I am trying to get mod disk_cache to permantly cache images retrieved from an image server on the webserver using ProxyPass.

While the image is being retrieved correctly from the server and is served from the cache on further requests, then I am still having the webserver call the image server and causing the cached header to be updated. Because of load concerns then I need to never call the image server on a specific url again after it has been cached once, or extend the refresh time for as long as possible.

The webserver is IHS 7.0 The mod's are mod_disk_cache.so, mod_cache.so, mod_proxy.so Version 2.2.8.0

Following is from my httpd.conf:

ProxyPass       /webserver/media/images/  http://imageserver.com/ws/media/images/

# Caching  pictures
<IfModule mod_cache.c>
    <IfModule mod_disk_cache.c>
        CacheDefaultExpire 2628000 
        #CacheDisable
        CacheEnable disk /webserver/media/images/
        CacheIgnoreCacheControl On 
        CacheIgnoreHeaders Cookie Referer User-Agent X-Forwarded-For X-Forwarded-Host X-Forwarded-Server Accept-Language Accept Host
        CacheIgnoreNoLastMod On 
        CacheIgnoreQueryString Off 
        #CacheIgnoreURLSessionIdentifiers 
        CacheLastModifiedFactor 10000000.1 
        #CacheLock on 
        #CacheLockMaxAge 5 
        #CacheLockPath
        CacheMaxExpire 1576800 
        CacheStoreNoStore On 
        CacheStorePrivate On 

        CacheDirLength 2 
        CacheDirLevels 3 
        CacheMaxFileSize 1000000 
        CacheMinFileSize 1 
        CacheRoot c:/cacheroot2 
    </IfModule> 
</IfModule>