I have setup squid as a reverse proxy to cache all images off our
servers. Why is it still checking the origin server to see if the
images have been modified? These requests which all yield 304 only
serve to increase load on origin servers. Is there a setting other
than what I have below that will instruct squid to NOT check the origin
servers for 1 day minimum or at least to honor the cache-control? I
setup the refresh pattern as this:

refresh_pattern ^ftp: 1440 20% 10080
refresh_pattern ^gopher: 1440 0% 1440
refresh_pattern ^http: 1440 95% 2880
refresh_pattern . 1440 95% 2880

I checked the headers on the images in question and the cache-control
is set properly below as you can see in teh headers.

> Get Request:
> ---------------
> P3P: CP="ALL DSP COR LAW CUR TAIi IVDi PUBi IND PRE"
> Date: Mon, 07 Nov 2005 01:10:17 GMT
> ETag: "8e92551411e3c51:141c"
> Server: Microsoft-IIS/5.0
> Expires: Tue, 08 Nov 2005 01:10:17 GMT
> X-Powered-By: ASP.NET
> Content-Type: image/jpeg
> Cache-Control: max-age=86400
> Accept-Ranges: bytes
> Last-Modified: Sun, 06 Nov 2005 20:31:34 GMT
> Content-Length: 1604