RE: page updates

> From: Jorg B. [SMTP:jorg_b@cwo.com]
>
> I have noticed a few times that when somebody telnets to a remote server
> to
> make some changes to his/her site that squid does not "see" the changes
> being made. What triggers squid to "get" the new page instead of using the
>
> cached one ?
>
        See the HTTP specification and the description of, in
        particular, refresh-patterns, in squid.conf. Basically,
        if the page has explicitly expired, or the heuristics for
        estimating expiry of pages indicate it has expired, squid
        will do a conditional GET. The heuristics rely on there
        being a modified date available.

> Does "shift reload" force squid to pull a new copy of the page from the
> remote server ?
>
        Depends on the client. Netscape shift reload adds
        HTTP headers which prevent the use of a cache. There are
        at least three distinct cases that can be generated at the
        HTTP level:

        - check with immediate parent that the page is current;

        - end to end check that it is current;

        - force end to end reload.

        I don't think Netscape gives access to all of these options,
        and IE uses control reload for the second/third one (not sure
        which, and have never seen it documented, so treat as
        apocryphal).
Received on Thu Jul 29 1999 - 05:33:46 MDT