Subject: Re: dhcp(8) _cannot_ be completely disabled on an interface
To: David Laight <>
From: Andrew Brown <>
List: tech-net
Date: 01/12/2002 11:06:04
>> i was thinking of the link layer address.  there's currently no way to
>> get that from the network layer in the kernel on a per-packet basis,
>> unlike, say, the receiving ip address.
>What makes you think the link layer address is unique?

because it has to be?

>It only needs to be unique on a (bridged) LAN segment.

there, like that.

>Indeed some of the sBus ethernet cards sold by sun do not have a MAC
>address PROM.  The solaris driver (and I assume the netbsd one) uses
>the system mac address for these add-on cards.

sure, i knew that.  suns (by default) take the top three octets of the
mac address from the prefix assigned to them by sun, who gets it from
iee, i suppose) and the bottom three from the hostid and use the same
mac address on each physical interface.  typically, there should be no
reason not to.  in practice, however, i don't like it, so i set this:


and it uses the mac address from the interface, not the constructed

|-----< "CODE WARRIOR" >-----|             * "ah!  i see you have the internet (Andrew Brown)                that goes *ping*!"       * "information is power -- share the wealth."