Re: changing MAC address

[bozo () SZIVARVANYNET HU (Borbely Zoltan)]

On Thu, Mar 30, 2000 at 12:21:12PM +0200, Antonio Fernandes Vazquez wrote:
> On Wed, 29 Mar 2000, Arturo Busleiman wrote:
>
> > This is question regarding an old thread.
> >
> > > as an example, under linux, as root:
> > >
> > >   ifconfig eth0 hw ether 00:aa:23:ce:3a:11
> > >
> > > changes the mac address of eth0 to 00:aa:23:ce:3a:11, iirc.
> >
> >         [root@machine /root]# ifconfig eth0 hw ether 00:aa:23:ce:3a:11
> >         SIOCSIFHWADDR: Device or resource busy
> >
> > why does this happen? under which circumstances can I use ifconfig for
> > that purpose?
> I'm not totally sure that this purpose with ifconfig will works in every
> ethernet card, i think that in major this info is written into an ROM.
> I try to set down the interface and after change it, but not possible in
> my case, you can read more about this in hacking () argo es. ;)

I think most of the ethernet cards are capable to change their mac address.
If I remember correctly we have to thank this to DEC :-) The DECnet protocol
family isn't contain a helper protocol like ARP, so the area and node
address are coded into the ethernet address. So if the mac address of a
card can't be changed it can't use decnet...

In this example maybe the driver doesn't support SIOCSIFHWADDR ioctl...

Zoltan BORBELY