Re: [squid-users] squid and php-sites

This pattern will not cache such replies as they are fresh for 0 seconds
and cannot be revalidated, meaning that even if Squid did cache these it
would never be able to reuse the cached content as it is immediately
stale and without any validators it cannot ask the origin server if the
same reply is still up to date on a later request.

To have such replies cached you need to use a refresh pattern with min >
60 seconds, telling Squid that even if the reply did not have any
information regarding to fresshess or expiration time it is OK to cache
it for the min age in your refresh pattern.

Note: Doing so WILL BREAK certain web sites with dynamic content not
aware of the existence of shared web caches like Squid, possibly leaking
private information between different users. In all such cases the error
is at the origin web server not telling that the information is private,
but it is extremely likely your cache will be blaimed as it works
without caches or with most other caches not having such refresh pattern
rule.

Regards
Henrik

alp wrote:
>
> hi henrik,
>
> 1) refresh_pattern . 0 20% 4320
> if i understand your note correctly, this is not correct for php-sites???
> but it should, since the dot finds any object, doesn't it?
> nevertheless, i also tried
> refresh_pattern \.php 0 20% 4320
> with the same effect (see 2)
>
> 2)
> if i do the request for test.php i see:
> HTTP/1.0 200 OK
> Daten: Sat, 15 Feb 2003 08:00:00 GMT
> Server: Apache/1.3.27 PHP/4.1.2
> X-Powered-By: PHP/4.1.2
> Content-Type: text/html
> X-Cache: MISS from test.de
> Connection: close
>
> hi-php
>
> (the last line is the content of the file)
> and still it is not in the cache
>
> does this help in finding an explanation?
>
> ----- Original Message -----
> From: "Henrik Nordstrom" <hno@squid-cache.org>
> To: "alp" <alpheus@gmx.de>
> Cc: <squid-users@squid-cache.org>
> Sent: Friday, February 14, 2003 8:04 PM
> Subject: Re: [squid-users] squid and php-sites
>
> > Two questions:
> >
> > 1. What is your refresh_pattern settings?
> >
> > 2. What is the full headers returend by your server?
> >
> > Just tested this with Squid-2.5 and a reply with only a Date header and
> > some content is cached if your refresh_pattern says it should be.
> >
> >
> > Note: The default refresh_pattern settings does not cache such replies
> > for the reasons indicated before.
> >
> > Regards
> > Henrik
> >
> >
> > alp wrote:
> > >
> > > sorry, i misunderstood your first reply.
> > > BUT:
> > > i have a site test.php (without any php-code, just for testing the
> suffix)
> > > on an apache server.
> > > it sends this site only with the DATE-header. no lastmod, no expires. it
> > > also does not mark the object as not cacheable.
> > > so the refresh-pattern IS used, as you say.
> > >
> > > so, first call:
> > > echo -e "GET /test.php HTTP/1.0\nHost:myhost\n\n" | netcat squidserver
> 80
> > > gives the file together with the above header (date)
> > > second call:
> > > echo -e "GET /test.php
> > > HTTP/1.0\nHost:myhost\ncache-control:only-if-cached\n\n" | netcat
> > > squidserver 80
> > > it says: object is not in cache.
> > >
> > > ???
> > > doing the same with a file test.html i see the lastmod header and it is
> of
> > > course cached.
> > >
> > > i still seem to miss some important point in understanding this, i
> guess.
> > > but for me it seems as if the refresh-pattern is not used.
> >
Received on Sat Feb 15 2003 - 04:52:35 MST