Re: Interesting question!

Ok, I can't resist writing more than one sentence. The reason why you
have to disable proxy arp is because an end station with no default
gateway (pretty much what they have done) will send out arp requests to
any ip it needs to talk to. So instead of the IP's that it has deemed
remote from it's subnet mask it will arp for everything. Proxy arp just
tells the router to send out arp replies for addresses that it has routes
to in order to support this behavior. Two things bother me about this
question. One is that the users in the question don't actually gain much
redundancy by doing this if there is only one router on the subnet. The
other is that they can (tedious I know) create static arp mappings for the
router's mac address if you disable proxy arp. That being said no proxy
arp sounds like the answer they wanted.

From:
hopalong <ccieangel_at_googlemail.com>
To:
Cisco certification <ccielab_at_groupstudy.com>
Date:
07/16/2009 11:35 AM
Subject:
Interesting question!
Sent by:
nobody_at_groupstudy.com

Hi

I kinda got this question which is puzzling me :)

It goes a bit like this,

'some users on a LAN have set their default-gateway to point to their own
IP
address instead of the connected router, in order to gain some redundancy.
Configure said router not to support these guys'

How would you go about answering this?

Thanks!

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Received on Thu Jul 16 2009 - 12:57:57 ART