What Options to Consider if Legacy LE-WM is Not Compliant for Stock Room Management during S/4HANA Migration?


Introduction

Many customers have started their S/4HANA journey by adopting to one of the approaches like system conversion, green field or mix and match-hybrid approach. This blog is intended to further share my personal insights on the journey to S/4HANA, especially when Stock Room Management is found to be not compliant during S/4HANA pre-migration checks.

For those legacy ECC implementations where LE-WM is predominantly used, in order to continue leveraging on the Basic SAP WM features beyond 2025, the option of using Stock Room Management (StRM) is provided by SAP.

My previous blog “Should I migrate from LE-WM to Stock Room Management?” helped in providing the decision criteria for moving to LE-WM successor solution options during S/4HANA migration. It also mentioned the usage of scope compliance check (SAP note 2882809) whether the legacy WM implementation is using the functional scope that is included in the SAP license of Stock Room Management.

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Example of output from scope compliance check report

The aim of this blog is to summarize the recommended approaches for those specific functionalities which are found to be not compliant any longer with the Stock Room Management (StRM).

1. Warehouse Control Interfaces

The third party external systems which are integrated with LE-WM via ALE IDOC Interfaces is no longer a part of the the SAP recommended architecture anymore within SAP S/4HANA.

During system conversion to S/4HANA, if you decide to continue using these interfaces of LE-WM, then use the compatibility package (refer SAP note 2269324).

Due to StRM incompatibility, If you decide using S/4HANA EWM then the migration of LE-WM to EWM will come into picture. EWM out-of-the box provided WCU Integration can be leveraged here.

EWM-WCU Interface uses tRFC (transaction RFC) approach instead of traditional synchronous RFC, this allows the S/4HANA EWM to storage the data in a buffer area before transmission to the external system, this helps in message queuing. The data is transmitted using Intermediate Documents (IDOC). For Inbound messages received the external non-SAP system will be responsible for buffering the data (queuing method).

2. Decentralized WM

One of the very wide use of decentralized-WM in SAP implementations across different industries is for example in case of Integration with 3PL managing your stock in a standalone external WMS applications.

If you are using standalone decentralized SAP system which manages your stock and the Central S/4HANA ERP is supposed to report all the inventory and goods movements, delivery communications etc. then the decentralized WM can be used as a separate configuration within S/4HANA for integration with these standalone WM decentralized applications.

If your legacy ECC system already used DWM Integration and found that scope compliance check has identified it as failing in the check of Stock Room Management scope, you just need to use the same DWM component by activating it again in S/4HANA ERP by using the same techniques for smoother migration. This is possible by freshly assigning the plant and storage location within S/4HANA ERP to a warehouse number and further by activating this warehouse number with decentralized WM. By doing so, the standard out-of-the box DWM integration techniques can be leveraged.

SAP S/4HANA like it’s predecessor supports ALE IDoc based Interface for Master Data Integration with DWM, mainly for material master, batch master, classification, customer and vendor master objects. For transactional data integration, asynchronous BAPI technique is used via IDOCs generated from BAPI (example: message type SHP_OBDLV_SAVE_REPLICA to send outbound deliveries).

3. Wave Management

During Stock Room Management Compliance Check, if it is found that you are using wave management or collective processing of LE-WM then are two options to mitigate such impacts:

Option 1: Continue using LE-WM in compatibility mode during S/4HANA conversion for a limited period of time (refer compatibility conditions SAP note 2269324)

Option 2: Migrate to SAP S/4HANA Advanced-EWM and use EWM out-of-the box wave management functionality.

4. Task and Resource Management (TRM)

During Stock Room Management Compliance Check, if it is found that you are using Task and Resource Management functionality of LE-WM then are two options to mitigate such impacts:

Option 1: Continue using LE-TRM in compatibility mode during S/4HANA conversion for a limited period of time (refer compatibility conditions SAP note 2269324)

Option 2: Migrate to SAP S/4HANA EWM and use EWM standard out-of-the box functionalities Resource Management, Queue Management, Mobile Data Entry and use EWM Warehouse Monitor to monitor task and resource assignment and management during  warehouse operations.

5. Cross-docking

During Stock Room Management Compliance Check, if it is found that you are using cross docking from legacy WM then are two options to mitigate such impacts:

Option 1: Continue using cross docking (component- LE-WM-CD) in a compatibility mode during S/4HANA conversion for a limited period of time (refer compatibility conditions SAP note 2269324)

Option 2: Migrate to SAP S/4HANA Advanced-EWM and use EWM standard out-of-the box functionalities planned cross-docking or opportunistic cross-docking. Planned cross-docking offers solution options like transportation cross-docking and merchandise cross-docking whereas the  opportunistic cross-docking provides different solution scenarios like Push Deployment (PD), Pick From Goods Receipt (PFGR) & EWM-Triggered Opportunistic cross-docking.

6. Yard Management

During Stock Room Management Compliance Check, if it is found that you are using yard management from legacy WM then are two options to mitigate such impacts:

Option 1: Continue using yard management within legacy WM (component- LE-WM-CD) in a compatibility mode during S/4HANA conversion for a limited period of time (refer compatibility conditions SAP note 2269324)

Option 2: Migrate to SAP S/4HANA Advanced-EWM and use EWM provided Yard Management functionality as part of Shipping and Receiving cross-processes. It provides integration with check points, parking space and doors where the Transportation Units (TUs) and vehicles will arrive & depart during unloading and loading of the goods in yard.

7. Value Added Services

During Stock Room Management Compliance Check, if it is found that you are using value added service management from the legacy WM then are two options to mitigate such impacts:

Option 1: Continue using value added services within legacy WM (component LE-WM-VAS) in a compatibility mode during S/4HANA conversion for a limited period of time (refer compatibility conditions SAP note 2269324)

Option 2: Migrate to SAP S/4HANA Advanced-EWM and use EWM Value Added Service (VAS) functionality. EWM VAS functionality offers different solution scenarios involving Kit to Order. Kit to Stock and Reverse Kitting. EWM VAS processes can be employed in Inbound or in Outbound processes.

Conclusion:

Value Added Services, Yard Management, Cross Docking, Wave Management or Collective Processing, Decentral WM, Warehouse Control Interface and Task & Resource Management from legacy LE-WM are not in the target architecture of S/4HANA on-premise solution. Basically customers migrating to S/4HANA have two options i.e. either continue using these solution features for a limited period of time or implement EWM functionalities to replace the legacy solution.

References:

2882809 – Scope Compliance Check for Stock Room Management

Sub-notes

2889638 S4TWL – Value Added Services
2889637 S4TWL – Yard Management
2889636 S4TWL – Cross Docking
2889652 S4TWL – Wave Management / Collective Processing
2889540 S4TWL – Decentral WM
2889468 S4TWL – Warehouse Control Interface
2889253 S4TWL – Task & Resource Management

Blog: Stock Room Management Comparison with EWM

Blog: Should I Migrate from LE-WM to Stock Room Management?