On Jan 29, 2014, at 3:22 PM, Tim Traver <[email protected]> wrote:
> Hi all,
>
> HTTP/1.1 200 OK
> Date: Wed, 29 Jan 2014 22:15:08 GMT
> Server: ATS/4.1.2
> Last-Modified: Wed, 02 Oct 2013 22:15:10 GMT
> ETag: "14e57-4e7c9670a1780"
> Accept-Ranges: bytes
> Content-Length: 85591
> X-Powered-By: PleskLin
> P3P: CP="NOI DEVa TAIa OUR BUS UNI STA"
> Content-Type: image/png
> Age: 26
> Connection: keep-alive
> Via: http/1.1 scotte6 (ApacheTrafficServer/4.1.2 [uScMsSf
> pSeN:t cCMi p sS])
>
>
Well, assuming you are using default configurations (which requires an Expires:
or Cache-Control: max-age= … header), the above is not cacheable. However, the
Age: 26 seems to imply something cached this, how do you know this is not
cached? The above is cacheable, if you have changed records.config to
CONFIG proxy.config.http.cache.required_headers INT 1
(since there is a Last-Modified in the response).
To debug, If you send e.g.
curl -D - -o /dev/null -s -H “Cache-Control: only-if-cached”
http://some_url.com/foo.png
then if it’s a cache miss, you’ll get a 504, vs a 200 OK on a cache hit.
Next, the request header you show us is designed to bust all caches. By
default, ATS follows the RFC 2616 protocol, and allows the client to do so, but
you can disable that by making sure the following configuration is set:
CONFIG proxy.config.http.cache.ignore_client_cc_max_age INT 1
Finally, a problem could be the old issue related to how we handled the various
accept headers. You could try to set (this works since you are using 4.1.2):
CONFIG proxy.config.http.cache.ignore_accept_mismatch INT 2
CONFIG proxy.config.http.cache.ignore_accept_language_mismatch INT 2
CONFIG proxy.config.http.cache.ignore_accept_encoding_mismatch INT 2
CONFIG proxy.config.http.cache.ignore_accept_charset_mismatch INT 2
These are safe to set in v4.1.2 and later with a value of “2”, whereas a value
of “1” can break sites if they intend to Vary: on the respective header. The
default is off currently, but we plan on making them set to “2” in 5.0.0. While
we’re at it, make sure this is also set (it’s the default);
CONFIG proxy.config.http.normalize_ae_gzip INT 1
I hope this helps.
— Leif
