Re: H2 Implementation Debug State URI

Alex Rousskov <rousskov@measurement-factory.com> Fri, 05 August 2016 16:08 UTC

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References: <63CCB07A-0204-4CF7-B598-9497D7112021@lukasa.co.uk> <4314.1470384112@critter.freebsd.dk> <B4171FD2-B154-4950-BF0C-4B5A4714367F@lukasa.co.uk>
Cc: Cory Benfield <cory@lukasa.co.uk>
From: Alex Rousskov <rousskov@measurement-factory.com>
To: HTTP Working Group <ietf-http-wg@w3.org>
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Date: Fri, 05 Aug 2016 10:00:32 -0600
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Subject: Re: H2 Implementation Debug State URI
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On 08/05/2016 03:07 AM, Cory Benfield wrote:

> The longer term question is about how to deal with the fact that a
> misbehaving H2 connection could be the result of the H2 state in any of
> the hops on the connection. For example, if you have a connection that
> goes: client -> forward proxy A -> reverse proxy B -> origin server, and
> all those hops are H2, you really need to see H2 state in *all* of them
> to understand what the problem might be. However, the well-known URI
> doesn’t allow for that kind of debugging without requiring the awkward
> step of needing proxies to rewrite the response body to include their
> own data.

If you combine the well-known debugging URI with a Max-Forwards header,
then you may get pretty close to the desired "and here is my state too"
effect. It is not going to be "the state of each agent at the same
moment of time", but nothing is going to give you that precision anyway.

Alex.