In our blog that examined the ERP industry’s shift from on-premises systems to cloud-based delivery, we looked at what the trend means for IT leaders and integration managers. Now, with end of mainstream maintenance for ECC 6.0 on the horizon, we want to discuss what migrating to SAP S4/HANA means for the business and system integration tech stack (EDI, EAI, MFT, APIs).
In this article, we’re going to explore the known challenges to EDI documents and integration workflows that can bedevil migrating from ECC 6.0 to S/4HANA. And we also list the steps you can take to avoid them.
Lastly, we outline how a firm like Remedi can support you during the migration to ensure it proceeds with minimal disruption to operations, revenue, and trading partners.
KEY TAKEAWAYS
- EDI and Integration Challenges When Migrating to S4/HANA
- IDoc Format Changes & Mapping Impacts
- Output Management Overhaul: BRF+ vs. NAST
- Partner Profile Reconfiguration
- Master Data Conversion (Business Partner Model)
- Middleware & Translator Adjustments
- Testing Complexity Across Systems & Partners
- Authorization & Role Management Gaps
- Custom Enhancements & User Exits Compatibility
- Performance Shifts with HANA Processing
- Disruption to 3PL, WMS, and Other External/Internal Integrations
- Dual-System Dependencies & Resource Constraints
- How a Firm Like Remedi Can Help
What Are the EDI/Integration Challenges We Will Face When Migrating to SAP S/4HANA?
ERP cloud migrations, whether it’s from SAP ECC 6.0 to SAP S/4HANA or another system are more than platform moves. They’re more like a live brain transplant that requires completely rewiring all the patient’s neural pathways— without disrupting their motor function, speech or memories.
In the above analogy, the EDI maps and integration points represent the neural pathways. Reviewing the following known challenges can prepare you and your team to anticipate and navigate the obstacles your current EDI tech stack will face along the S/4 transition journey.
Should you elect to work with an outside consultant such as Remedi to mitigate these challenges, you can let your partner take the lead, ask them to give input, or have them follow your direction.
Challenge 1: IDoc Format Changes & Mapping Impacts
Challenge: Be aware that S/4HANA can change the structure of the iDoc format. How so? Fields are longer, new segments added, and some segments deprecated.
Impact: Existing EDI maps break or worse, silently misbehave (e.g., truncated data, unmapped fields).
Why It Matters: Even subtle IDoc changes in key messages like INVOIC02 or ORDERS can ripple through supply chains. Inaccurate mappings can lead to failed transactions, chargebacks, or customer dissatisfaction. Not to mention having a negative impact on partner SLAs, integration reliability, and overall migration risk.
Steps to Mitigate:
- Perform a detailed comparison of ECC and S/4 IDoc versions for each message type.
- Update EDI maps and test each transaction type end-to-end.
- Use test IDocs and partner simulations before go-live to validate translations.
Challenge 2: Output Management Overhaul (NAST vs. BRF+)
Challenge:
S/4 introduces BRF+ (Business Rule Frame Plus) to replace classic NAST message control for triggering EDI outputs. For those who don’t know, NAST is the technical name of the table used for output message control in legacy systems.
The table holds information about output types, transmission method, and partner function among other details.
Impact:
Companies must reconfigure EDI output logic from scratch. Early versions of BRF+ lacked full IDoc support, which often forced a fallback to NAST for business-critical flows.
Why It Matters:
If output logic fails post-migration, trading partners may not receive critical docs like ASNs or invoices, causing order disruptions and SLA violations.
Steps to Mitigate:
- Inventory all NAST-based outputs and map to S/4 equivalents.
- Decide case-by-case whether to use BRF+ or retain legacy NAST for specific IDocs.
- Confirm IDoc output support within the new framework using SAP OSS Notes.
Challenge 3: Partner Profile Reconfiguration
Challenge:In S/4HANA, the EDI partner profile setup via WE20 becomes more complex. You not only define inbound/outbound parameters for a partner but must also account for multiple partner types—including Business Partner (BP), Logical System (LS), Vendor (LI), Customer (KU), and more—each requiring their own profile setup.
Impact: Without accurate setup, IDocs fail to post or get routed incorrectly.
Why It Matters: Partner profiles are the tracks your IDocs run on—if they’re misconfigured in S/4, nothing moves. Entire document flows can stall without warning.
Steps to Mitigate:
- Extract a complete list of current partner profiles and ports from ECC.
- Validate mappings, partner types, and logical system names for the S/4 environment.
- Build a reusable partner onboarding checklist for post-migration validation.
Challenge 4: Master Data Conversion (Business Partner Model)
Challenge: S/4HANA replaces the separate customer and vendor records in ECC with a unified Business Partner (BP) model. This means all customer/vendor master data must be migrated into BP entities—each with the correct roles (e.g., "Customer," "Supplier") assigned. SAP’s Customer-Vendor Integration (CVI) framework handles this technically, but if roles are missing or mappings are incomplete, EDI processes tied to those records can fail.
Impact: Outbound EDI messages may carry new codes partners don’t recognize. Inbound messages might fail without remapping. Also, if BP records are missing key roles or identifiers, EDI messages may fail to generate, route incorrectly, or be rejected by partners.
Why It Matters: These mismatches can disrupt core processes like order-to-cash and procure-to-pay. Unfortunately, these issues tend to surface only after go-live. If master data and EDI aren't synchronized, partner communications break down—leading to lost orders, incorrect shipments, and costly rework.
Steps to Mitigate:
- Cleanse and standardize ECC customer and vendor records prior to conversion.
- Use SAP CVI Cockpit to assign correct roles and maintain legacy number references.
- Cross-reference new BPs in middleware or maps to ensure partners recognize them.
- Test EDI flows for both outbound and inbound messages using converted master data.
- Notify trading partners of any externally visible changes before cutover.
Challenge 5: Middleware and Translator Adjustments
The way S/4HANA changes IDoc structures and how messages are packaged and monitored often requires updates to middleware platforms (like IBM Sterling B2B Integrator, Boomi, Seeburger) and EDI translators.
Segment changes such as E1EDP01, MATNR_LONG and new packaging behavior require revisiting mapping logic—otherwise you risk mismatches between SAP and your integration layer.
SAP Community members confirm that after conversion, IDoc segment versions often change, and middleware will not process them correctly until the updated definitions are imported and remapped.
Impact: Unadjusted mappings, outdated adapters, or incorrect bundling rules can result in failed exchanges, corrupt messages, or disconnected partner communication.
Why It Matters: Middleware is invisible until it breaks—and when it breaks, EDI stops. Updating IDoc dictionaries and re-pointing connections is essential to maintain flow.
Steps to Mitigate:
- Inventory all IDoc types and compare ECC vs. S/4HANA structures.
- Update middleware IDoc definitions to match new segments and change map logic as needed.
- Validate bundling settings so IDocs are grouped correctly in messages.
- Leverage S/4’s Fiori/AIF monitoring to trace IDocs through middleware.
Challenge 6: Testing Complexity Across Systems & Partners
Challenge: We can’t stress this point enough. Regression testing must span multiple teams, platforms, and trading partners. This applies especially when ECC and S/4HANA are running in parallel during the migration. With changes to IDoc structures, partner profiles, and middleware mappings, even small gaps in testing can lead to errors that surface in production.
Impact: Lack of structured testing causes data mismatches, posting errors, and partner rejections post go-live. Here’s a real-world example: A missing segment in an 856 Advance Shipping Notice causes an erroneous send. As a result, the distribution center rejects inbound deliveries, which delays fulfillment and incurs chargebacks.
Why It Matters: EDI is only successful when all parties sync. Message failures or inaccuracies not only can delay payments and shipments, but they also undermine customer or partner confidence. Diligent testing protects important relationships and the company’s bottom line.
Steps to Mitigate:
- Build a partner-by-transaction test matrix to ensure all flows are exercised.
- Conduct dual-system testing in ECC and S/4 during overlap periods.
- Validate acknowledgments (e.g., 997s, functional confirmations) are flowing correctly in both directions.
- Use real-world test data and scenarios that reflect your highest-risk transactions.
Challenge 7: Authorization & Role Management Gaps
Challenge: Users often lose access to familiar EDI tools like WE02, WE05, and WE19 when transitioning to S/4HANA. This can happen if role-based authorizations aren't rebuilt to reflect changes in transaction codes or EDI functionality.
Impact: Teams can’t view or reprocess IDocs, leading to delays in error resolution and operational friction during cutover.
Why It Matters: In S/4HANA, even seasoned users can lose visibility into IDoc queues if roles aren’t reassigned. Without access to key tools like WE02 or Fiori equivalents, EDI teams are stuck flying blind when errors hit.
Steps to Mitigate:
- Define required EDI roles early, including traditional T-Codes and Fiori app equivalents.
- Use SAP Fiori apps for functions that no longer have GUI transactions in S/4.
- Test and validate access for all EDI functions before go-live to avoid role-based disruptions.
Challenge 8: Custom Enhancements & User Exits Compatibility
Challenge: Z-segments and user exits built into ECC often don’t function as expected in S/4HANA, especially when underlying IDoc structures or processing logic have changed due to data model simplification. You must review and revalidate these enhancements during migration.
Impact: Custom logic must be refactored or replaced—otherwise key document flows (like 850-to-Sales Order) may fail silently.
Why It Matters: These enhancements are often hard-coded into order-to-cash or procure-to-pay workflows. As such they are critical for enforcing business rules and routing logic. Losing them can seriously damage the business. Negative impacts include impeding cash flow and creating confusion that erodes trust with customers and trading partners.
Steps to Mitigate:
- Inventory all custom code tied to EDI and IDoc processing.
- Work with SAP developers to assess which exits, Z-segments, or enhancements need to be refactored or rebuilt.
- Test high-volume and edge-case scenarios to ensure custom logic behaves as expected in S/4HANA.
Challenge 9: Performance Shifts with HANA In-Memory Processing
Challenge: S/4HANA’s in-memory HANA database eliminates traditional disk I/O delays but there’s a caveat. The change introduces new performance considerations and potential for bottlenecks. Background job scheduling, IDoc queue handling, and CPU/memory utilization all play a larger role in determining throughput. Legacy tuning parameters from ECC may no longer apply.
Impact: If job scheduling and IDoc throughput aren't tuned for S/4, high-volume transaction windows (e.g., order spikes, month-end invoicing) may result in slow processing, delayed confirmations, or stuck queues.
Why It Matters: HANA’s in-memory speed may solve the old disk bottlenecks but in EDI-heavy environments, new performance ceilings emerge. If background jobs and IDoc queues aren’t tuned, faster processing can still mean slower results.
Steps to Mitigate:
- Baseline current IDoc loads in ECC and set throughput targets for S/4.
- Tune HANA and ABAP work processes to handle expected volume under peak conditions.
- Monitor queues (e.g., SM58) and memory metrics using HANA Cockpit or transaction ST03N.
- Test peak-volume scenarios before go-live and adjust batch schedules or parallel processing settings as needed.
Challenge 10: Disruption to 3PL, WMS, and Other External/Internal Integrations
Challenge: Legacy integrations with logistics systems (WMS, 3PL) often rely on tightly coupled IDoc exchanges. Examples include delivery creation, shipping confirmations, and goods movement updates. These processes use IDocs like SHP_IBDLV_SAVE_REPLICA and SHP_IBDLV_CONFIRM_DECENTRAL, which must be retested and revalidated in the S/4HANA environment.
Impact: These IDoc-based integrations require careful revalidating to prevent adverse downstream outcomes. These can include stalled warehouse activities, failed confirmations, or delayed shipments. Any of which may degrade customer satisfaction and operational efficiency.
Why It Matters: Distribution is unforgiving. Misfiring 3PL EDI processes can derail fulfillment, erode trust, and damage customer relationships. As well as incur SLA fines and fees for manual troubleshooting.
Steps to Mitigate:
- Audit current WMS/3PL integrations to identify all ECC-specific IDoc types in use.
- Retest core message flows like outbound delivery creation and inbound receipt confirmations using S/4 test environments.
- Engage 3PL and WMS providers early to coordinate validation and cutover planning.
- Confirm consistent results across typical and exception scenarios to ensure operational continuity.
Challenge 11: Dual-System Dependencies & Resource Constraints
Challenge: Many organizations run ECC and S/4HANA in parallel during migration. They also continue EDI operations. This means maintaining dual environments, maps, and teams simultaneously, but the approach comes with risks.
For example, a trading partner onboarding during cutover may receive two different order confirmations—one from ECC and one from S/4—requiring extra middleware logic and partner coordination.
Impact: Teams end up duplicating EDI map sets, test cases, and error-handling routines—under tight deadlines and constrained resources. Running two systems in parallel doubles your risk of EDI errors. Without clear ownership, map drift and missed messages are almost guaranteed.
Why It Matters: With multiple systems in play, testing and dual maintenance of EDI maps becomes a full-time job. One misstep creates cascading failures across environments.
Steps to Mitigate:
- Sequence EDI work separately from core SAP migration or clearly designate a dual-maintenance window.
- Leverage middleware translation layers to unify partner-facing outputs, regardless of originating system.
- Assign a sole EDI owner to manage synchronization, error resolution, and partner communication across both environments.
How a Firm Like Remedi Can Help During the Migration from ECC to S/4
With our flexible consulting and staffing model, Remedi can support your migration to S/4 in a variety of ways.
Re‑Mapping & Testing for S/4
In this scenario, Remedi would take the lead on responsibilities such as map redesign, partner re‑ingestion, and testing, freeing internal teams to focus on the ERP migration.
Legacy System Monitoring & Support
Another migration support option to consider is a managed services arrangement. With this approach, you engage Remedi to manage all or a portion of your current EDI environment while migration work proceeds.
Flexible Support Options
Whether consulting, staff augmentation, or long-term support, we can design a talent solution that’s tailored to your budget, timeline, and internal capacity.
For more information on how we can support your EDI needs during a migration to S/4HANA, reach out here.
