Operating mode of an IPL

The operating mode determines the number of options that are presented to the operator for consideration during and after the initial program load (IPL). It can also secure (lock) the control panel to prevent an unauthorized or inadvertent IPL from the control panel.

There are four operating modes:

Normal (unattended)

After the power-on, operating the system in Normal (unattended) mode requires no operator intervention during the IPL.

When you turn on the system in normal mode, it performs the IPL and presents the Sign On display on all available display stations. The operator cannot change the system during the IPL. Dedicated service tools (DST) and the operating system do not present any displays during this IPL.

Use a normal mode (unattended) IPL to perform the following actions:

• Perform an IPL and run the system for most routine work
• Perform a remote IPL
• Turn on and perform an IPL by date and time

Manual (attended)

After power-on, operating the system in Manual (attended) mode means that an operator uses the control panel to direct the system for special needs.

During manual mode IPL, DST and the operating system present menus and prompts that allow you to make changes to the internal system environment. This can include entering debug mode for service representatives to diagnose difficult problems.

Use the manual mode to perform an IPL and run the system to perform the following actions:

• Change IPL options (including system values)
• Install the operating system
• Load fixes (PTFs)
• Make some types of system hardware upgrades
• Use DST (for advanced users and service only)
• Problem diagnosis (for advanced users and service only)

Auto (automatic)

Use Auto mode for an automatic remote IPL, automatic IPL by date and time, and an automatic IPL after a power failure.

Secure

Use Secure mode to prevent use of the control panel to perform an IPL. This mode is not a form of IPL; it is a means to prevent an unauthorized or inadvertent IPL from the control panel.