Re: [squid-users] How to make squid proxy server cache response with vary: * in header?

"Vary:*" means the response changes depending on factors outside the
HTTP protocol for which shared proxies like Squid are 100% unable to
determine whether the cached response is appropriate to deliver.
 Even if you did store it, the cache would still always MISS.

FWIW: The server for stackoverflow is presenting several conflicting
cache controls. Personally I think that server should be emitting an
ETag header and Cache-Control:max-age=60 instead of the Vary and the
Cache-Control's it is using. But even so there is still nothing any
proxy can do about it except MISS.

Also, be aware that curl by default sends cache control headers forcing
a MISS, so it is not the best tool to be testing proxies with. Prefer
wget, squidclient, or the HTTP validator at http://redbot.org/.

Amos

On 8/04/2014 2:00 p.m., Sylvio Cesar wrote:
> curl -x localhost:3128 --silent -o /dev/null --dump-header /dev/stdout
> http://stackoverflow.com
> HTTP/1.1 200 OK
> Cache-Control: public, max-age=18
> Content-Type: text/html; charset=utf-8
> Expires: Tue, 08 Apr 2014 02:00:38 GMT
> Last-Modified: Tue, 08 Apr 2014 01:59:38 GMT
> Vary: *
> X-Frame-Options: SAMEORIGIN
> Date: Tue, 08 Apr 2014 02:00:18 GMT
> Content-Length: 212147
> X-Cache: MISS from sylviosuse11
> X-Cache-Lookup: MISS from sylviosuse11:3128
> Via: 1.1 sylviosuse11 (squid/3.4.4)
> Connection: keep-alive
>
Received on Tue Apr 08 2014 - 02:35:16 MDT