EWM Migration Strategies: WM to EWM
With SAP's roadmap moving toward S/4HANA, many organizations face the inevitable: migrating from legacy WM to Extended Warehouse Management. Here's how to approach it successfully.
Migration Approaches
1. Brownfield (System Conversion)
- Convert existing ECC to S/4HANA
- WM converted to stock room management or embedded EWM
- Lower risk for simpler warehouses
- Carries forward existing configuration and customizations
2. Greenfield (New Implementation)
- Fresh EWM implementation
- Opportunity to redesign processes
- Clean slate without technical debt
- Higher effort but better long-term result
3. Bluefield (Selective Data Transition)
- Hybrid approach
- Migrate select data and configuration
- Redesign where beneficial
- Balance between risk and improvement
Key Planning Considerations
- Architecture decision: Embedded vs decentralized EWM
- RF transaction mapping: User experience continuity
- Custom development: ABAP to clean core assessment
- Integration points: Interfaces needing redesign
- Data migration: Master data and open documents
Common Gaps
Functionality that works differently in EWM:
- Batch management approach
- Serial number handling
- Storage unit management
- Custom transaction codes
Cutover Strategy
Options for go-live:
- Big bang: All warehouses simultaneously
- Phased: One warehouse at a time
- Parallel run: Both systems temporarily
Success Factors
- Executive sponsorship and change management
- Thorough process documentation
- Comprehensive testing including peak scenarios
- User training with hands-on RF practice
- Hypercare support post go-live
Migration is a business transformation, not just a technical upgrade.