Re: [core] Stateless proxy and 5.04 (Gateway Timeout)

Christian Amsüss <christian@amsuess.com> Fri, 22 November 2019 08:53 UTC

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Date: Fri, 22 Nov 2019 09:53:01 +0100
From: Christian Amsüss <christian@amsuess.com>
To: Carsten Bormann <cabo@tzi.org>
Cc: Klaus Hartke <hartke@projectcool.de>, Christer Holmberg <christer.holmberg=40ericsson.com@dmarc.ietf.org>, "core@ietf.org" <core@ietf.org>
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Subject: Re: [core] Stateless proxy and 5.04 (Gateway Timeout)
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On Thu, Nov 21, 2019 at 07:17:56PM +0800, Carsten Bormann wrote:
> >   If the request to the destination times out, then a 5.04 (Gateway
> >   Timeout) response MUST be returned.
> 
> How can the request time out if the proxy has forgotten all about it?
> 
> In this case, the timeout cannot be anything but infinite.

A more precise definition of "times out" might have been "if the proxy
decides to discard any state it had to hold about the request". For a
stateless proxy, that won't happen.

(A stateless proxy might have an LRU cache of origin server for which it
keeps per-server state, but a server falling out of that should not
impede the forwardability of responses).

Best regards
Christian

-- 
I shouldn't have written all those tank programs.
  -- Kevin Flynn