Re: [squid-users] force caching (or High availability config)

On Dec 13, 2007, at 3:57 PM, Dmitry S. Makovey wrote:

>
> Hi,
>
> I have squid configured as a transparent proxy in front of
> application server
> (ApS). Data generated by ApS gets updated infrequently and sometimes
> ApS gets
> slow doing it's internal "housecleaning". What I want to do is for
> Squid
> to "fudge" response times a bit by timing out connections to ApS
> after, say
> 20s and using cached data instead (even if it's outdated). This
> would also
> help with ApS reboots so that data is available at all times
> regardless of
> responsiveness or availability of ApS.
>
> Looking through documentation and Google searches didn't bring up
> any relevant
> information.
>
> I do realize that this violates HTTP and is not widely applicable
> but in my
> situation I can live with consequences (I think).

This is actually a feature we've been interested in as well. As far
as I know, there's no way to do this in Squid right now, though it was
discussed before by one of my co-workers and apparently there was a
similar feature being developed, I don't know if that ever made it
into the mainline code or not, I'm sure one of the developers can
comment.

What we've done instead is leverage offline mode so that if the
application servers get themselves into a state where they wont reply
in a timely manner, the caches are automatically toggled into offline
mode by a watchdog daemon. That might, depending on your
configuration and your ability to monitor your application server's
state, be an option you can consider in lieu of doing it entirely in
Squid.

--Dave
Systems Administrator
Zope Corp.
540-361-1722
david@zope.com
Received on Thu Dec 13 2007 - 14:27:50 MST