Tasks of the transport dispatcher program RDDIMPDP
Each export from a source system and each import into a target system can be split into different phases or transport steps. Some of these steps are performed by external programs (tp and R3trans) and some by ABAP programs within the system. The task of the program RDDIMPDP is to start and monitor all steps performed by ABAP programs.
The external transport control program tp uses entries in the tables TRBAT and TRBATC to pass information on the transport steps. This information includes the type of transport step (function), the transport requests involved and possibly the client where the transport step is performed. tp then triggers an SAP event of the transport dispatcher to start RDDIMPDP as a background job in client 000.
To perform the transport steps, RDDIMPDP starts the corresponding ABAP programs in separate background processes. Information on the background processes that have been started is placed in the table TRJOB. This table is then used later to check the status of the processes. If a step ends successfully, or if it runs with errors, then an appropriate entry is made in the tables TRBAT and TRBATC. tp analyzes this information and then deletes it from the tables TRBAT and TRBATC.
Client-specific transport steps
Transport steps are usually performed in client 000, since the corresponding programs mostly edit cross-client data only. Only the export and import of ADO objects (application-defined objects), such as number ranges, takes place in other clients (the export in the source client of the corresponding transport request or change request; the import in the same client as the export, if no target client is specified).
The program RDDIMPDP in client 000 recognizes that an action must be performed in another client and triggers a client-specific SAP event. This starts RDDIMPDP as a background job in this client. RDDIMPDP then starts the corresponding ABAP program in a separate background job.
Names of the background jobs
Use this overview of the various background jobs involved in the transport to monitor the progress of the transport in the Job Overview (Tools -> CCMS -> Jobs -> Maintenance (Transaction SM37)).
Additional note
If you also want to display jobs that are not scheduled for a definite start time, enter * in the field or after event: on the job overview selection screen.
The transport dispatcher RDDIMPDP is scheduled as an event-controlled background job. To help identification, the name of the job contains the client where it is scheduled. The triggering SAP event is also client-specific.
Client Job name triggering event with parameter 000 RDDIMPDP SAP_TRIGGER_RDDIMPDP nnn RDDIMPDP_CLIENT_nnn SAP_TRIGGER_RDDIMPDP_CLIENT nnn
The ABAP programs started by RDDIMPDP depend on the transport step entered in the function field of the table TRBAT:
Function Job name Description of the transport step J RDDMASGL Activates ABAP Dictionary objects M RDDMASGL Activates matchcodes and lock objects S RDDDIS0L Analyzes the database objects for conversion N RDDGEN0L Converts database objects Y RDDGEN0L Converts matchcode tables X RDDDIC0L Exports ADO objects D RDDDIC1L Imports ADO objects E RDDVERSE Executes pre-export methods (such as creation of versions) W RDDVERSI Creates versions before the import V RDDVERSL Updates version management before import F RDDVERSK Creates versions after the import R RDDEXECL Executes post-import methods G RDDDIC3L Generates ABAP programs and screens
Requirements
To enable the transport to run without errors, the program RDDIMPDP must be scheduled as a background job in client 000 and in all clients where data is being imported or exported. This job is scheduled automatically when you use the standard client copy tools to create a new client. However, you can schedule the job at any time, for example, if you only find out that it is not scheduled when the transport is already running.
To schedule the program RDDIMPDP as a background job, log on to the appropriate client as a user with CTS administration authorization and execute the program RDDNEWPP in the ABAP Editor (Tools -> ABAP Workbench -> Development -> ABAP Editor (transaction SE38)).
RDDIMPDP starts the transport steps in separate background processes. This means that there must be (at least) two background processes available in the R/3 System (profile parameter rdisp/wp_no_btc). If the system runs on multiple application servers you can distribute these background processes across them.
The transport control program tp must be able to communicate with the message server of the SAP System to be able to trigger the SAP event for starting RDDIMPDP. This is guaranteed if tp is started on an application server of the SAP System where the export or import takes place.
This is always the case for imports and exports started within the SAP System (from the Transport Organizer or the Transport Management System). For imports started at the operating system level, it depends on the host where tp is called.
