Have you ever been having a good weekend, and you come into work Monday and *boom* — there was a power outage over the weekend. Some services on your servers started, others didn’t. Wouldn’t it be nice to be notified that services aren’t working, and even better if they were automatically fixed??
Enter Monit. Their website describes it best:
Monit can start a process if it does not run, restart a process if it does not respond and stop a process if it uses too much resources. You can use monit to monitor files, directories and devices for changes, such as timestamp changes, checksum changes or size changes. You can also monitor remote hosts; monit can ping a remote host and can check TCP/IP port connections and server protocols. Monit is controlled via an easy to use control file based on a free-format, token-oriented syntax. Monit logs to syslog or to its own log file and notifies you about error conditions and recovery status via customizable alert.