mainframe-to-cloud

name	mainframe-to-cloud
enabled	true
description	Use when performing mainframe to cloud — provides a structured methodology for migrating mainframe workloads (COBOL, JCL, CICS, IMS) to cloud-native platforms. Covers code analysis, automated conversion, data migration from hierarchical and VSAM stores, batch job modernization, and phased cutover with parallel validation.
required_connections	[{"prefix":"mainframe","label":"Mainframe System"},{"prefix":"cloud-provider","label":"Target Cloud Provider"}]
config_fields	[{"key":"mainframe_platform","label":"Mainframe Platform","required":true,"placeholder":"e.g., IBM z/OS, AS/400, Unisys"},{"key":"primary_languages","label":"Primary Languages","required":true,"placeholder":"e.g., COBOL, PL/I, Natural/ADABAS"},{"key":"target_language","label":"Target Language/Platform","required":false,"placeholder":"e.g., Java, .NET, cloud-native containers"}]
features	["CLOUD_MIGRATION","MAINFRAME","MODERNIZATION"]

Mainframe to Cloud Migration Plan

Phase 1: Mainframe Discovery

1. Inventory all mainframe assets
   • Programs (COBOL, PL/I, Assembler, Natural)
   • JCL jobs and batch schedules
   • CICS/IMS online transactions
   • Databases (DB2, IMS DB, VSAM, ADABAS)
   • Copybooks and data structures
   • Inter-system interfaces (MQ, FTP, CICS MRO)
2. Analyze code complexity and dead code
3. Map business processes to technical components
4. Document batch job dependencies and scheduling

Workload Classification

Component	Type	Lines of Code	Complexity	Business Criticality	Migration Approach
	Batch/Online/DB		Low/Med/High	Critical/Important/Low	Rehost/Refactor/Replace

Phase 2: Migration Strategy Selection

Decision Matrix

Approach	Risk	Cost	Timeline	Modernization Level	Best For
Rehost (emulation)	Low	Medium	Short	Minimal	Quick lift
Automated refactor	Medium	Medium	Medium	Moderate	COBOL to Java
Manual rewrite	High	High	Long	Maximum	Complex logic
Replace with COTS/SaaS	Medium	Variable	Medium	High	Standard functions

1. Select approach per workload based on business value and risk
2. Identify workloads suitable for automated conversion tools
3. Plan for workloads requiring manual rewriting
4. Determine which functions to replace with SaaS solutions

Phase 3: Foundation & Tooling

1. Set up cloud landing zone for mainframe workloads
2. Configure mainframe-to-cloud conversion tools
3. Establish connectivity between mainframe and cloud
4. Set up parallel testing environment
5. Create automated regression test suites from production data

Phase 4: Code Migration

1. Convert or rewrite programs in priority order
2. Migrate copybooks to modern data structures
3. Transform JCL batch jobs to cloud-native orchestration
4. Modernize online transactions to APIs or web services
5. Validate each converted component against original behavior

Phase 5: Data Migration

1. Design target data models (relational, NoSQL)
2. Build ETL pipelines for data transformation
3. Migrate DB2/IMS/VSAM data to cloud databases
4. Handle EBCDIC to ASCII/Unicode conversion
5. Validate data integrity with row counts and checksums

Phase 6: Parallel Run & Cutover

1. Run mainframe and cloud systems in parallel
2. Compare outputs of batch jobs between environments
3. Validate online transaction responses match
4. Execute cutover during planned maintenance window
5. Keep mainframe available for rollback period

Counter-Rationalizations

Shortcut	Counter	Why
"We can skip some steps for this case"	Adapt the workflow steps, don't skip them	Skipped steps are where incidents and oversights originate
"The user seems to already know what to do"	Complete all workflow phases with the user	The workflow catches blind spots that experience alone misses
"This is a minor case, full process is overkill"	Scale the process down, don't turn it off	Minor cases become major when unstructured; the process scales, not disappears
"I'll fill in the details later"	Complete each section before moving on	Deferred details are forgotten; real-time capture is more accurate
"The template output isn't necessary"	Always produce the structured output format	Structured output enables comparison, audit trails, and handoff to other teams

Output Format

• Asset Inventory: Complete mainframe program and data catalog
• Migration Strategy Document: Approach per workload with justification
• Conversion Report: Automated and manual conversion results
• Parallel Run Results: Comparison reports between mainframe and cloud
• Cutover Runbook: Step-by-step production migration procedures

Action Items

• Complete mainframe asset discovery and classification
• Select migration approach per workload
• Execute proof of concept with representative workloads
• Build and validate automated test suites
• Migrate workloads in priority waves
• Run parallel validation for each wave
• Decommission mainframe after full stabilization