CERN HTTPD 3.0 can be configured to perform as a caching proxy server (see section 5.4). This is important, because it can greatly improve external performance for your local users and also greatly reduce international traffic.
Caching can be enabled by commands in the main server configuration file. The following is a typical configuration setup:
CacheSize 300 M
The first few lines here configure the server as a proxy server. In this case we have configured the server to be a proxy server for http, gopher and ftp using the `` Pass'' commands. We've also configured it to use an outer proxy server at www.hensa.ac.uk for sites that are not in the UK.
The next few lines configure the way the cache behaves. `` CacheSize'' configures the maximum amount of space the server is to use for its cache - in the case 300 MBytes. `` CacheRoot'' specifies the directory to store the cache temporary files in. Note that if your system manager backs up your filestore periodically, these cache files should not be backed up, or they will add unnnecessary load on your backup system.
The last two lines take a little more explanation:
A number of other cache control commands are also available for use in the server configuration file, and are described in more detail in the CERN HTTPD Reference Manual.