[squid-users] Re: Question about Expires header and TCP_REFRESH_HIT

From: Piotr Ślatała <dokosza_at_sepio.pl>
Date: Mon, 15 Sep 2008 09:42:21 +0200 (CEST)

Hi,
it's me again. Due to the fact, that no one responded to this email, I
will resend it.. If I wasn't clear in stating a problem, please write me,
I will try to explain it again. I just don't know how to force squid to
change expires header after receiving 304 not modified from server ... :(

Regards,
Peter
> Hi,
> I'm using: Squid Cache: Version 2.6.STABLE13
>
> I'm caching in accelerator mode(or should I say - reverse proxy), for
> example pictures, with 6hours expiry time. After this time, I'd like cache
> to check newer versions. I use refresh_pattern:
>
> refresh_pattern -i \.gif$ 60 90% 720 override-expire override-lastmod
> ignore-reload
>
> I've been also trying without override-expire(and lastmod). The problem
> is, after 6 hours, cache do invalidate its content, but receives 304 Not
> Modified from server and doesn't change expires date:
> 1220889578.703 10 83.31.43.112 TCP_REFRESH_HIT/200 1538 GET
> http://mypage/mypicture.gif - FIRST_UP_PARENT/front2 image/gif
>
> Today, 2008-09-09, I have in headers:
> http://mypage/mypicture.gif
>
> GET /mypicture.gif HTTP/1.1
> Host: mypage
> User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; pl; rv:1.8.1.16)
> Gecko/20080702 Firefox/2.0.0.16
> Accept:
> text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
> Accept-Language: pl,en-us;q=0.7,en;q=0.3
> Accept-Encoding: gzip,deflate
> Accept-Charset: ISO-8859-2,utf-8;q=0.7,*;q=0.7
> Keep-Alive: 300
> Connection: keep-alive
> If-Modified-Since: Fri, 05 Sep 2008 06:49:18 GMT
> If-None-Match: "613727-77eff780"
>
> HTTP/1.x 304 Not Modified
> Date: Fri, 05 Sep 2008 07:56:18 GMT
> Content-Type: image/gif
> Expires: Fri, 05 Sep 2008 13:56:18 GMT
> Last-Modified: Fri, 05 Sep 2008 06:49:18 GMT
> Etag: "613727-77eff780"
> Age: 15380
> X-Cache: HIT from mypage
> X-Cache-Lookup: HIT from mypage:3128
> Via: 1.0 mypage:3128 (squid/2.6.STABLE13)
> Connection: keep-alive
> ----------------------------------------------------------
>
> Especially:
> Date: Fri, 05 Sep 2008 07:56:18 GMT
> Expires: Fri, 05 Sep 2008 13:56:18 GMT
> Expires is 6 hours after Date, as You can see, but, today we have
> 2008-09-09 :) When I turn off the squid, I also receive 304 Not Modified,
> but with valid expiry time:
>
> http://mypage/mypicture.gif
>
> GET /mypicture.gif HTTP/1.1
> Host: mypage
> User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; pl; rv:1.8.1.16)
> Gecko/20080702 Firefox/2.0.0.16
> Accept:
> text/xml,application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
> Accept-Language: pl,en-us;q=0.7,en;q=0.3
> Accept-Encoding: gzip,deflate
> Accept-Charset: ISO-8859-2,utf-8;q=0.7,*;q=0.7
> Keep-Alive: 300
> Connection: keep-alive
> If-Modified-Since: Fri, 05 Sep 2008 06:49:18 GMT
> If-None-Match: "613727-77eff780"
>
> HTTP/1.x 304 Not Modified
> Date: Tue, 09 Sep 2008 08:52:24 GMT
> Server: Apache
> Connection: Keep-Alive
> Keep-Alive: timeout=5, max=500
> Etag: "613727-77eff780"
> Expires: Tue, 09 Sep 2008 14:52:24 GMT
> Cache-Control: max-age=21600, must-revalidate
> ----------------------------------------------------------
>
>
> Do You have any idea why it behaves this way? I found something similar:
> http://www1.uk.squid-cache.org/mail-archive/squid-users/200602/0305.html
> but this topic has no clues. How can I force squid to change expiry time?
> Is there any other way, than disabling 304 in Apache?
>
> Best Regards,
> Peter
>
>

-- 
Usługi fotograficzne i komputerowe
Piotr Ślatała
email: piotr_at_sepio.pl
tel.:  503 529 929
WWW:   http://sepio.pl
Received on Mon Sep 15 2008 - 07:42:31 MDT

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