JMeter: Distributed (Remote) Testing
JMeter is popular open source load testing
software from Apache and it is a Java Graphical application. The easiest way to
run it in Amazon EC2 is in a windows server so it could be easily access via
RDP.JMeter has a master/slave architecture where the client is the master and multiple JMeter servers are slaves running tests in a scalable fashion. I tried to set up an environment where the master instance would be hosted by my workstation behind corporate firewall but due to the corporate polices with regards to setting up inbound rules in the firewall it proved to be a challenge.
So, I gave up and went with the approach where I set up both the master and client(s) in Amazon EC2, the master on a large instance so it has the CPU to process the graphs and the slave(s) on medium instances that have the network capacity to run the tests.
In order to be able to set up distributed environment you have to have some basic knowledge of how to spin up and Amazon server image and set up security groups (and the concept of AWS security groups). You have to be logged into AWS console in order to accomplish it.
Terminology
Before we dive into the
step-by-step instructions, it's a good idea to define the terms and make sure
the definition is clear.
Master– the system
running Jmeter GUI, which controls the test
Slave– the system
running jmeter-server, which takes commands from the GUI and send requests to
the target system(s)
Target– the webserver to
stress test
Important notes
Make sure that all the nodes (client and servers) :
- are running exactly the same version of JMeter.
- are using the same version of Java on all systems.
Using different versions of Java may work but is discouraged. I had to
download in install the same version of JDK across all servers that I used
in the test.
Step-by-step guide
- Log in AWS console.
- Define two security groups, one to be used by the master and another one by the slave. Go with default values, you will tailor them later once you have spun up the server images.
- Pick an Amazon Windows Image. In my case I selected 64 bit Windows 2008 R2 Server image (the same was selected for the second image). Launch a large instance (for the master). Take note of its public IP addresses. In my case I had '54.86.105.11'. Make sure that port 3389 (security group) open for RDP, the same would apply for the second image (see below)
- Launch a medium instance to be used as a host for a slave. In a case when a few slaves are required then more instances should be launched. Take note of their public IP addresses. I spun a single instance with the following IP address: '54.166.224.129'
- Edit the (master) security group with the following inbound rule (see the screenshot below). The IP address of the slave's host should be used with the CIDR notation, that is the /32 prefix should be appended to the IP address. Note, I picked an arbitrary port 51000. Could be any port as long as it is not in use by any other process. Once you have edited it, the changes will be applied on the fly to the created image.
- This port would be used to transfer test results from the slave server over to the master.
- Edit the (slave) security group with the following inbound rule (see the screenshot below). The IP address of the slave's host should be used with the CIDR notation, that is the '/32' prefix should be added to the IP address. Note, I picked an arbitrary port 4000. Could be any port as long as it is not in use by any other process.
- This port will be used for the master server to pass a set of test instructions to the slave machine. The master will be listening to this one port only to receive results. That means that all of the slaves will be sending their results back through this port.
- Now, navigate to the slave host and into the [JMETER_HOME]/bin directory. Open jmeter.properties file and make sure to edit the following properties in the Remote hosts and RMI configuraion section of this file:
- Now, on the slave host in the same [JMETER_HOME]/bin directory launch the JMeter application via command line, making sure to pass the public IP address of the slave's host. YOu are going to end up with the following output:
- On the master machine similar to step one edit a few properties as indicated below in the jmeter.properties file
- On the master machine launch JMeter GUI and select the slave's host in the shortcut menu which should get the test going:
