Re: [squid-users] Zero hit rate on reverse proxy server with Squid

tis 2006-05-16 klockan 18:19 -0700 skrev Michael T. Halligan:

> > a) Authentication was used, and the server did not indicate the
> > content
> > is public (not requiring authentication).
>
>
> Is there something special that I need to do in apache to make it
> say that the data is "public" once
> it's been authenticated?

Data requiring authentication is per definition not public, it's limited
access.

Data which can be considered public (unlimited access) even if the
server normally requires authentication can be marked as such by
including a "Cache-Control: public" header in the HTTP response. This
tells caches that the content is considered "unlimited access" even if
the request which gave this content included authentication credentials.

> > b) Reload request (max-age=0)
> >
> > c) If-Modified-Since can only be cached once the object as such has
> > been
> > cached.
>
> I'm rather squid illiterate here. Where do I begin to research these
> two statements?

b) Don't use the reload button when testing the cache. The reload button
tells caches that the client wants a fresh copy by including the above
mentioned criteria in it's request..

c) Start with a clean browser cache when testing. Squid can only cache
content which has been seen by Squid. Positive cache validations of
content not yet seen by Squid is not cached.

A good document explaining how HTTP caching works and how to make proper
use of it is "Caching Tutorial for Web Authors and Webmasters"
<url:http://www.mnot.net/cache_docs/>. It not only explains the concepts
involved but also how this maps to several common HTTP servers and
related technologies.

Regards
Henrik