Prerequisites For Mainframe Testing

Below are some of the prerequisites of mainframe testing:

• A login ID and password are required to access the application.
• A basic understanding of ISPF commands.
• The file names, file qualifiers, and kinds are all listed.

The following points should be checked before beginning mainframe testing.

1. Job:

• Before performing a job, do a job scan (Command – JOBSCAN) to check for problems.
• The test class should be specified in the CLASS parameter.
• By utilizing the MSGCLASS argument, one can direct the task output to a spool, a JHS, or wherever else one wants.
• Redirect the job’s email to a spool or a test mail ID.
• For initial testing, comment out the FTP steps and point the job to a test server.
• If the job generates an IMR (Incident Management Record), just comment “TESTING PURPOSE” on the job or param card.
• All of the job’s production libraries should be switched to test libraries.
• It is not a good idea to leave the job unattended.
• TIME parameter should be added with a specified time to avoid the job from running in an infinite loop if there is an error.
• Save the job’s output, which includes the spool. XDC can be used to save the spool.

2. File:

• Only make a test file of the required size. When storing data into successive files with the same name, use GDGs (Generation Data Groups – Files with the same name but sequential version numbers– MYLIB.LIB.TEST.G0001V00, MYLIB.LIB.TEST.G0002V00, and so on).
• The files’ DISP (Disposition – defines the procedure for keeping or deleting the dataset following a normal or abnormal step or task termination) parameter should be coded correctly.
• To avoid the job going into HOLD, make sure all of the files utilized for job execution are saved and closed appropriately.
• If you’re using GDGs to test, make sure you’re pointing at the correct version.

3. Database:

• Ensure that no undesired data is inserted, changed, or deleted while running the job or online program.
• Also, make sure you’re testing in the correct DB2 region.

4. Test Case:

• Always check for boundary conditions such as an empty file, the first record being processed, the last record being processed, and so on.
• Include both positive and negative test conditions whenever possible.
• Include test cases to validate if the modules have been utilized correctly if standard procedures are used in the software, such as Checkpoint restart, Abend Modules, Control files, and so on.

5. Test Data:

• Before you start testing, make sure the test data is ready.
• Never make changes to the test region’s data without first informing the user. Other teams may be working with the same data, and their tests may fail.
• Before copying or accessing the production files, sufficient authorization should be obtained.

Mainframe testing is used to evaluate software, applications, and services built on Mainframe Systems. The major goal of mainframe testing is to ensure the application or service’s dependability, performance, and excellence through verification and validation methodologies, and to determine if it is ready to launch or not. Because CICS screens are custom-built for specific applications, the tester just has to know how to navigate them when performing Mainframe testing. Also, if the code in COBOL, JCL, or other languages is changed, the tester does not have to worry about the emulator being set up on the system.

Here, we will discuss the following points:

1. What is Mainframe?
2. Mainframe Testing Methodologies.
3. Prerequisites for Mainframe Testing.
4. Mainframe Attributes.
5. Steps for Mainframe Testing.
6. Mainframe Testing Procedures To Follow.
7. Types of Mainframe Manual Testing. 
8. Mainframe Automation Testing Tools.
9. Best Practices For Mainframe Testing.
10. Mainframe Testing Challenges and Troubleshooting.
11. Benefits of Mainframe Testing.