Re: [dhcwg] Change in server identifier between OFFER and ACK

Andre Kostur <akostur@incognito.com> Mon, 10 June 2013 14:00 UTC

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Date: Mon, 10 Jun 2013 06:59:57 -0700
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From: Andre Kostur <akostur@incognito.com>
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Subject: Re: [dhcwg] Change in server identifier between OFFER and ACK
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I suppose if you looked between the lines hard enough, you can see it
in 2131, Section 4.4.1: "Once the DHCPACK message from the server
arrives....".   From the client perspective, it's not the same server
if the Server ID is different.

>From a more intuitive standpoint, I would expect the client to ignore
it.  A server that isn't the one that the client has selected is
attempting to answer.  Ignore the response.  Wait for the normal
timeout and rebroadcast your REQUEST in the hopes that the server that
you did select answers you.  If that server really wanted to give me
an address, why didn't I see the OFFER that came from that server?

On Sun, Jun 9, 2013 at 6:07 AM, gvithal . <gvithal@gmail.com> wrote:
> As per the standard, is it valid scenario for server identifier to change
> between OFFER and ACK for the same transaction id (i.e. for the same DORA
> transaction).
> If the server identifier changes between OFFER and ACK, what is the expected
> client behaviour.
> There does not seem to be any text in RFC 2131 related to this scenario.
>
> Thanks,
> Prasad
>
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