iSeries server as the target server for DDM


The iSeries™ target DDM (or TDDM) is actually a job that runs a DDM-related target server program. It is started when the source server sends a program start request (an SDDM).

For source iSeries servers, the program start request is started on the source server using information contained in the IBM-supplied intersystem communications function (ICF) file for DDM. The remote location information in the DDM file being accessed is used to send the program start request to the appropriate target server.

The attributes of the target job are determined by the values specified on the Add Communications Entry (ADDCMNE) command, which is used on the target server to add a communications entry to the subsystem description used for the job. This command identifies the device description, the job description (including the library list for the target job), and the default user profile to be used by the subsystem.

For an iSeries Access Family connection, the routing entry in the QIWS subsystem for DDM (CMPVAL ('DDM')), along with the device description the personal computer is connected to, is used to obtain the attributes of the target job.

After it is started, the TDDM does the following things:

The following figure shows the basic parts on the target iSeries server that are involved in processing the requested destination file.

The TDDM runs as a separate batch job, just as any other user APPC, TCP/IP, or iSeries Access Family target application. A new TDDM, using additional target server resources, is started for each distinct source server program start request received by the target server. There is one target job for each DDM conversation. Each TDDM can handle access requests for multiple files in the DDM conversation. Figure 1. iSeries server as the DDM target system

This figure is described in the text of this section.

The subsystem, user profiles, and server resources to be used by the TDDM are defined the same as they are for other types of jobs.


Parent topic:

Additional DDM concepts


Related concepts

Parts of DDM: Target DDM