Some requests not getting logged

[Jonathan Matthews]

On 18 September 2012 07:46, Maxim Dounin <mdounin at mdounin.ru> wrote:
> On Mon, Sep 17, 2012 at 07:38:49PM -0400, eiji-gravion wrote:
>> I've noticed that some (seemingly random) requests get logged as 400 and 408
>> codes without 301 or 200 codes showing up in the logs.
>>
>> This seems to occur a lot when redirecting people from http > https via a
>> 301 redirect, the 301 redirect will in many cases not appear at all in the
>> logs but will instead show the following after some time has passed:
>>
>> - - 24.**.***.** - - [17/Sep/2012:19:19:07 -0400] "-" 400 0 "-" "-" "-" "-"
>>
>> I've also seen some https requests not show up in the logs at all as 200
>> codes, but will eventually display 408 codes:
>>
>> TLSv1 ECDHE-RSA-RC4-SHA 213.***.***.** - - [17/Sep/2012:18:30:31 -0400] "-"
>> 408 0 "-" "-" "-" "-"
>>
> Most likely this is a result of a cached response being used by a
> browser, while in logs you see only a connection which was open by
> the browser but no requests were sent in it.

I agree. I believe we already covered this here on the list a while
ago, didn't we?

I seem to recall it's caused by UAs optimistically opening (multiple?)
connections to origin servers, and then closing them after they go
unused. I.e. with no data transferred (i.e. 400/408 depending on
protocol).

I suspect you see these at HTTP->HTTPS redirection as that's the point
at which the UA notices that it's no longer accessing the HTTP://site/
, and closes the unused/cached/fallow optimistic HTTP connections it
had opened in /case/ the user continued browsing over HTTP.

My 2 cents,
Jonathan
--
Jonathan Matthews
Oxford, London, UK
http://www.jpluscplusm.com/contact.html