Henrik helped me with an issue we had with another proxy, a bluecoat sg200, requesting documents from our reverse proxy squid. See thread "bluecoat proxying to squid". We now have another issue whereby the bluecoat will occasionally not cache documents because it seems to think they have already expired, and the squid gets every request that comes in as the bluecoat is constantly doing a cache MISS. Its an intermittent problem, sometimes the file will be cached correctly on the bluecoat, sometimes not. At all times the file is cached correctly on squid. We have the "act-as-origin" feature enabled from latest squid cvs sources, to update Date: and Expires: headers. I also removed the X-Origin- Expires and X-Origin-Date headers in case they caused the issue. e.g. request from bluecoat: GET /Images/football/badges/13x13/b_7.png HTTP/1.1 If-None-Match: "12932d-367-46af1eb9" Host: www.myhost.com Cookie: CP=null*; Apache=192.168.50.144.166481185975779307 Accept: */* Referer: http://www.myhost.com/blah/blah/0,,11660,00.html Accept-Language: en-gb User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1) X-Forwarded-For: 10.160.21.76 Via: 1.0 NETCACHE01 (NetCache NetApp/5.5R6D25) Cache-Control: max-stale=0 Connection: Keep-Alive X-BlueCoat-Via: BD4F8D1E42E65ECB and squid response: HTTP/1.0 200 OK Date: Tue, 07 Aug 2007 12:07:06 GMT Expires: Tue, 07 Aug 2007 13:07:06 GMT Server: Apache/1.3.37 (Unix) Cache-Control: public, s-maxage=3600, max-age=3600 Last-Modified: Tue, 31 Jul 2007 11:36:25 GMT ETag: "12790b-367-46af1eb9" Accept-Ranges: bytes Content-Length: 871 Content-Type: image/png X-Cache: HIT from mysquid Via: 1.0 mysquid:80 (squid/2.HEAD-CVS) Connection: keep-alive The bluecoat should be using the Expires: and Cache-Control: headers to cache that image for 1 hour, and not make any more requests for it until it expires, but the requests keep coming in. Anybody seen this behaviour before ? Henrik perhaps you know of some issue with squid again? Thanks, -- Michael
