[163324] in North American Network Operators' Group
Re: IP4 address conservation method
daemon@ATHENA.MIT.EDU (William Herrin)
Wed Jun 5 12:31:33 2013
In-Reply-To: <alpine.DEB.2.00.1306051810240.12285@uplift.swm.pp.se>
From: William Herrin <bill@herrin.us>
Date: Wed, 5 Jun 2013 12:30:33 -0400
To: Mikael Abrahamsson <swmike@swm.pp.se>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Wed, Jun 5, 2013 at 12:11 PM, Mikael Abrahamsson <swmike@swm.pp.se> wrote:
> On Wed, 5 Jun 2013, William Herrin wrote:
>> Both the router and host have to support sending and accepting invalid ARP
>> requests. Since the Linux kernel already mishandles arp by default, you're
>> probably begging for unexpected behavior. Double down on that if the
>> customer controls the server image.
>
> Exactly what is wrong with the ARP answers and requests sent using
> local-proxy-arp?
Nothing. The problem is that the arp source IP doesn't fall within the
interface netmask at the receiver. Some receivers ignore that... after
all, why do they care what the source IP is? They only care about the
source MAC. Other receivers see a spoofed packet and drop it.
Regards,
Bill Herrin
--
William D. Herrin ................ herrin@dirtside.com bill@herrin.us
3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
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