I have a Linux server and I would like a PHP script to monitor a list of websites to check if they are active. For example I would like to check for any websites returning a 500 internal server error. Upon detecting this error I would like an email and SMS notification sent.
I understand the script needs to be called either by a CRON job or internal scheduler on a regular basis such as every 5 minutes.
I wish to reiterate that the websites being monitored are hosted externally on a Windows server but a Linux server will be used to do the monitoring.