Uptime is a comprehensive website uptime monitoring service which you can use to monitor any number of websites around the world.
If one of your sites goes down you can check it manually on the Uptime site or get alerted by email so you can check your “downed” site out.
Some features of Uptime include:
Beautiful and simple interface
Unlimited number of websites/individual pages can be monitored
AJAX Powered “Check Now” function
Ability to set up scheduled CRON job with email alerts
In depth documentation
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