Re: Problem with object which should not be cached

From: Henrik Nordstrom <hno@dont-contact.us>
Date: Thu, 13 May 1999 08:00:20 +0200

David Luyer wrote:

> They have managed to get their Netscape Enterprise server 3.5.1C to insert
> cache-control: no-cache headers. However,
>
> * if the object is requested via HTTP/1.0 from nillu.nla.gov.au, no cache control
> header is sent

> * regardless of whether I send an HTTP/1.0 or HTTP/1.1 request to Squid, it
> is sending an HTTP/1.0 request to nillu.nla.gov.au

Squid is a HTTP/1.0 proxy. Only minimal support for selected headers
from HTTP/1.1 is available. Changing Squid to claim that it is a
HTTP/1.1 agent would defenitely cause more problem than it solves.

> I'm not sure exactly where to go from here. One problem is that the response to
> the HTTP/1.0 request shows no indication the object shouldn't be cached,
> another problem is that squid is choosing to use HTTP/1.0 for this server.

The correct method for making a HTTP/1.0 reply uncachable is to set the
Expires header to the current date..

Unofficial method is to set "Pragma: no-cache".

A perhaps better approach would be to replace the left panel with
another object after login. I.e. separate the GUI into "not logged in"
and "logged in" pages.

And as usual, do not have a Squid refresh_pattern with a min age other
than 0 unless you know what you are dealing with. Doing so will break
many dynamic applications.

--
Henrik Nordstrom
Spare time Squid hacker
Received on Tue Jul 29 2003 - 13:15:58 MDT

This archive was generated by hypermail pre-2.1.9 : Tue Dec 09 2003 - 16:12:08 MST