Subject: Re: netstat -i
To: Martin Konold <zxmmz01@fiwi02.wiwi.uni-tuebingen.de>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: tech-kern
Date: 06/26/1996 17:56:35
On Wed, 26 Jun 1996 23:34:23 +0200
Martin Konold <zxmmz01@fiwi02.wiwi.uni-tuebingen.de> wrote:
> Name Mtu Network Address Ipkts Ierrs Opkts Oerrs Coll
> le0 1500 <Link> 8.0.9.15.65.54 78186 0 97958 0 1210
...this is the "link level" address. The address is the ethernet (MAC)
address of the interface.
> le0 1500 134.2.170 centauri.tat.phys 78186 0 97958 0 1210
This is the IP subnet and address of the interface.
> What I would like to know (any pointers to documentaion) is:
>
> What is special about 8.0.9.15.65.54?
>
> Why are there two entries for the single ethernet device?
See above :-)
> Is there done any copying inside the kernel?
There is some copying done ... firstly, the data is copied from the card
into an mbuf chain. If there is a bpf listener, a copy of the packet is
made for it. There are other cases where the data might be copied, but
there is an attempt to keep this to a minimum.
> Where may I optain technical information about the *BSD kernels and
> networking?
The Design and Implementation of the 4.4BSD Operating System is a good
book, and has a good sized chunk on the networking subsystem.
-- save the ancient forests - http://www.bayarea.net/~thorpej/forest/ --
Jason R. Thorpe thorpej@nas.nasa.gov
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