CPUOverloadCheck

CPUOverloadCheck

Description

A RouterOS script that periodically measures CPU load multiple times, calculates the average load, and sends an email notification if the average CPU usage exceeds a predefined threshold.

The script includes built-in protection against concurrent executions by using a scheduler with a check for already running instances.

Requirements

• RouterOS with configured mail sending (SMTP).
• Availability of auxiliary script SendEmailFunction for sending emails.
• Script access policies: read, write, policy, test.
• Make sure your SMTP server allows sending emails from MikroTik.

Installing the script

1. Import the main script

/import file-name=Script_CPUOverloadCheck.rsc

or copy the script contents into a new script via Winbox/WebFig.

2. Edit the script configuration

Replace the recipient email address in the script

:local SendTo "YOUR_NAME@DOMAIN.com" with your real email address.

Adjust the CPU load threshold (DeviceAverageLoadThreshold) and number of measurements (NumberOfMeasurements) if needed.

3. Import the scheduler script

Import the schedule from Schedule_CPUOverloadCheck.rsc or create the scheduler manually as below.

Scheduler setup

The scheduler runs the CPUOverloadCheck script every 5 minutes and prevents concurrent runs:

/system scheduler add name=CPUOverloadCheck interval=5m on-event=":local ScriptName \"CPUOverloadCheck\"; :local ScriptRunning [system script job find where script=\$ScriptName]; :if (\$ScriptRunning) do={ :log info \"The script \$ScriptName cannot be run, it is already running (consider increasing interval or reducing measurements)\"; } else={ /system script run \$ScriptName; }" comment="CPU overload check with concurrency protection" policy=read,write,policy,test start-time=startup

Sample email subject and message

Subject: Mikrotik CPU Average Overload: MyRouterName - 75% [01/07/2025 14:35:22]

CPU AR9344 utilization exceeded 70% threshold. Result of 5 CPU load measurements: 68% 72% 78% 76% 84%

Testing the work

Run the script manually in the terminal:

/system script run CPUOverloadCheck

Check logs for script events and notifications:

/log print where message~"CPUOverloadCheck"

Security

• Limit access to the script and scheduler by assigning proper user rights and policies.
• Use a dedicated and secure mailbox for receiving notifications.

Support

If you have questions, suggestions or bugs, create an issue in the repository: GitHub Profile

Author: Hackitect7

Date: 2025