Subsystems used for server Jobs

The server jobs are configured to run in different subsystems, depending on their function.

The following are the subsystems used for the server jobs.

QSYSWRK

All the daemon jobs (with the exception of the file server daemon job and the database server daemon job) run in this subsystem. The file server and database server daemon jobs run in the QSERVER subsystem.

QUSRWRK

This subsystem is where the server jobs run for these servers:

Network Print
Remote command and program call
Central
Data Queue
Signon
Database

QSERVER

The file server daemon job, its associated prestart server jobs, and the database server daemon job run in this subsystem.

If this subsystem is not active, requests to establish a connection to the file server or the database server will fail.

Automatically starting subsystems

The QSYSWRK subsystem starts automatically when you IPL, regardless of the value specified for the controlling subsystem.

If you use the default startup program provided with the system, the QSERVER and QUSRWRK subsystems start automatically when you IPL. The system startup program is defined in the QSTRUPPGM system value, and the default value is QSTRUP QSYS.

If you want to change the system startup, you can change the QSTRUPPGM system value to call your own program. You can use the shipped program QSTRUP in QSYS as a base for the start-up program that you create.

Note: If you use the database server or file server and you made changes to the system startup, you must ensure that the startup program starts the QSERVER subsystem.

TCP/IP is automatically started by the system without requiring a change to the system startup program. The host servers are automatically started when TCP/IP is started. The IPL attribute, STRTCP, can force the system to not automatically start TCP/IP at IPL. It is recommended to leave this value at the shipped setting of *YES, (start TCP/IP) but the option is available if necessary.