Is there any program that can be installed on CentOS and notify a via email when a webserver/site/webservices drops and does not respond anymore?
I was trying to use Cacti, but as I have been answered here, Cacti is used for graphs
Other than writing your own cron script, I'm not sure about it running on your own CentOS server. I use pingdom myself though. https://www.pingdom.com/
Try this solution that uses the built-in utility cron. As written, this script will detect a failed service and restart it. But it won't detect a running, non-responsive service. For that case, you could add a few lines that use curl to test a website URL for HTTP response code, and then you could restart the service if you get anything that is 4xx or 5xx. https://stackoverflow.com/a/9072923/5759901
