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Re: TCP and IPV6_USE_MINMTU

Brian E Carpenter <brian.e.carpenter@gmail.com> Fri, 16 October 2015 22:35 UTC

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Subject: Re: TCP and IPV6_USE_MINMTU
To: Mark Andrews <marka@isc.org>, John Leslie <john@jlc.net>
References: <20151016034110.306563A939AB@rock.dv.isc.org> <20151016202620.GI1442@verdi> <20151016203155.3D2473AA8817@rock.dv.isc.org>
From: Brian E Carpenter <brian.e.carpenter@gmail.com>
Organization: University of Auckland
Message-ID: <56217BAB.2040608@gmail.com>
Date: Sat, 17 Oct 2015 11:35:23 +1300
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On 17/10/2015 09:31, Mark Andrews wrote:
> 
> In message <20151016202620.GI1442@verdi>, John Leslie writes:
>> Mark Andrews <marka@isc.org> wrote:
>>>
>>> Please see
>>> https://www.ietf.org/id/draft-andrews-tcp-and-ipv6-use-minmtu-00.txt
>>>
>>> It addresses what should be obviously done but isn't by many
>>> implementations.
>>
>>    Alas, this draft gives no clue _how_ to check IPV6_USE_MINMTU ...
>> (or, for that matter, how to set it).
>>
>>    One could reasonably guess that s/he should look through RFC3542 to
>> find how to check this; but RFC3542 contains no such string. (It does
>> contain the string IPV6_USE_MIN_MTU; but I don't feel justified in
>> guessing that far astream...

Incidentally, it recently came to my attention that standard Python
doesn't support RFC3542. I don't know how widespread that issue is, but
it may be behind some of these broken MSS deployments.

    Brian


> 
> Yes, I typo'd that, repeatedly.
>  
>>    Perhaps adding a citation to the specific section of a particular
>> RFC would help?
>>
>> --
>> John Leslie <john@jlc.net>

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