sap-s4-migration

## 1. Approach Decision Tree ``` Q1: Keep existing configuration and historical data? YES → System Conversion (Brownfield) NO → New Implementation (Greenfield) SOME → Selective Data Transition (Bluefield / Shell Conversion) Q2: Target deployment model? On-premise → Full flexibility; custom code with restrictions RISE (PCE) → Managed infrastructure; same S/4HANA functionality S/4HANA Cloud PE → Clean Core only — no modifications, no ABAP CBO ``` ### Approach Comparison | Aspect | Brownfield | Greenfield | Bluefield | |--------|-----------|-----------|----------| | Data migration | Automatic (SUM/DMO) | Manual (LTMC) | Selective | | Configuration | Carried over | Redesigned | Mix | | Custom code | Must remediate | Can replace with standard | Must remediate | | Project duration | Shorter | Longer | Longest | | Risk | Medium | Lower (for processes) | High (complex) | | Best for | Large existing systems | Major transformation | Demerger / consolidation | --- ## 2. SAP Readiness Check — Critical Simplification Items ### FI / Accounting | Item ID | Impact | Description | Resolution | |---------|--------|-------------|-----------| | S4TWL_ACDOCA | High | Universal Journal mandatory; BSEG becomes secondary | Ensure New GL active; run Universal Journal migration | | S4TWL_NEWGL | High | Classic GL not supported — New GL must be active | Activate New GL in ECC before SUM run | | S4TWL_ASSETACCTG | High | New Asset Accounting mandatory; Classic AA re...