1:3 inet static
        address 192.168.101.252
        netmask 255.255.255.0

Peace,
JimBass