system-config-network & Zeroconf

[Lennart Poettering]

On Thu, 06.03.08 13:51, John W. Linville (linville at redhat.com) wrote:

> > I'm sorry, but that's just wrong. Setting a net route on a broadcast
> > device will cause ARP request for the IP addresses in that network
> > to be broadcast on that segment. Nothing more, nothing less. A host has
> > to respond to these requests for routing to occur (most likely though
> > proxy arp). The only thing being sent with a broadcast MAC are the ARP
> > requests, but those are always sent this way.
> 
> Ralf is, of course, correct. [1]  In a sense the only purpose of
> the routing table is to control which IP address gets ARPed when
> sending-out a frame.  Setting the default route to "dev eth0" just
> means you ARP for any address.
> 
> Just to make sure, I replicated this environment on my local LAN.
> Simply setting the default route as "dev eth0" left me with a laptop
> that could only reach the local LAN.  Turning on proxy arp at my NAT
> router enabled me to communicate with the Internet.  I encourage you
> to replicate my experiment. :-)
> 
> It's possible that there is some other setting that turns-on the
> behavior you describe.  But if there is, I don't know about it.
> 
> Thanks,
> 
> John
> 
> [1] Conveniently, that means I am correct as well. :-)

Of course, you two are absolutely correct. My bad. I guess I shouldn't
claim things without checking them first ;-)

But still, enabling this kind of routing on the gateway is just a
matter of doing:

echo 1 > /proc/sys/net/ipv4/conf/eth0/proxy_arp
echo 1 > /proc/sys/net/ipv4/conf/eth0/forwarding

Right?

Lennart

-- 
Lennart Poettering                        Red Hat, Inc.
lennart [at] poettering [dot] net         ICQ# 11060553
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