I use Pandora FMS tool to monitoring my web.
Pandora FMS WEB monitoring is a transactional or synthetic test that truly reproduces the complete browsing "process". It could include features such as authenticating a form, doing click in a menu option, filling in a form and verifying that each process returns a specific text string. Any mistake during the process will have a checking failure as a result. The complete transaction includes the download of all the resources (graphs, animations, etc), that the real browsing has.
WEB monitoring returns a "real" user experience and reporting time of transaction. It is also able to "check" if the complete transaction is finished by checking text output response.http://pandorafms.com