Admin Alert: Setting Up Unattended i5 Server IPLs

Published: May 24, 2006

by Joe Hertvik

Few i5/OS administrators want to log on to a system in the middle of the night, early Sunday morning, or on a holiday just to IPL that machine for PTF application or to correct a problem. Fortunately, the i5/OS and OS/400 operating systems provide a simple way to automatically power down and power up your system anytime you want, even if you are not signed on to the box.

To review all your IPL options and to set up a schedule for automatically IPLing your machine, there are two places to look on an i5, iSeries, or AS/400 box.

First, you can audit and tweak all of the system values that control how your partition performs an IPL. There are several system values that you can change, and each value controls a different IPL function. IPL system values include the date and time to automatically restart a partition that has been shut down; what type of IPL the system should perform; whether the system can be IPLed from a remote session running over a communications line; and how long the system should wait for running jobs to end before automatically powering down. It is valuable to familiarize yourself with these values, even if you only IPL once a year. You can find out more about each of these functions in a column I wrote last year on how to audit your IPL parameters.

When you need to set up a power off and power on schedule or you want to power off and power up your system from a menu interface, you can go to the green-screen Power On and Off Tasks menu. This menu provides options for immediately performing system power events and for setting up a power off and power on schedule. Automatic power events can be performed on a one-time basis or as part of a weekly schedule; the setup is entirely up to you. I'll focus on these features in the remainder of this article.

You can start the Power On and Off Tasks menu by entering the following Go to Menu command (GO) from a 5250 command line.

GO MENU(POWER)

If you are planning to perform an immediate system power down by using this menu, you may want to enter the menu from the system console so that, if necessary, you can monitor the progress of your power off commands as they are executed.

The Power On and Off Tasks menu contains the following menu options:

1. Display power on and off schedule
2. Change power on and off schedule
3. Power off the system immediately
4. Power off the system immediately and then power on

The first two options allow you to set up and view a schedule for automatically powering down and powering up your partition, while the final two options allow you to immediately power down or restart your system. Here's how each of these options breaks down.

Manually Shutting Down and Restarting a Partition

If you are planning on totally shutting down your system for a limited amount of time to perform hardware maintenance, you can use option 3, Power off the system immediately. When you select option 3, the system displays a screen showing the next time (if any) that the system will automatically power up again after it powers off. If you select option 3 in error, you can back out from ending the system by pressing F12=Cancel. The system will also require you to confirm that you actually want to power down the system by pressing F16=confirm immediate power off.

Selecting option 3 is the equivalent of running the following Power Down System command (PWRDWNSYS).

PWRDWNSYS OPTION(*CNTRLD) RESTART(*NO)

After running option 3, the system will immediately shut down without restarting. You can restart the system by manually performing an IPL; it can also be restarted automatically if you set up a date and time for the system to automatically restart in the QIPLDATTIM system value (Date and time to automatically IPL) or in the system's Power On/Off schedule.

If you want to manually shut down the partition and then immediately start it up again, you can select option 4, Power off the system immediately and then power on. This option is the equivalent of performing the following PWRDWNSYS command.

PWRDWNSYS OPTION(*CNTRLD) RESTART(*YES)

This option is most often used when applying PTFs to your partition.

Scheduling Power Off and Power On

As opposed to options 3 and 4, which are used to manually shut down and restart the system. option 2, Change power on and power off schedule, is used to set up a schedule for automatically performing the same functions.

Selecting option 2 displays the Change Power On/Off Schedule screen, which presents an editable list of upcoming dates where you can enter times for when the system should automatically power down or automatically power back up. On this screen, you can enter one set of power on/power off times for each date along with a description for why you are stopping and restarting the system on that date. But be careful of the following restrictions on setting up scheduled power events on this screen.

• For any specific date, the time for automatically powering off your partition cannot occur within 30 minutes of the time that the system will be powered back on again. The presumed intent here is to give the system enough time to complete the first power off/power on function before attempting to run its opposite function. However, the default value for the Controlled End Delay Time parameter on the PWRDWNSYS command (which designates the amount of time the system will wait for all jobs to end before automatically powering down) is 3600 seconds, or one hour. So to avoid any possible problems with these functions overlapping each other, you might want to make sure that there is at least an hour between any power on and power off times that you enter for a specific date.
• You cannot enter a power off or power on entry for a time and date that has already passed.
• Since you can schedule several dates in the future for power events, i5/OS will take the earliest power on date and time in the schedule and use it as the values for the QIPLDATTIM system value (the date and time to automatically IPL the system). As that date and time pass, it will replace those values in QIPLDATTIM with the values from the next earliest power event, if one is available.
• If you enter a time and a date for the system to power on and the system is not powered off when that time arrives, no action will be taken.
• By default, the system will send a warning message to all users 30 minutes before a scheduled power off event that the system is scheduled to be powered off in a half hour. It will also send an inquiry message to the QSYSOPR message queue 10 minutes before a scheduled power off event asking the operator if he wants to cancel the operation.
• If you schedule a power off event on an i5/OS or OS/400 partition that is the primary partition for an AS/400, iSeries, or i5 system, the power off event may also trigger all the secondary partitions to power off. So be careful when using this schedule on a primary partition.

You can also use option 2 to set up a weekly schedule for powering off and powering up your system. You can do this pressing the F10 key from the Change Power On/Off Schedule screen to get to the Change Power On/Off Defaults screen. On this screen, you can schedule reoccurring power off and power on times by the day of the week. Once you enter a weekly schedule for restarting your system and press Enter, option 2 will adjust all the future entries that occur on that day of the week to power the system off and power it back on again at the default specified times. If you want to override, or turn off, one of the scheduled times, simply go to the Change Power On/Off schedule screen and blank out or change that time on the scheduled date.

Finally, to view the power off and power on schedule for your partition, you can select option 1 off the Power On and Off Tasks menu, Display power on and off schedule. Here you can simply look at the schedule without any danger of accidentally changing a schedule power event.

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A Quick Audit of Your IPL Parameters