Using web server logs to ensure browser caching is working

The first time a browser requests a file, an HTTP code of 200 (request for document) will be written to the web server log. It will look like this:
30.35.127.106 – – [21/Oct/2006:14:38:23 -0700] “GET /OA_MEDIA/FNDREDPT.gif HTTP/1.1” 200 70

The next time the request is received from the browser, it should be served by the browser cache. Thus the entry in the web server log file will be an HTTP code 304 (request for time stamp). It will look like this:

130.35.127.106 – – [21/Oct/2006:14:41:03 -0700] “GET /OA_MEDIA/appslogo.gif HTTP/1.1” 304