For configuring communication with backend systems from SAP SRM first we should define following steps:
Defining Logical system:
Define logical system in below mentioned path:
SPRO → Supplier Relationship Management → SRM Server → Technical Basic Settings → ALE Settings (Logical System) → Distribution (ALE) → Basic Settings → Logical Systems → Define Logical System.
Defining RFC destination:
SAP Enterprise Buyer communicates with any backend system using RFC.
Define RFC connections in SRM in below path:
Supplier Relationship Management → SRM Server → Technical Basic Settings
→ Define RFC Destinations.
If we have more than one R/3 backend system, define an RFC destination for each one.
We also have to define RFC destination for SAP Enterprise buyer in R/3.
Defining Backend System
Please follow below path to define backend systems in SAP SRM:
SPRO → Supplier Relationship Management → SRM Server → Technical Basic Settings → Define Backend Systems.
For creating follow-on documents in SRM: Enter the logical system, destination, system type of the SRM system and define SRM system as local.
For creating follow-on documents in backend system: Enter the logical system, destination and system type of the backend system and select the RFC indicator if the logical system is RFC-compatible.
Now connections are defined from SRM to R/3.We can determine which backend system should be used to create follow-on documents as mentioned in my previous blog determining backend systems.