MAC address

[Bangieff]

Hi all
I have a short question: how may I change my LAN card's IP address (under Linux OS)

 

[gunthnp]

which verion on linux if you have webadmin that by far is the easiest way. So long and thanks for all the fish.

 

[Bangieff]

I'm using Linux Slackware 7
I already found the answer of my previous question but I have a new one now
I have two IP adressess assigned on my ethernet card
How may I change the mac address for eth0:1 so it to be different than the eth0's?
In fact I wonder is it possible???

 

[gunthnp]

if you are talking about the mac adress and not the tcp/ip its not, the mac adress is given by the maker of the card, and you only get one. To do it you need to add a 2nd card. So long and thanks for all the fish.

 

[Bangieff]

You are wrong
I can change my LAN card's MAC (and I did) but my question was if it's possible one card with two IP addresses to have two MAC addresses.
Sorry about the mistake in my first letter - I meaned MAC instead of IP address.

 

[gunthnp]

are you sure you chaged the mac address its a six set of 2 letters or numbers and not the tcp/ip address because MAC address a registered with IEEE for each company so you see you can't change for there is a chance you end up on some on else number. So long and thanks for all the fish.

 

[gunthnp]

oh there is some cards that don't have MAC address but have DLC and they can do with those what they want because no one watchs them like IEEE IETF so you might be able to change a DLC address it depend on the maker of the card So long and thanks for all the fish.

 

[Bangieff]

Afcourse I'm sure...and you're wrong about the MAC addresses. Most of them can be changed - man ifconfig
Let me show you what happened to my 3COM LAN card's address
before:
192.168.0.2 ether 00:20:AF:36:74:AC C eth0
after:
192.168.0.2 ether 00:C0:260:0C:C9 C eth0

that's what "arp -n" returned me

 

[gunthnp]

here is the list of comapnys and the mac adrees they own it not every number its the the one that are to the 802.2 standard it does look like you chaged and i am wrong at lest with that card can you put up how. So long and thanks for all the fish.

 

[gunthnp]

sorry here is the address

http://standards.ieee.org/regauth/oui/oui.txt

So long and thanks for all the fish.

 

[Bangieff]

It's absolutely clear to me there are standarts and the MAC addressess are different for each card and etc... (I'm a student and that's my specialization)
If you give me E-mail or something I can upload you the C source I downloaded and have use.... (In fact the same job may be done using ifconfig (read carefully the manual))

have a nice fishing

 

[talisker]

Yes, you can change the MAC address of most newer NICs, but it's generally a bad idea in a network situation because duplicate MAC addresses can occur. These are extremely difficult to diagnose in large networks.

No, you can't have more than one MAC address per NIC. Multiple IP addresses YES, multiple MAC addresses NO. This is because the MAC address is a hardware address representing a single piece of hardware (NIC). An IP address is a logical network address - one NIC or network interface can belong to more than one network & therefore have more than one IP address.

Having two IP addresses with the same MAC should not cause problems - is there a specific reason why you would be concerned?

 

[gunthnp]

i would like to take a look at it my email is Guthnp@yahoo.com So long and thanks for all the fish.

 

[Bangieff]

Not only the "newer" LAN cards - mine is 3c509....I think this model is at least 3-4 years old...

But thanks for explanation. I thought it may be something like that but couldn't find any documentation...

 

[juggy]

Ive been working in token ring for many years and we have been changing mac addresses for ages. Well its not stictly true the MAC address is a burnt in address that does not change and is suppposed to be unique to every card. In token ring and ethernet you can mask the id with a locally administered address found in advanced tab in windows of the card. This makes the address you set the one you will see in management software. Some ethernet cards support this facility. As far as Ive alway understood the MAC address of a NIC installed in your pc will always be fixed. Software will change it.

 

[Bangieff]

Yes some LAN cards support this feature (their MAC address to be permanently changed) but most of them doesn't. And that's the case I'm talking about. But my main question was answered already (is it possible 1 LAN card to have different MAC addressess for each virtual IP address)
thanx to everyone
Martin

 

[Guest_imported]

Is it possable to install 2 NIC cards on the same PC running Windows 98,

 

[gunthnp]

yes So long and thanks for all the fish.