Re: Strange Network behavior

A.N.Kuznetsov (
Sat, 26 Jul 1997 20:00:31 +0400 (MSD)


> Why would a Linux machine with no `known` network activity even care about
> ARPing these addresses? It seems real strange.
> IP HW 00:00:0C:0A:3E:D3

They should expire after ~5 minutes of inactivity.
If the host really exists it costs nothing, arp pings
are not broadcasted. Besides that, in released version
ping interval is set to huge value ~5min, it will expire
before the first useless ping.

> unknown host IP HW 00:00:00:00:00:00

Really dead addresses are real problem: it means that every
1 min your host tries to resolve
Well, it also will expire after normal cache timeout.

You could declare these addresses as broadcasts, but
you need iproute utility:

iproute add dev eth0 local broadcast

What's about these unexpected broadcast addresses, it is real bug,
though it is harmless. Your router will never forward such packets,
if they are received as link level broadcasts, but routing cache
does not know that they are broadcasts and tries to maintain
path to them. It is harmless, but wrong. I'll fix it, thank you
for information.

Alexey Kuznetsov.