phpWatch is a Free site uptime monitoring PHP Script. You can setup this tool to watch unlimited websites and it also gives the options to send notifications via email / sms (for US only).
The purpose of this system is two-fold: it allows administrators to easily check the status of many different services running on any number of servers and also allows developers to interface with the query and notification APIs.
The AJAX based user-interface makes it simple to view, add, edit, and delete service monitors as well as notifications on a single page. The configuration page allows users to customize and format the notifications that are sent out during a service outage.
Requirements: PHP, MySQL
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