On Tue, 28 Nov 2006 11:01:20 -0800
"Tim Wright" <[EMAIL PROTECTED]> wrote:

> Hi folks,
> I have been tracking down a strange problem, and have a simple
> "reproduce-by" and was looking for opinions from those better-versed in
> the networking code. Basically, it is possible to get a system into a
> state where it responds to ARP requests even though no interface has the
> address requested. Here is a simple reproduce-by:
> 
> Select and address in the same subnet as eth0
> # ifconfig eth0:5 W.X.Y.Z netmask ... up
> This works. Machine now responds to arp requests for W.X.Y.Z.
> # ifconfig eth0:6 W.X.Y.Z netmask ... up
> This fails as it should. But, the damage is done.
> # ifconfig
> You will only see eth0 and eth0:5. There is no eth0:6 interface. Good.
> # ifconfig eth0:5 down
> Now we are supposedly back to the original state. BUT the machine will
> still respond to ARP requests for W.X.Y.Z
> 
> The easiest way to get out of this is to bring up eth0:5 again, and
> bring it down again. However, this looks to me like the undo code when a
> clashing address is found fails to clean up the arp side of things
> correctly. Any clues here?
> 
> Please copy me on any responses. I am not on the linux-net mailing list.
> 
> Thanks very much,

This is a common confusion. Read the mailing list archives. Linux
associates IP address with system not interface, so it will respond
to ARP for any of the IP addresses on any interface.
-
To unsubscribe from this list: send the line "unsubscribe linux-net" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to