multiple IP addresses on a single machine

I need to create multiple IP addresses for a single machine. The
machine is a linux machine behind a firewall. The machine is assigned
an IP address, but I need to create additional IP addresses for this
machine. Can I assign additional IP addresses for this machine giving
whatever IP addresses I want, or can I only assign additonal IP
addresses as designated by the network admin?

Am Mon, 08 Oct 2007 11:35:53 +0000 schrieb internetgoo:

> I need to create multiple IP addresses for a single machine. The

ifconfig eth0:0 1.1.1.1 netmask 255.255.255.0 up
ifconfig eth0:2 2.2.2.2 netmask 255.255.255.0 up

> machine is a linux machine behind a firewall. The machine is assigned
> an IP address, but I need to create additional IP addresses for this
> machine. Can I assign additional IP addresses for this machine giving
> whatever IP addresses I want, or can I only assign additonal IP
> addresses as designated by the network admin?

You should take only IP adresses which not used in your network, otherwise
you'll get trouble with arp.

cheers

(E-Mail Removed) writes:

>I need to create multiple IP addresses for a single machine. The
>machine is a linux machine behind a firewall. The machine is assigned
>an IP address, but I need to create additional IP addresses for this
>machine. Can I assign additional IP addresses for this machine giving
>whatever IP addresses I want, or can I only assign additonal IP
>addresses as designated by the network admin?


If you told us your problem rather than your solution it would help.
You cannot use public IP addresses unless issued by an authorized person
who can issue such addresses. Addresses are way s for other computers to
connect to yours, and there must be a way to find out on which wires to
send the packets to get those packets to you. That can only be done if
those addresses are "centrally" allocated. And they cannot duplicate.
If you use the private address range 10.x.x.x 192.168.x.x then you can do
with them what you want, since noone will be able to route to them anyway
over the public nets.

However if you want your machine to be found with those addresses, even
private, you had better agree with your network admin.

Now whyin the world do you want to assign multiple addresses to a single
machine?

Burkhard Ott <(E-Mail Removed)> writes:

>Am Mon, 08 Oct 2007 11:35:53 +0000 schrieb internetgoo:

>> I need to create multiple IP addresses for a single machine. The

>ifconfig eth0:0 1.1.1.1 netmask 255.255.255.0 up
>ifconfig eth0:2 2.2.2.2 netmask 255.255.255.0 up

NONONONONONONONONO Do not use public addresses. Use only addresses in the
private ranges. 10.x.x.x or 192.168.x.x


>> machine is a linux machine behind a firewall. The machine is assigned
>> an IP address, but I need to create additional IP addresses for this
>> machine. Can I assign additional IP addresses for this machine giving
>> whatever IP addresses I want, or can I only assign additonal IP
>> addresses as designated by the network admin?

>You should take only IP adresses which not used in your network, otherwise
>you'll get trouble with arp.



>cheers

Hello,

Unruh a écrit :
>
>>ifconfig eth0:0 1.1.1.1 netmask 255.255.255.0 up
>>ifconfig eth0:2 2.2.2.2 netmask 255.255.255.0 up
>
> NONONONONONONONONO Do not use public addresses. Use only addresses in the
> private ranges.

May I ask why ?

> 10.x.x.x or 192.168.x.x

Why does everybody always forget about the third private range,
172.16-31.x.x ? :-D

On 2007-10-08, (E-Mail Removed) <(E-Mail Removed)> wrote:
> I need to create multiple IP addresses for a single machine. The
> machine is a linux machine behind a firewall. The machine is assigned
> an IP address, but I need to create additional IP addresses for this
> machine. Can I assign additional IP addresses for this machine giving
> whatever IP addresses I want, or can I only assign additonal IP
> addresses as designated by the network admin?
>

You can assign any IP address to a machine you control; but if the
packets cannot be routed on the network to some of those IPs, they
will not work properly.

The command is something like

ifconfig eth0:1 ano.th.er.ip
ifconfig eth0:2 yet.mo.re.ip

etc

i

On Mon, 08 Oct 2007, in the Usenet newsgroup comp.os.linux.networking, in
article <(E-Mail Removed). com>,
(E-Mail Removed) wrote:

NOTE: Posting from groups.google.com (or some web-forums) dramatically
reduces the chance of your post being seen. Find a real news server.

>I need to create multiple IP addresses for a single machine.

IP-Alias, Setting Up IP Aliasing On A Linux Machine Mini-HOWTO
Updated: Jan 2001. How to set up and run IP aliasing on a Linux box.

-rw-rw-r-- 1 gferg ldp 13575 Jan 26 2001 IP-Alias

>The machine is a linux machine behind a firewall. The machine is
>assigned an IP address, but I need to create additional IP addresses
>for this machine. Can I assign additional IP addresses for this
>machine giving whatever IP addresses I want, or can I only assign
>additonal IP addresses as designated by the network admin?

If there is an network administrator, I'd _STRONGLY_ advise that
you get addresses from the network administrator, rather than just
randomly grabbing addresses not explicitly authorized by the
admin. At the very least, this can cause confusion and maybe anger,
and could lead to severe disciplinary actions.

Old guy

Pascal Hambourg <boite-a-(E-Mail Removed)> writes:

>Hello,

>Unruh a écrit :
>>
>>>ifconfig eth0:0 1.1.1.1 netmask 255.255.255.0 up
>>>ifconfig eth0:2 2.2.2.2 netmask 255.255.255.0 up
>>
>> NONONONONONONONONO Do not use public addresses. Use only addresses in the
>> private ranges.

>May I ask why ?

If you know enough to ask about the 172range you can answer this yourself.


>> 10.x.x.x or 192.168.x.x

>Why does everybody always forget about the third private range,
>172.16-31.x.x ? :-D

Because it is even more restricted and who cares if they forget about it?

There is nothing wrong with multiple public IP addresses. I have a
server with several IPs. Actually, two such servers.

i