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Re: [dhcwg] [homenet] What to do when we lose DHCPv4 election?

"Bernie Volz (volz)" <volz@cisco.com> Fri, 21 August 2015 16:55 UTC

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From: "Bernie Volz (volz)" <volz@cisco.com>
To: Juliusz Chroboczek <jch@pps.univ-paris-diderot.fr>, Michael Richardson <mcr+ietf@sandelman.ca>
Thread-Topic: [dhcwg] [homenet] What to do when we lose DHCPv4 election?
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Date: Fri, 21 Aug 2015 16:55:39 +0000
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Cc: dhcwg <dhcwg@ietf.org>, Homenet <homenet@ietf.org>
Subject: Re: [dhcwg] [homenet] What to do when we lose DHCPv4 election?
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Typically a server would grant the requested address in the DHCPREQUEST unless there was a reason it could not, for example:
- Address is no longer valid for the network segment
- Address is in use by another device

It is probably best NOT to NAK something unless there is a good reason to.

Note: The DHCPREQUEST here would most likely end up being a INIT-REBOOT or a REBIND -- RENEWs are unicast to the server so those might not be seen (unless the DHCP server has been replaced with a device at the same address - in which case, the above policy works nicely).

- Bernie

-----Original Message-----
From: dhcwg [mailto:dhcwg-bounces@ietf.org] On Behalf Of Juliusz Chroboczek
Sent: Monday, August 17, 2015 6:26 AM
To: Michael Richardson
Cc: dhcwg; Homenet
Subject: Re: [dhcwg] [homenet] What to do when we lose DHCPv4 election?

>> 2. remain silent in response to DHCPDISCOVER, but NAK any 
>> DHCPREQUEST; or

> I think that #2 is probably correct, but I have two questions.

By the way, if some Wise Person were kind enough to check my DHCPv4 server for compliance, I'd be very grateful.  The code is here:

    https://github.com/jech/shncpd/blob/master/dhcpv4.c#L663

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