Mainframe Interview Experience with XYZ Bank | Jan 2022

BRIEF Yourself?

1. About you, project details, and Roles and responsibilities?

VERSION CONTROL TOOL (CHANGEMAN):

1. Version control tool, which one?
2. What are the steps in promoting a CHGMAN Package?
3. How do you manage a release for March and July having some same components?
4. if someone has done the code changes for a component of July release, how can you manage the same component in March release. How will you do version controlling in that case?
5. How will you generally do version control, if 2-3 people are working on same component?
6. Something went wrong! How would you backout changes, and/or release previous version of components?
7. Entire package will be backed out, or just the impacted components?

JCL:

1. Streamline/unified way of accessing JCL/PROCS at one place?
2. How would you provide override in proc for some files in a step?
3. A release went. One step was missing in PROC in the middle. How would you temp add that step and run the job?
4. A job has many steps (>10), but you need to some steps on various scenarios for testing. Never needs to run all steps. Always some cases and corresponding steps only! How can you automate/streamline/optimize this without everytime making changes to JCL. Best way to optimize this?
5. S806 ABEND FOR?
6. JOBLIB/JCLLIB/STEPLIB difference? How and why to use?

COBOL:

1. COPY vs INCLUDE
2. String at random places in record. How to identify and write only those records to output file.
3. REC1 to 1st file, REC2 to 2nd file, and REC3 to 3rd file,....REC4 to 1st file, and so on....Logic?
4. How would you check for NUMERIC if the datatype is ALPHANUMERIC (ex: FHSFAHF3612436, or, 667888778)?
5. Copybook changes impact analysis?
6. How will you make sure you are not missing any component for Copybook change impact?

Db2:

1. Can we do Db2 bind in production? If yes, then how?
2. Is changing of Isolation level directly in production possible? How will you do that?
3. Select those employees from a table who logged in last 10 minutes?

CICS:

1. VSAM accessed by a CICS program got corrupted. How would to correct it in run time?
2. CEDA command?
3. Define COBOL-CICS process? How to test that program?
4. {NEWCOPY}

VSAM:

1. How can you check whether a file is a VSAM file? What are different ways, if you know?
2. How can you check whether a VSAM file FB, F, VB etc?
3. How to define alternate index on a VSAM? State all steps?
4. What will you do extra in a JCL if a VSAM file defined with Alternate index? State both 1) when accessing alternate indexes in JCL alone 2) when accessing alternate index in COBOL program?
5. Can alternate index have duplicate? Is there a Limit to it, like how many dups it can have?

FILE TRANSFER WAYS (FOR MAINFRAMES):

1. MQ - What would you do extra to setup this pipeline? like XML, queue manager etc. 33.SFTP
2. RESTful
3. CICS Webservices
4. OMVS/Unix flavour

BONUS QUESTIONS:

1. A file is getting read by a COBOL program. The records in the file having a KEY(Length=5) at random position but always preceeded(lead) by a '/' (example: ruefuwr/12345egfuewguf). Your task is to Sort the file based on this KEY value and write the records to an output file without changing anything, expect sorting. How would you do that?

Thank You!
MOHIT WADHWA