Q. How do I install monit to monitor my server under Debian / Ubuntu Linux?

A. monit is a utility for managing and monitoring processes, files, directories and devices on a Debian / Ubuntu Linux server system. Common monit usage:
a) Monit can start a process if it does not run
b) Restart a process if it does not respond
c) Stop a process if it uses to much resources etc

How do I install monit utility for monitoring services?

Simply type the following command as the root user:
$ sudo apt-get update
$ sudo apt-get install monit


Configure monit

Open monit configuration file /etc/monit/monitrc using vi text editor:
# vi /etc/monit/monitrc
You need to set following parameters:
set daemon 120
set logfile syslog facility log_daemon
set mailserver localhost # primary mailserver
set alert vivek@nixcraft.com # receive all alerts

Save and close the file. Where,

• set daemon 120 : Start monit in background as daemon and check the services at 2-minute intervals.
• set logfile syslog facility log_daemon : Log messages in /var/log/messsages file
• set mailserver localhost : Send email alert via localmail server such as sendmail. Set list of mailservers for alert delivery. Multiple servers may be specified using comma separator. By default monit uses port 25 – it is possible to override it with the PORT option.
• set alert vivek@nixcraft.com : You can set the alert recipients here, which will receive the alert for each service. The event alerts may be restricted using the list.

Now open /etc/default/monit file to turn on monit service:
# vi /etc/default/monit
Set startup to 1, so monit can start:
startup=1
Save and close the file. Start the monit Linux monitor tool / service:
# /etc/init.d/monit start