Monit
Monit is a small Open Source utility for managing and monitoring Unix systems. Monit conducts automatic maintenance and repair and can execute meaningful causal actions in error situations.
Monit has the ability to start a process if it is not running, restart a process if not responding, and stop a process if uses high resources. Additionally, you can also use Monit to monitor files, directories, and filesystems for changes, checksum changes, file size changes, or timestamp changes.
With Monit, you can able to monitor remote hosts’ TCP/IP port, server protocols, and ping. Monit keeps its own log file and alerts about any critical error conditions and recovery status.
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