Mainframe Dev AI Interview Prep

Construct JOB, EXEC, and DD statements with key parameters and diagnose common JCL and dataset errors.

Build reusable procedures (PROCs) with symbolic parameters and manage library overrides (JOBLIB/STEPLIB).

Manage the complete batch file lifecycle using Generation Data Groups (GDGs).

Implement conditional job flow and restart logic using COND, IF/THEN/ELSE, and step RESTART parameters.

Apply DFSORT control cards (SORT, MERGE, OUTFIL, INCLUDE/OMIT) for complex data transformation and reporting.

Use common utility programs (IEBGENER, IEBCOPY, IDCAMS) for essential dataset management tasks.

Solve a scenario: Design a fully restartable multi-step batch stream with checkpointing.

Solve a scenario: Build a single, parameter-driven PROC for deployment across development, testing, and production environments.

Differentiate KSDS, ESDS, RRDS, and LDS organizations and select the appropriate type for a given application requirement.

Define, load, and manage VSAM clusters using IDCAMS commands (DEFINE CLUSTER, REPRO, VERIFY).

Explain the impact of Control Intervals (CI), Control Areas (CA), and free space on performance and storage.

Design, build, and use alternate indexes and PATHs to provide secondary access to a KSDS.

Tune VSAM performance by optimizing buffer allocation (BUFNI/BUFND), CI/CA sizing, and split avoidance strategies.

Recover and reorganize VSAM files using backup/restore procedures and interpret common VSAM return codes.

Diagnose and resolve common VSAM performance issues like CI/CA splits and excessive I/O.

Lead a scenario: Plan and justify a zero-downtime VSAM reorganization strategy for a critical 24x7 file.

Describe the CICS architecture, including regions, tasks, TCBs, and the role of the CWA and EXCI.

Develop CICS screens using EXEC CICS commands for BMS map I/O (SEND MAP, RECEIVE MAP).

Perform CICS file control operations (READ, WRITE, REWRITE, DELETE) on VSAM files with proper exception handling.

Differentiate and apply Temporary Storage (TS) and Transient Data (TD) queues for state management and asynchronous processing.

Ensure data integrity in CICS transactions by implementing Logical Units of Work with SYNCPOINT and SYNCPOINT ROLLBACK.

Design pseudo-conversational CICS programs to efficiently manage state and resources across user interactions.

Diagnose CICS abends (e.g., AEIx, ASRA) using interactive debugging tools like CEDF, CEMT, and CEBR.

Implement threadsafe CICS programs to leverage the Open Transaction Environment (OTE) for improved throughput.

Write REXX scripts using variables, control flow (IF/THEN, DO, SELECT), and the PARSE instruction.

Invoke TSO commands and access sequential and PDS datasets from within a REXX exec.

Automate job and output management by interfacing with the SDSF REXX API.

Create an ISPF panel driven by a REXX exec to build an interactive user tool.

Write a REXX EDIT macro to automate a common, repetitive source code editing task.

Develop a REXX utility to automate parameter-driven JCL generation and submission.

Lead a scenario: Establish a team-wide REXX-based toolkit with standardized coding conventions and shared functions.

Outline the architecture and calculate the ROI for a REXX-driven self-service automation portal for L1 support tasks.

Describe the DB2 for z/OS architecture, including DBM1, IRLM, DDF, and bufferpools.

Write advanced SQL queries using various JOIN types, subqueries, Common Table Expressions (CTEs), and window functions.

Embed SQL in COBOL programs using host variables, DCLGENs, the SQLCA, and cursors for multi-row processing.

Analyze query access paths using EXPLAIN and the PLAN_TABLE to identify performance bottlenecks.

Design and justify appropriate indexes (e.g., clustering, include) for a given set of query patterns.

Apply database concurrency principles, including isolation levels, locking modes, and deadlock-avoidance techniques.

Plan and execute essential database maintenance (RUNSTATS, REORG) and recovery strategies (IMAGE COPY, RECOVER).

Architect a comprehensive VSAM-to-DB2 migration plan, including data mapping, parity testing, and a rollback strategy.

Describe the IMS hierarchical model (segments, DBD, PSB, PCB) and full-function database types (HDAM, HIDAM).

Issue DL/I calls (GU, GN, GNP, ISRT, REPL, DLET) in a COBOL program using both qualified and unqualified SSAs.

Interpret common IMS status codes and implement robust error handling in an IMS batch program.

Design secondary indexes and logical relationships to enable non-hierarchical access paths into an IMS database.

Tune IMS performance through randomizer selection, buffer allocation, and pointer option trade-offs.

Execute IMS database reorganization (HD Unload/Reload) and forward recovery using image copies and logs.

Implement database update backout in a Batch Message Processing (BMP) program and explain the role of DBRC.

Describe CICS-IMS (DBCTL) and IMS-DB2 (ESAF) integration patterns and their sync-point coordination.

Define jobs, folders, and SMART folders with complex scheduling criteria in Control-M.

Configure intricate job dependencies using conditions and quantitative/control resources.

Manage cyclic jobs, advanced calendar definitions, and rule-based calendars for business processing.

Monitor enterprise-wide job flows, troubleshoot failures, and apply appropriate recovery actions (rerun, Force-OK).

Integrate Control-M with distributed systems (Linux/Windows) via agents and file-transfer jobs (AFT).

Integrate Control-M with cloud services (e.g., AWS S3, Azure Blob) using application plugins.

Design a robust recovery and restart strategy for a complex, multi-platform Control-M workflow.

Lead a scenario: Plan a phased migration to Control-M, defining go/no-go criteria, rollback plans, and risk controls.

Compare modernization strategies (rehost, refactor, replatform, rebuild) for legacy COBOL workloads.

Evaluate hybrid mainframe-cloud integration patterns, including API gateways, messaging, and data replication.

Use z/OS Connect to configure and expose a CICS program as a secure REST API.

Use z/OS Connect to configure and expose an IMS transaction as a secure REST API.

Design an OpenAPI (Swagger) specification with request/response mappings for a z/OS backend service.

Secure mainframe APIs using modern standards like OAuth/JWT and TLS.

Define a Change Data Capture (CDC) pipeline to enable real-time data replication from DB2/IMS to a cloud data store.

Describe the components and stages of a modern z/OS DevOps toolchain (Git, Zowe, IDz, CI/CD orchestrator).

Apply core LLM concepts (tokens, context windows) and prompt engineering patterns to mainframe code tasks.

Use an AI assistant to explain and auto-document a complex legacy COBOL paragraph or program.

Apply AI-assisted refactoring to extract a business-logic subroutine from a monolithic COBOL program.

Use watsonx Code Assistant for Z to translate a selected COBOL/DB2 component to a Java service.

Validate AI-generated or refactored code using unit tests, parity testing, and critical human review.

Outline the architecture of a Retrieval-Augmented Generation (RAG) assistant over mainframe technical documentation.

Use AI copilots to accelerate the generation of unit tests for COBOL and DB2 programs.

Apply a prompt engineering pattern to summarize and identify root causes from a sample mainframe log file.

Describe AIOps concepts and identify high-value use cases within a mainframe environment.

Identify key mainframe data sources (SMF, RMF, Syslog, application logs) for operational anomaly detection.

Explain how machine learning can be used on operational data to detect anomalies and predict failures.

Position IBM Z Anomaly Analytics and Watson AIOps within an integrated operations workflow.

Outline the architecture of an AI-assisted incident triage and root-cause analysis pipeline.

Describe how predictive modeling can be applied to forecast batch job completion times against SLAs.

Analyze the benefits and challenges of implementing an AIOps solution for a large mainframe shop.

Formulate a business case for adopting AIOps, focusing on SLA improvement and MTTR reduction.

Lead a mock Sev-1 batch failure scenario, demonstrating incident command, technical triage, and stakeholder communication.

Conduct a senior-level code review of a COBOL/JCL submission, providing constructive, actionable feedback.

Analyze a set of CICS/DB2/batch monitoring reports to isolate and explain a cross-component performance bottleneck.

Select and defend a modernization strategy (rehost/refactor/rebuild) for a sample workload, including risk, cost, and ROI analysis.

Design and defend a z/OS Connect API enablement plan for a legacy application to a mock architectural review board.

Evaluate and justify a choice between modernization tools (e.g., BluAge, watsonx) for a given scenario, including a build-vs-buy analysis.

Answer senior behavioral questions related to leadership, conflict resolution, and mentoring using the STAR method.

Participate in a comprehensive mock interview drill sampling technical, architectural, and behavioral questions from this syllabus.