How can ethernet card get multiple IP from DHCP server ?

I've got linux 2.6 router with 2 ethernet cards. eth0 is connected to
internet provider that assigns IP numer from DHCP server, eth1 is
connected to LAN.

provider gives me unlimited number of external IPs, when I'm
connecting devices.

I would like my linux server to get couple external IPs. So Eth0 shoud
have multiple MAC addresses. How can it be done ?

Seems like solvation is described here http://en.wikipedia.org/wiki/Proxy_ARP
(Taking multiple addresses from a LAN), but can anyone give me live
example ?


thanx in advance !

On Wed, 29 Aug 2007 08:37:59 -0000, (E-Mail Removed)
<(E-Mail Removed)> wrote:
>
>
> I've got linux 2.6 router with 2 ethernet cards. eth0 is connected to
> internet provider that assigns IP numer from DHCP server, eth1 is
> connected to LAN.
>
> provider gives me unlimited number of external IPs, when I'm
> connecting devices.
>
How can you have an unlimited number of external IPs? It should be
possible to set aside one or two static IPs from the range that you are
allotted.


--
Power, n.:
The only narcotic regulated by the SEC instead of the FDA.

(E-Mail Removed) wrote:
> Seems like solvation is described here http://en.wikipedia.org/wiki/Proxy_ARP
> (Taking multiple addresses from a LAN), but can anyone give me live
> example ?

I found this:

http://www.sjdjweis.com/linux/proxyarp/

Regards,

Mark.

--
Mark Hobley
393 Quinton Road West
QUINTON
Birmingham
B32 1QE

Email: markhobley at hotpop dot donottypethisbit com

http://markhobley.yi.org/

(E-Mail Removed) said:
>I've got linux 2.6 router with 2 ethernet cards. eth0 is connected to
>internet provider that assigns IP numer from DHCP server, eth1 is
>connected to LAN.
>
>I would like my linux server to get couple external IPs. So Eth0 shoud
>have multiple MAC addresses. How can it be done ?
>
>Seems like solvation is described here http://en.wikipedia.org/wiki/Proxy_ARP
>(Taking multiple addresses from a LAN), but can anyone give me live
>example ?

You don't even need proxy arp; you need DHCP client that:
- can attach to virtual interfaces (eth0:1, ...)
- supports user-assignable DHCP client-id

.... I've written about this a few times earlier; do a google groups
search with my address and dhcp, and you should find something.
--
Wolf a.k.a. Juha Laiho Espoo, Finland
(GC 3.0) GIT d- s+: a C++ ULSH++++$ P++@ L+++ E- W+$@ N++ !K w !O !M V
PS(+) PE Y+ PGP(+) t- 5 !X R !tv b+ !DI D G e+ h---- r+++ y++++
"...cancel my subscription to the resurrection!" (Jim Morrison)

> I found this:
>
> http://www.sjdjweis.com/linux/proxyarp/

But how does it solves my problem ?

I need to create "vrtual interfaces" with their mac addresses visible
in network ?
can you provide some example ?

> >I've got linux 2.6 router with 2 ethernet cards. eth0 is connected to
> >internet provider that assigns IP numer from DHCP server, eth1 is
> >connected to LAN.
>
> >I would like my linux server to get couple external IPs. So Eth0 shoud
> >have multiple MAC addresses. How can it be done ?
>
> >Seems like solvation is described herehttp://en.wikipedia.org/wiki/Proxy_ARP
> >(Taking multiple addresses from a LAN), but can anyone give me live
> >example ?
>
> You don't even need proxy arp; you need DHCP client that:
> - can attach to virtual interfaces (eth0:1, ...)
> - supports user-assignable DHCP client-id
>
> ... I've written about this a few times earlier; do a google groups
> search with my address and dhcp, and you should find something.
> --


Sorry, it does not works.

I guess It can be solved this way: create virutal interfaces (like
vmware does) with different mac addresses, and then route (maybe with
proxy arp) packets to eth or loopback interface... But how ?

(E-Mail Removed) wrote:

> But how does it solves my problem ?

Ok. I misunderstood your problem. I thought you wanted to know about proxy
ARP, which is what the link you posted was about.

> I need to create "vrtual interfaces" with their mac addresses visible
> in network ?

It might be an idea to clarify your setup, and what you are trying to achieve
so that we can provide a solution.

You say that your ISP has given you multiple IP addresses. Do all these
addresses map to the single ethernet port that you have on the internet side?
Do the addresses change, or are they static? Are you using all the addresses
that have been provided? (I know you said DHCP, but you can have static DHCP,
ie, each interface always gets the same IP address.)

You are requesting several IP addresses from the DHCP server. What happens to
these addresses?

Does the incoming cable go straight to the back of the computer, or are there
routers, cable modems, etc involved in the chain?

What incoming traffic are you expecting on each of the provided IP addresses?

How does the traffic that you expect on the first IP address differ from
traffic on the second IP address, etc?

How have you configured the computer that has the two ethernet cards? What
relevant services and packages have you got running?

Regards,

Mark.

--
Mark Hobley
393 Quinton Road West
QUINTON
Birmingham
B32 1QE

Email: markhobley at hotpop dot donottypethisbit com

http://markhobley.yi.org/

> It might be an idea to clarify your setup, and what you are trying to achieve
> so that we can provide a solution.

Ok, here's detailed information:

Take a look at this picture:

http://img517.imageshack.us/my.php?image=ryskn5.gif

Desktop 1, Desktop 2 and eth0 interface of Linux server get external
IP addresses from dhcp server.
If I want to connect next device to this zone I've to connect it to
first swith and reset provider's modem.

I run dhcp server on linux server, so desktop computers attached to
eth1 interface get IP addresses (192.168.1.*)

I want to be able to assign multiple external IP addresses to eth0
interface. So eth0 must have "multiple MAC addresses". I would like to
assingn those new IP addresses to eth0:1, eth0:2, eth0:3 ...
interface.


>
> You say that your ISP has given you multiple IP addresses. Do all these
> addresses map to the single ethernet port that you have on the internet side?

I hope that description above explains this.

> Do the addresses change, or are they static?

They're "almost static". I mean that they haven't changed since couple
months, but provider doesn't guarantee they're static.

> Are you using all the addresses
> that have been provided? (I know you said DHCP, but you can have static DHCP,
> ie, each interface always gets the same IP address.)

They don't limit ip addressess. there must be some limit, but I've
never been able to reach it.

> You are requesting several IP addresses from the DHCP server. What happens to
> these addresses?

I hope you find answer above

> Does the incoming cable go straight to the back of the computer, or are there
> routers, cable modems, etc involved in the chain?

See picture

>
> What incoming traffic are you expecting on each of the provided IP addresses?

I would like to create diferent routes for difrerent services.


> How does the traffic that you expect on the first IP address differ from
> traffic on the second IP address, etc?

I could redirect whole incoming traffic to one of IPs to desktop4
computer

>
> How have you configured the computer that has the two ethernet cards?

Linux 2.6 + iptables + imq + patch-o-matic + iproute2 + dnscache.....