July 5, 2021

How to Test Mainframe LPARs

Open Source Automation

What are mainframe LPARs? And how do you test them? Find out in this blog!

Table of Contents:

What Are Mainframe LPARs?

LPARs (logical partitions) are a virtualized separate machine that are a subset of the computer’s hardware, such as the mainframe. Also known as Virtual Machines (VMs), mainframe LPARs act like separate mainframes and require performance and functional testing to ensure quality. This blog post will explain how to test mainframe LPARs with BlazeMeter and the JMeter RTE plugin.

How to Test Mainframe LPARs

Step 1: Create a JMeter RTE Script

1. Create a new JMeter test plan

2. Select File -> Template, and the “Recording RTE” template.

3. Define the bzm – RTE Config step

4. Enter the MF LPAR name. It is recommended that you use the FQN  (fully qualified name).

5. Add the port assigned to the mainframe LPAR. For MF LPAR, the default port is usually a secured port.

6. Select the protocol “TN3270”.

7. Select the terminal type “IBM-3278-M5: 27x132”. This is the recommended terminal type to use.

8. Choose the SSL Type. This will depend on the type of certificate that has been defined to the secured connection. It could be SSLv3 or TLS.

Display of SSL types

9. Provide the mainframe username and password during the recording session. It is recommended that you either capture the “Transfer: Yes” label or setup a different label afterwards to make sure that the process worked correctly.

Screenshot of mainframe options

Now, set up a series of assertions for verification purposes. 

10. We start this process by creating a “bzm - RTE Sampler”, and we recommend that you rename it as shown below.

Setting up series of assertions
  • Change the name to “bzm-RTE enter dataset to look up”
  • The action to be selected is “Send Keys” (which are the keystrokes that are being sent out to the mainframe LPAR).
  • The payload will have the following entries (add according to your test):
    • Field = Tabulator
    • Repeat = 5
    • Value = “public.bzm.*”

11. Now we are going to create a response assertion as shown below.

Creating response assertion

Enter the following values

  • Name = “Check file existence”
  • Apply = “Main sample and sub-samples”
  • Pattern Matching Rules = “Substring”
  • Pattern to Test = “PUBLIC.BZM.TEST1”

It is recommended that the captured steps be renamed for easier follow through. This is useful when running the script again.

Renaming captures steps

The results tree will show you each of the steps as they were executed. The assertion will also provide the user with the verification that the dataset that we are checking for does exist, which makeד the assertion valid.

Result tree showing executed steps

Now that the JMeter script based on the RTE recording template has been tested and all the steps have been successfully completed,, we will use this newly created JMeter test and create a BlazeMeter functional test. This will enable you to automate your test.

Step 2: Create Your Blazemeter API Functional Test for Mainframe LPARs

Before we dive into the BlazeMeter script, let’s look at the architecture of such a test.

The BlazeMeter RTE Architecture 

The architecture utilized for a successful interaction between BlazeMeter and the mainframe LPARs residing behind a corporate firewall is shown below:

Diagram of interaction behind firewall

Typical Blazemeter OPL deployment to access MF LPARS

The Blazemeter On-premise Private Location (OPL) is the key component that needs to be deployed prior to the API functional test.

Building the BlazeMeter Test

1. Click on “Functional” in the top nav bar, and then on “API Functional Test”.

Blazemeter testing types

2. Rename the test with the appropriate name.

3.  Select the three vertical dots at the bottom, as shown below, and then “Upload existing test script (e.g. JMeter)” to load the newly created JMeter script from before.

Uploading testing form

4. Once the JMeter script has been uploaded and validated, make sure that the correct OPL is selected as shown below.

Select correct OPL

5. Once all of these steps have been completed, execute the test and you will see the test running.

Executed test is running

6. View and monitor the results.

View the results

As we browse the different steps of the test, you will be able to see the different mainframe actions as they were executed.

You can also see the results of each of the executed steps. The information is shown in the response section of the “bzm-RTE-second login message” that is displayed below.

Execution information shown

That’s it! You now know how to create a JMeter script using the RTE recording template and how to use it to test mainframe LPARs that are behind corporate firewalls via the Blazemeter API functional tests. 


Related Resources: