Outbound ALE from SAP

The R/3 adapter can retrieve output from many different SAP R/3 systems as defined by the maps executing on either the Launcher or the Command Server.

To retrieve output from an SAP R/3 system into a non-SAP R/3 system

  1. One of the application modules of SAP generates a request for IDoc data. This request can be on demand by using ALE, or based on events such as those defined with Output Determination. This generates the IDoc Data.
  2. This request is directed to the partner profile. The configuration of the partner profile determines the port designation.
  3. The defined port determines whether this is a file-based communication or an ALE memory-based communication. For memory-based communications, the port designates the RFC Destination.
  4. The RFC Destination determines that the communication method is Registration (or Start) and also the physical parameters of the external system.
  5. The IDoc data is passed to the gateway. Inquiry into the IDoc logs will indicate a message Passed to Port OK.
  6. The communication layer connects to the external system as configured in the RFC Destination. If the communication is successful, the outbound communications start. If the communication fails, the RFC Transaction monitor (SM58) will indicate a communication error.
  7. For successful connections, the communication layer will connect to the SAP R/3 server functionality of the R/3 adapter. The communication layer makes the RFC calls to establish the communication, perform the TID management functions, and pass the IDoc data.
  8. The IDoc data is passed to the R/3 adapter by means of memory. This implies that the external system and user have adequate memory resources on the external platform. The RFC layer requires up to twice the IDoc data size so that there is sufficient memory to decompress the IDoc data. (The data is transmitted on the network in compressed form to increase network performance.) In addition, it is required to have memory equal to the data size to hold the data in memory. The data is held from the time it is received until it can be processed by the appropriate map(s). This requires careful planning if using the Launcher, especially if the maps have low throughput (or are single-threaded) because maps in the init pending state are consuming memory for staged IDocs.
  9. When the R/3 adapter has received the IDoc data, a backup file of IDoc data is created if the -B adapter option is used. The transformation server begins the validation of all input files, building temporary work files as necessary.
  10. The transformation server builds all output data and connects to any non-file systems via resource adapters.
  11. If the map completes successfully, the R/3 adapter closes the connection from SAP. If the map does not complete successfully, a rollback file of the IDoc data is created if the OnFailure setting is set to Rollback for the ALE input.