Starting the system without making configuration changes (unattended IPL)
This is the most common way to start the system. Unattended initial program loads (IPLs) reset system storage and recognize any configuration changes automatically.
Prerequisites
This procedure assumes that the system is running, and requires that several additional conditions be met before you begin an IPL. While most of these settings are the default values, verify them if you are unsure.
- The IPL mode for the system must be set to Normal (unattended IPL).
- The Type of restart (QIPLTYPE) system value must be set to unattended (0).
- Turn on any devices, such as display stations, printers, tape devices, and controllers that you or others want to use.
Situation
Unattended IPLs reset system storage and recognize any configuration changes automatically. The amount of time required for any IPL depends on the size and complexity of the system, ranging from a few minutes to several hours. When the unattended IPL is complete, the sign-on display appears on the display station.
If you are working on a system that has logical partitions, you need to understand how to restart and turn off the system with logical partitions.
Performing an unattended IPL
Enter different options on the command line to perform an unattended IPL.
- Type ENDSYS or ENDSBS *ALL on any command line and press Enter.
More options are available for the End System (ENDSYS) and the End Subsystem (ENDSBS) commands, for example, to set delay time.
- Type WRKSBS to verify that the controlling subsystems have ended and are in the restricted state. The subsystems status must be RSTD.
- Type PWRDWNSYS *IMMED RESTART(*YES) on any command line and press Enter.
When the unattended IPL is done, the sign-on display appears on the display station.
Parent topic:
Starting the systemRelated concepts
Operating mode of an IPL System values that control IPL Subsystems Scheduling a system shutdown and restart