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Date: Sun, 01 Jun 2014 08:24:48 +0200 (CEST)
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To: john@thehowies.com
Subject: Re: Patches for BOOTP/DHCP code to support Windows Server DHCP
From: sthaug@nethelp.no
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> Section 3.5 of RFC 2131 (the DHCP RFC) states that "...Second, in its
> initial DHCPDISCOVER or DHCPREQUEST message, a client may provide the
> server with a list of specific parameters the client is interested in"
> and "...The client can inform the server which configuration parameters
> the client is interested in by including the 'parameter request list'
> option."  The data portion of this option explicitly lists the options
> requested by tag number. A DHCP Server is not required to return any
> parameter that a client does not ask for. It appears that the ISC-DHCP
> server, which is recommended by most, will return configured options
> regardless of whether or not the client asks for them.

As far as I know this is wrong. ISC DHCP does *not* behave this way.
Do you have packet sniffer traces to indicate oterwise?

In any case - yes, the client should absolutely request all the
parameters it wants.

Steinar Haug, Nethelp consulting, sthaug@nethelp.no