Re: [dhcwg] AD Evaluation: draft-ietf-dhc-dhcpv6-unknown-msg

Tomek Mrugalski <> Sun, 02 February 2014 15:07 UTC

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Date: Sun, 02 Feb 2014 17:07:50 +0100
From: Tomek Mrugalski <>
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Subject: Re: [dhcwg] AD Evaluation: draft-ietf-dhc-dhcpv6-unknown-msg
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On 02.02.2014 14:33, Ted Lemon wrote:
>> 5. Also from Ralph... Could section 5 simply be written as "A client or
>> server MUST silently discard any received DHCPv6 message with an unknown
>> message type."?
> Yes, I think this is a good edit.
I would extend the text a bit with "The server or client MAY log the
fact.". Silently dropping a message that is typically network setup
problem may hide problems and make their debugging harder.

If you configured your relay to send message X, but your server is not
capable of understanding it, then why did you configure your relay to
send it in the first place? Also, if your network has clients that send
message Y and your server does not know what to do with it, perhaps its
time upgrade your server? Or forbid those particular clients if that new
behavior is not welcome in a given network.

On the other hand, some people may afraid that their server could be
spammed with messages of bogus type and filling in syslog with useless
junk. Given those two arguments, MAY seems like a good compromise for
the logging.