OpenBSD Journal

ifconfig(8) can now change lladdr

Contributed by phessler on from the do-it-right dept.

ifconfig(8) now supports changing lladdr, which is more commonly known as your MAC address.

(Comments are closed)

  1. By Anonymous Coward ( on

    Contributed by phessler on Thu Apr 13 05:52:00 2006 (GMT) delayed

    Wow, an article from the future. Does this mean the mentioned feature will first be available in a year?

    1. By Anonymous Coward ( on

      No, they went forward in time to grab the code and bring it back to the past. The assumption is that the code was already written in the past so that they could go into the future and implement it. Wonder what happens when we finally catch up to the future? Is it past, present or still future code? Wonder if OpenBSD is the core OS of the Time machine used? Possibly in the future sometime or is that past?

      1. By Amir Mesry ( on

        Sadly I used to believen Time travel was possible. What was really sad was how I found it why it won't ever be possible in my lifetime and a few more after that. Not having enough computing power really sucks.

        1. By Anonymous Coward ( on

          Dude, time travel is possible!!! All you need is that dang flux capacitor and a DeLorean. The sad part is that DeLoreans aren't easy to come by.

          1. By CODOR ( on

            Phone booths aren't too hard to find, although they can get pretty cramped with more than three people or so in them. I hear police call boxes are much roomier inside, but they weren't too common on this continent...

          2. By Anonymous Coward ( on

            You do realize that would require at least 1.21 gigawatt's right? Crazy bastard.

            1. By ViPER ( on

              I'm thinking bikes, dynamo's & Beowulf here.
              Now where do we find 1mil idi..people willing to sweat like a mofo :)

              1. By Gimlet ( on

                I'm thinking bikes, dynamo's & Beowulf here.
                Now where do we find 1mil idi..people willing to sweat like a mofo :)

                You could probably get some kids from a rave and have them do Dance Dance Revolution until whatever they're on wears off. The worst part is the 36 hours of boom-sh-boom-sh-boom-sh.

        2. By Punk Walrus ( on

          I time travel all the time. I did while I typed this sentence. The problem is, I can't travel backwards, and I can't seem to control the rate I travel forward without alcohol.

      2. By kokamomi ( on

        wow! what's the secret cvs checkout tag for this?

      3. By Anonymous Coward ( on

        I'm sure *make* will love this

  2. By Anonymous Coward ( on

    Why this change? This has come up a zillion times before..

    1. By James Herbert ( on

      If it's come up a zillion times, then why are you asking?

      Finally someone rendered this code into something that was commitable, and hence it was committed!

      1. By Arse ( on


  3. By johannes ( on

    Cool, thank you very much. Now I won't have to download and compile sea.c every time :) Thanks!

  4. By Anonymous Coward ( on

    Will this work on all NIC's, or is it that some NIC's you can't change the MAC address at all? Just curious.

    I once changed the MAC address on an fxp card using the Intel tools on the driver floppy because my ISP (AT&T Cable at the time) used the MAC address to authenticate me on the network. I realized this when I got a new computer and I couldn't get on the Internet, so what I did is swapped the MAC addresses on the old computer's NIC and the new computers NIC. That got me up and running.

    Other than instances like that, what other reasons would there be to change the MAC address?

    1. By tedu ( on

      it may not work because the driver decides to ignore it, or because the hardware is funny.

      1. By SubAtomic Toad ( on

        Where can I get this funny hardware? When things aren't working properly I could always use a joke. I don't think any of my hardware has ever been funny. That's probably why my case has so many dents in the side of it. :)

        1. By Lennart Fridén ( on

          Funny peculiar, not funny haha.

    2. By RC ( on

      > I once changed the MAC address on an fxp card using the Intel
      > tools on the driver floppy because my ISP (AT&T Cable at the
      > time) used the MAC address to authenticate me on the network.

      Actually, you were most likely mistaken... Cable modems store your MAC address in RAM, and won't work with anything else until they are cold-rebooted.

      People very often forget this step (or don't realize they need to do it) and change their new card's MAC address, when all they need to do is unplug the modem for a second.

      1. By lolster ( on

        At least with chello/UPC in Austria I am quite sure they use it for authentication. I once didn't change the MAC when I plugged in a new NIC and instead called the provider so they change the one they expect.

      2. By Anonymous Coward ( on

        true, though in my experience, it's more like 30 sec to 1 min for the modem to lose the MAC, 1 sec does not suffice on mine.

        It also involved running from one room to the other to plug/unplug the cables so the router would get the dhcp'd IP before the modem came up fully and hogged it. Bit dodgy. I could have another subnet and double nat, but I see no point.

        evidently, now that we have time travel ...

      3. By Anonymous Coward ( on

        Nope, I'm not mistaken. I'm not saying that your wrong either. Now-a-days, you're method would hold true. But nearly 7 years ago, AT&T most definately did use the MAC address for authentication.

        I know this, because I had to call in my MAC address when I setup the Cable service. Just at the time when I swapped computers, I had forgotten that I did that. I evenually remembered that step and that's when I swapped the MAC addresses.

        Which is funny, now thinking about it, it would have probably been easier to just swap the cards themselves. Doh! Hind sight is 20/20. There must have been a reason why I didn't do that. It's getting way too hard to remember what I did nearly 6 or 7 years ago.

        1. By almeida ( on

          He's right. With AT&T (and before them, Road Runner), you had to phone in the MAC address. They'd come and install the cable, modem, and setup one computer. After the technician left, you quickly pulled your router out of its hiding spot, called them up, and told them you were "switching NICs." Then, you wait for the change, setup NAT, and get the rest of the house connected. It was a pain.

  5. By Oliver ( on

    Really great news, thanks to all who made this possible! For "interesting" MAC-Adressess see Ethernet Codes and have lot's of fun ;-)

    1. By Anonymous Coward ( on

      00404F	Space & Naval Warfare Systems
      00005E	U.S. Department of Defense (IANA)
      00007D	Cray Research Superservers,Inc
      00C0ED	US Army Electronic Proving Ground
      sound a lot cooler than

      002018	Realtek
      Hacking someone local with 00404F0DEAD0DEAD could be fun to mess with their head. ; )

      1. By Anonymous Coward ( on

        Personally, I prefer:

        0000D3 Wang Labs

        Just because I like to use the word "Wang" (script kiddies born after 1980 won't have a clue what it really is).


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