Subject: Re: /dev/tap and tcpdump don't go together very well?
To: Johnny Billquist <>
From: Perry E. Metzger <>
List: current-users
Date: 04/09/2007 14:01:04
Johnny Billquist <> writes:
> Are there any way, or plans to be able to, change the mac address of
> an ethernet interface in NetBSD? I don't think there is, but I might
> have missed something.

Someone posted patches a long time ago to do that (adding an ioctl and
a hook in ifconfig(8)), but they got yelled at because there was a
proposal to "do it better" which was never implemented. Much later, I
needed to do this (because I had two machines that arrived with the
same MAC address) and I asked if I could commit the code, but after a
long time no one made any decision on the subject and I gave up.

The patches to do this the straightforward way are quite simple. You
can find the code in the archives (and possibly in the PR database, I
can't remember if it is there as well or not.) It would be a good
thing if they finally got committed, if only until such time in the
distant future when the "perfect" way gets coded.