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Practical step by step guide for setting up distributed JMeter

Its well known that JMeter can run in a distributed environment. This means that the complete environment has one controller (called master by JMeter) and multiple runners (which are called slaves by JMeter). I prefer to use the words controller over master and runner over slave. Even JMeter is an old tool it was difficult for me to set it up, because a simple guide for setting up was missing and the terms used by JMeter were misleading for me.

Let’s hope that this step-by-step-guide may help you to set up your distributed JMeter-environment from scratch.

Requirements

You need

  • JMeter - when I wrote this article it was 5.8
  • One computer which acts as a controller
  • (at least) one computer which acts as a runner. It is possible to run the runner on the controller computer. If this is the only runner you are using than it might be simpler to run your JMeter tests non-distributed.
  • one computer which acts as a system under test
  • a JMeter test which has already been written

Overview

Jmeter uses RMI (Java Remote Interface) for communicating between controller and runners. If you wish to utilize your setup in a firewall-protected environment, it’s essential to explicitly configure the ports which JMeter should use. This step is crucial for configuring your firewall correctly. Normally the communication happens encrypted. But JMeter has a bug which does prevents you to define ports in controller and using encryption. You also need the IP-Addresses of each runner

Deploymentoverview Deployment-overview

Setting up controller and runner

Setting up the controller

  • copy the JMeter package to controller and unzip it in a directory e.g. /opt/jmeter/ which is named JMETER_CONTROLLER_HOME in following
  • Go to $JMETER_CONTROLLER_HOME/bin
  • open file jmeter.properties
  • Change the content of the following settings
    • client.rmi.localport to 40010 - You can choose any portnumber you want. If this property is set, JMeter uses it as base-port meaning it opens two ports above for communicating. In the given example it means the ports 400011 and 40012 will be opened. If you have a firewall you need to open the ports 40011 and 40012. If the runners can not open a connection to that port the controller will not receive any progress information of the runners. No progress information also means that the runner can not inform the controller that execution finished.
    • server.rmi.disable to true - This is required because JMeter has a bug. If you keep encryption enabled your controller will not start and you receive a error message. Hopefully in future releases this bug gets fixed.

Setting up the runner

  • copy the JMeter package to runner and unzip it in a directory e.g. /opt/jmeterrunner/ which is named JMETER_RUNER_HOME in following
  • Go to $JMETER_RUNER_HOME/bin
  • open file jmeter.properties
  • Change the following settings
    • server.port to 10000 - You can choose any portnumber you want. If you have a firewall you need to open the port 10001.
    • server.rmi.localport to 10001 - You can choose any portnumber you want. If this setting is set JMeter use it as the port where the runner waits for tasks to be executed. If you have a firewall you need to open the port 10000.
    • server.rmi.disable to true - This is required because JMeter has a bug. Since encryption was disabled in controller we also need to disable it in the runner
  • If you have multiple runners repeat the steps for each runner

Running a distributed test

  • You should have executed everything described under setting up

Starting the runners

  • Login to a runner
  • Go to $JMETER_RUNER_HOME/bin
  • Run jmeter-server
  • The runner is now running and waits for tasks to be executed
  • If you have multiple runners repeat the steps for each runner

Starting the controller

  • Login to controller
  • Go to $JMETER_CONTROLLER_HOME/bin
  • Run jmeter -R <RUNNER_IP_ADDRESS:PORT> -n -t <PATH_TO_JMX_FILE> -l /tmp/execution.log
    • Explanation
      • jmeter- this starts JMeter
      • -R - tells JMeter to run distributed
      • RUNNER_IP_ADDRESS:PORT - a configuration for given example it would be 162.168.2.1:10000
      • -t - do not know
      • -l - writes execution log to that file so you are able to analyze the result of your test
      • Example call with setup of this guide jmeter -R 192.168.1.3:10000,192.168.1.4:10000 -n -t <PATH_TO_JMX_FILE> -l /tmp/execution.log
  • You should see that the controller starts logging to the terminal
  • You should see that the runner receivces some tasks which it executes
  • You should see that something happens on your system under load
  • Depending how large your test is,

Summary

Thanks for following this guide. I hope it works for you. If you have any questions just open an issue in one of my github repositories

References