A business system will define for the EWM (own business system) and for each ERP system that is connected to EWM system. The SAP EWM system stores the business system in the document flow tables of the cross-system and cross partner document flow and helps to determine to which ERP system a document belongs.
Business System is mapped to their corresponding logical systems, because the delivery documents sent from SAP ERP to SAP EWM system contain only the logical system number of the SAP ERP system. The mapping helps to determine the business system based on logical system so that warehouse request document in EWM can be updated with the corresponding business system.
In this step, you define a dummy logical system for the embedded EWM application. This setting is required for creating the distribution model needed for setting up the qRFC communication. The logical system can be created from Transaction BD54, which can also be accessed from IMG path SAP NetWeaver > Application Server > IDoc Interface/Application Link Enabling (ALE) > Basic Settings > Logical Systems > Define Logical System.
Note: Although EWM is embedded in SAP S/4HANA, a dummy logical system still needs to be created to establish communication between embedded EWM and SAP S/4HANA. Standalone SAP EWM, however, would require you to create an actual logical system for the SAP EWM system.
4. Assign the Logical System to the Client
In this step, you assign the logical system of SAP S/4HANA to the client. The assignment can be made from IMG path SAP NetWeaver > Application Server > IDoc Interface/Application Link Enabling (ALE) > Basic Settings > Logical Systems > Assign Logical System to Client. You can skip this step if the SAP S/4HANA logical system is already assigned to a client.