IP4 address conservation method

William Herrin bill at herrin.us
Wed Jun 5 16:30:33 UTC 2013


On Wed, Jun 5, 2013 at 12:11 PM, Mikael Abrahamsson <swmike at 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 at dirtside.com  bill at herrin.us
3005 Crane Dr. ...................... Web: <http://bill.herrin.us/>
Falls Church, VA 22042-3004




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