Re: [squid-users] Squid returns old Expires: header

> Thanks for your assistance. I'm using 2.6.STABLE4, btw. I've been
> aware reload-into-ims violates HTTP (and love using it nonetheless),
> but I hadn't anticipated this behavior to be a side effect
> of reload-into-ims.

It's a side-effect of bug #7 which is made noticable by reload-into-ims.

> I will follow your advice. however...
>
>> - upgrade to the latest squid release to get the latest fix for this
>> - bypass the reload-to-ims for these images
>> - purge the current items from your cache.
>
> if your first suggestion is a fix, why do I need to do the other two?
> (Is there some way I can continue to use reload-into-ims? I suppose I
> could always go the route of having Apache strip off no-cache
> headers.)

The bug is not fully solved yet, but there is a partial fix in recent
releases.

After the upgrade you will need to check for the problem again and see if
the partial fix was enough. You might get away with it if the items are
requested frequently enough. Or you may still need to selectively do the
bypass on some critical items.

Amos

>
> Thanks again,
> Ed
>
> On Tue, Mar 25, 2008 at 5:28 PM, Amos Jeffries <squid3@treenet.co.nz>
> wrote:
>>
>> Ed Eddington wrote:
>> > I'm having a problem where Squid is returning the cached Expires:
>> > header with a cached image. (These images are specified in CSS, so
>> > mouse roll-over is causing lots of re-requests for the images by the
>> > browser!) I have reload-into-ims turned on, so a browser reload turns
>> > into an If-Modified-Since request, which works as expected. The IMS
>> > response indicates 304 Not Modified and includes a new Expires:
>> header
>> > in the future (and also includes a Last-Modified: header). However,
>> > Squid never updates the cached image with the newer Expires:
>> date/time
>> > and always returns the one from the cached object (which is now
>> months
>> > old). Any suggestions how I can get Squid to update the cached copy
>> > and return the newer Expires: date/time? Here's my refresh pattern:
>> >
>> > refresh_pattern . 60 0% 60 reload-into-ims
>> >
>>
>> Well, you fail to mention your version of squid. But this is an old
>> problem with workarounds.
>>
>> If you encounter problems with proxies configured to violate HTTP.
>> Expect to be told to unconfigure the violation.
>>
>> So:
>> - upgrade to the latest squid release to get the latest fix for this
>> - bypass the reload-to-ims for these images
>> - purge the current items from your cache.
>>
>> Amos
>> --
>> Please use Squid 2.6STABLE17+ or 3.0STABLE1+
>> There are serious security advisories out on all earlier releases.
>>
>>
>
Received on Tue Mar 25 2008 - 20:38:07 MDT