I see you are using Apache 2.0.46. I seem to remember that there once was a bug in mod_cache causing stale entries not to be replaced in certain versions of Apache 2.0. Apache 2.0.46 may be one of the versions affected by this problem. That would cause the cache provider to decline to serve the response for every single request after the cached response has expired, which would be consistent with the fact that responses (including 304) are consistently served by the back end after the cached response has expired. You should be able to verify this behaviour by - set LogLevel debug, - flushing the cache (by removing everything under the cache root, and possibly restarting Apache if your are using memory caching), - request a short lived cacheable element, - verify that subsequent responses are server by cache, - wait till the cache response expires, - request the same short-lived cacheable element, - observe the debug trace in the error log - request the same short-lived cacheable element (is it served from cache or does the provider still say it is stale ??) I know for sure that this particular problem does not exist in Apache 2.0.54. I suspect it was corrected prior to the release of 2.0.49. -ascs -----Original Message----- From: Matthew Claridge [mailto:mclaridge@xxxxxxxxxxxxx] Sent: Wednesday, June 07, 2006 10:17 AM To: users@xxxxxxxxxxxxxxxx Subject: Re: [users@httpd] Image caching / Expiry times / 304s Ok, there are two things going on here, one of which I'll hang my head in shame for :-( Firstly, the correct Cache-Control header is sent for the initial 200 response on these files - so what would prevent it from being sent only on 304 responses? Secondly, the /Cache-Control max-age=0/ header I mentioned earlier is in the REQUEST header, not the server's response header! Seems I can't read properly! To clarify, these are the request and response headers for an initial request for an image and then a subsequent request where the image is cached: Host=www.highandwild.co.uk User-Agent=Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.4) Gecko/20060508 Firefox/1.5.0.4 Accept=image/png,*/*;q=0.5 Accept-Language=en,en-us;q=0.5 Accept-Encoding=gzip,deflate Accept-Charset=ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive=300 Connection=keep-alive Referer=http://www.highandwild.co.uk/ Cookie=KMVisitor=10606061024500283146 Pragma=no-cache Cache-Control=no-cache Status=OK - 200 Date=Wed, 07 Jun 2006 08:10:57 GMT Server=Apache/2.0.46 (Red Hat) Last-Modified=Wed, 07 Jun 2006 08:05:00 GMT Etag="85c0a2-f79-d2f28300" Accept-Ranges=bytes Content-Length=3961 Cache-Control=max-age=432000 Expires=Mon, 12 Jun 2006 08:10:57 GMT Connection=close Content-Type=image/jpeg Host=www.highandwild.co.uk User-Agent=Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.0.4) Gecko/20060508 Firefox/1.5.0.4 Accept=image/png,*/*;q=0.5 Accept-Language=en,en-us;q=0.5 Accept-Encoding=gzip,deflate Accept-Charset=ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive=300 Connection=keep-alive Referer=http://www.highandwild.co.uk/ Cookie=KMVisitor=10606061024500283146 If-Modified-Since=Wed, 07 Jun 2006 08:05:00 GMT If-None-Match="85c0a2-f79-d2f28300" Cache-Control=max-age=0 Status=Not Modified - 304 Date=Wed, 07 Jun 2006 08:16:21 GMT Server=Apache/2.0.46 (Red Hat) Connection=close Etag="85c0a2-f79-d2f28300" --------------------------------------------------------------------- The official User-To-User support forum of the Apache HTTP Server Project. See <URL:http://httpd.apache.org/userslist.html> for more info. To unsubscribe, e-mail: users-unsubscribe@xxxxxxxxxxxxxxxx " from the digest: users-digest-unsubscribe@xxxxxxxxxxxxxxxx For additional commands, e-mail: users-help@xxxxxxxxxxxxxxxx
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