Re: [v6ops] Some stats on IPv6 fragments and EH filtering on the Internet

Mikael Abrahamsson <swmike@swm.pp.se> Tue, 05 November 2013 02:21 UTC

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Date: Tue, 5 Nov 2013 03:20:54 +0100 (CET)
From: Mikael Abrahamsson <swmike@swm.pp.se>
To: Fernando Gont <fernando@gont.com.ar>
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Subject: Re: [v6ops] Some stats on IPv6 fragments and EH filtering on the Internet
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On Mon, 4 Nov 2013, Fernando Gont wrote:

> I guess we didn't have a good success rate with ICMP{v4,v6} filtering 
> for PMTUD to be reliable?

I have to oppose to this one as well. Filtering means intent (right?). 
Lots of PMTUD problems are not intentional, they are caused by other 
reasons, like L2 MTU mismatch on links so packets are dropped silently 
without the operator noticing. Some are also caused by misconfigured load 
balancers etc (the ICMP message is lost due to bad implementation, not due 
to active decision to filter).

-- 
Mikael Abrahamsson    email: swmike@swm.pp.se