Setup Watchdog Service Monitoring in Plesk

The Watchdog component is a solution that ensures that your server is clean from malware, all services are up and running and there is enough free disk space on the server.
Watchdog can start, stop, and restart the services it monitors, and it can be configured to take actions depending on the stability of a service over some time period.
It can run other utilities and notify you when disk space usage has reached the specified amount.
For the purpose of monitoring services and disk space usage, Watchdog uses the monit utility.
For the purpose of scanning the server for malware, Watchdog uses the Rootkit Hunter utility.
For more information please follow below mention Plesk KB article.
https://docs.plesk.com/en-US/onyx/administrator-guide/server-administration/watchdog-system-monitoring-component.70443/

Configuring Watchdog Settings

In order to configure Watchdog settings follow below mentioned steps-
Go to Extensions > Select Watchdog.
Specify the following settings:

• Automatically refresh pages.
• Monitor all services started by administrator.
• Polling interval.
• Store resource usage statistics.
• Repeat security scan.
• Send reports
• Send e-mail to. (Note all notification will be send to the email id which you will add in this Text Box)
• Sender’s e-mail address.
• SMTP server for sending alerts.

Click Apply to submit the settings.

Monitoring System Services
All services controlled by Plesk will be listed on the Services tab.
Specify the services that should be monitored and specify monitoring preferences:
Click a service name.
Select the Monitor the service checkbox to set the Watchdog to monitor the service Click on OK to save.

Monitoring Disk Usage

For configure and start monitoring disk space usage:
Go to Extensions > Watchdog > the Disks tab.
All connected (mounted) devices will be listed , click on search button.

Then it will provide you total disk installed on your system then click on disk name.
Provide the Disk space usage threshold, and files number threshold and then click OK to set the disk monitoring.

Scanning Server for Malware

To set up and start regular security scanning:
Go to Extensions > Watchdog > the Preferences tab, then specify how often Watchdog should scan the server for malicious code in the Repeat security scan menu and  Click Apply.

View Scanning Report

To view the report for the last system scan:

Go to Extensions > Watchdog > the Security tab.
The detailed report will be presented on the screen. If you wish to run a new scan, click the Refresh icon in the Tools group.

Viewing CPU and RAM Usage Statistics