From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [Bugme-new] [Bug 6610] New: dummy interface broadcast
 destination hardware address is not ff:ff:ff:ff:ff:ff
Date: Thu, 25 May 2006 18:18:13 -0700 (PDT)
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To: herbert@gondor.apana.org.au
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From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Fri, 26 May 2006 10:43:24 +1000

> On Thu, May 25, 2006 at 03:16:02PM -0700, David Miller wrote:
> > 
> > Perhaps RTN_BROADCAST should take precedence over IFF_NOARP
> > (but not IFF_LOOPBACK)?  I'm talking about the code in
> > net/ipv4/arp.c that causes this behavior.
> 
> Sure, I don't see any harm in that.
> 
> However, I'm curious as to the purpose of all this.  What application
> is there for sending broadcasts through a dummy device with the
> Ethernet broadcast address?

Good point.  dummy is just a black hole to point routes to
while your real connection is down.

Running tcpdump on it and having any kind of expectations
about broadcast addresses and whatnot is pointless.