Hello all,

I need to change the MAC address of a NIC inside a FW. The reason ? My
provider has gateway that watch IP AND MAC ... so if I give my IP to
another NIC than the one I had at first, nothing can go.

Of course, I'm using OpenBSD 3.3. And the NIC I need to change the MAC is
a xl device.

THanks in Advance,
JF

--
Jean-Francois Gobin - Administrateur gobinjf.be
http://www.gobinjf.be mailto:gobin@gobinjf.be

> I need to change the MAC address of a NIC inside a FW. The reason ? My
> provider has gateway that watch IP AND MAC ... so if I give my IP to
> another NIC than the one I had at first, nothing can go.
>
> Of course, I'm using OpenBSD 3.3. And the NIC I need to change the MAC is
> a xl device.

Tried contacting your ISP and requested the changes? (to IP/MAC etc etc)
Or are these practices they rather woudn't have going on?

Sacha

> I need to change the MAC address of a NIC inside a FW. The reason ? My
> provider has gateway that watch IP AND MAC ... so if I give my IP to
> another NIC than the one I had at first, nothing can go.

Changing of MAC addresses is not officially supported by OpenBSD. There
is only a hack around that wont really fit your needs. Contact your ISP
or change the OS.

ccm.

Caspar Clemens Mierau <damokles@gmx.net> wrote:
>> I need to change the MAC address of a NIC inside a FW. The reason ? My
>> provider has gateway that watch IP AND MAC ... so if I give my IP to
>> another NIC than the one I had at first, nothing can go.

> Changing of MAC addresses is not officially supported by OpenBSD. There
> is only a hack around that wont really fit your needs. Contact your ISP
> or change the OS.


Come on !

Why not recognize that there IS legitimate reasons to use other
MAC-addresses then those burnt-in ones.

Most "broadband gateways" ( d-link 604 comes to my mid) even
has a meny to change MAC-address to whatever you want.

If you are trying to get rid of an OpenBSD supporter/user you
might have done it right now. Is that what you really want ?


Don't forget that the concept of MACaddresses relies on a shaky ground,
trying to get any more security then obscurity is a mistake.

> ccm.

--
Peter Håkanson
IPSec Sverige ( At Gothenburg Riverside )
Sorry about my e-mail address, but i'm trying to keep spam out,
remove "icke-reklam" if you feel for mailing me. Thanx.

phn@icke-reklam.ipsec.nu wrote:

> Caspar Clemens Mierau <damokles@gmx.net> wrote:
>>> I need to change the MAC address of a NIC inside a FW. The reason ?
>>> My provider has gateway that watch IP AND MAC ... so if I give my IP
>>> to another NIC than the one I had at first, nothing can go.
>
>> Changing of MAC addresses is not officially supported by OpenBSD.
>> There is only a hack around that wont really fit your needs. Contact
>> your ISP or change the OS.
>
>
> Come on !
>
> Why not recognize that there IS legitimate reasons to use other
> MAC-addresses then those burnt-in ones.

There aren't. Realize that it is attempted to give a unique mac address
to each individual ethernet card. You propose to

>
> Most "broadband gateways" ( d-link 604 comes to my mid) even
> has a meny to change MAC-address to whatever you want.

OpenBSD is a little bit more than a broadband gateway.

>
> If you are trying to get rid of an OpenBSD supporter/user you
> might have done it right now. Is that what you really want ?

OP should have gone to his ISP. Is there something wrong with that?

>
>
> Don't forget that the concept of MACaddresses relies on a shaky
> ground, trying to get any more security then obscurity is a mistake.
>

The choice not to support changes in mac addresses might be in different
grounds that what you're hinting at.

Does this discussion have to come up every week again? Please use google
to find the legimiate reasons _not_ to change.

EJ
--
Remove the obvious part (including the dot) for my email address.
http://www.vanwesten.net for examples of ipf and pf.

No, it isn't to obfuscate anything. I'm moving from one firewall to
another (in fact, switching machine), but it came out of my mind that in
the current technology, my ISP has set my IP/MAC association in their
gateway. And that's something they don't like to change (because they
don't know how to do it, have to call a technical guy and so on).

TO summarize, it may take a whole week before they change the IP/MAC
association in the gw. If I can change the MAC of the NIC, I may be able
to switch the machine quite transparentely.

JF


On Sat, 18 Oct 2003 phn@icke-reklam.ipsec.nu wrote:

> Caspar Clemens Mierau <damokles@gmx.net> wrote:
> >> I need to change the MAC address of a NIC inside a FW. The reason ? My
> >> provider has gateway that watch IP AND MAC ... so if I give my IP to
> >> another NIC than the one I had at first, nothing can go.
>
> > Changing of MAC addresses is not officially supported by OpenBSD. There
> > is only a hack around that wont really fit your needs. Contact your ISP
> > or change the OS.
>
>
> Come on !
>
> Why not recognize that there IS legitimate reasons to use other
> MAC-addresses then those burnt-in ones.
>
> Most "broadband gateways" ( d-link 604 comes to my mid) even
> has a meny to change MAC-address to whatever you want.
>
> If you are trying to get rid of an OpenBSD supporter/user you
> might have done it right now. Is that what you really want ?
>
>
> Don't forget that the concept of MACaddresses relies on a shaky ground,
> trying to get any more security then obscurity is a mistake.
>
> > ccm.
>
>

--
Jean-Francois Gobin - Administrateur gobinjf.be
http://www.gobinjf.be mailto:gobin@gobinjf.be

Jean-Francois Gobin wrote:

> No, it isn't to obfuscate anything. I'm moving from one firewall to
> another (in fact, switching machine), but it came out of my mind that
> in the current technology, my ISP has set my IP/MAC association in
> their gateway. And that's something they don't like to change (because
> they don't know how to do it, have to call a technical guy and so on).
>
> TO summarize, it may take a whole week before they change the IP/MAC
> association in the gw. If I can change the MAC of the NIC, I may be
> able to switch the machine quite transparentely.
>

Why don't you use the easiest solution: move the nic from one machine to
another. That doesn't take much time.

EJ
--
Remove the obvious part (including the dot) for my email address.
http://www.vanwesten.net for examples of ipf and pf.

> If you are trying to get rid of an OpenBSD supporter/user you
> might have done it right now. Is that what you really want ?

Haven't tried to. He won't get any better answer. This question has been
asked very often - I've been looking for a long time for a solution for
this. OpenBSD decided not to implement this feature and it's ok. If you
want a stable OpenBSD you have to find another solution. "sea.c", that
can be found here: *hinthint*

http://www.netsys.com/openbsd-tech/1.../msg00020.html

is a pain. So there a four options left:

1.) move the nic

2.) change the os

3.) contact the isp

4.) let it be

I think it's not a pity to say that there features that OpenBSD cannot
provide right now.

ccm.

In article <3f914b9f$0$58700$e4fe514c@news.xs4all.nl>, erik wrote:
> Jean-Francois Gobin wrote:
[snip: change mac address?!?!]
>
> Why don't you use the easiest solution: move the nic from one machine to
> another. That doesn't take much time.

But! But! My HP 9000/D200 doesn't have SBUS slots!


--
j p d (at) d s b (dot) t u d e l f t (dot) n l .

>
> 1.) move the nic
Thought of it. But it's a bit longer than just switch my two fw.

> 2.) change the os
Why ?

> 3.) contact the isp
As I told previously, they are "technological idiots". And proud of it.

> 4.) let it be
"Mother mary speaks the word of wisdom ..." ... Let that to the Beattles,
please.

> I think it's not a pity to say that there features that OpenBSD cannot
> provide right now.
I didn't blame OpenBSD, i just asked if it was possible.


--
Jean-Francois Gobin - Administrateur gobinjf.be
http://www.gobinjf.be mailto:gobin@gobinjf.be