I’m sure the logic to end subsystems before issuing the PWRDWNSYS command is correct and good advice. But if issuing the ENDSBS command does not shutdown the (especially considering the message I received via command line and prompted entry) subsystems in correct order, one could still use one or two commands to list subsystems, but if you don’t know which should (or correct sequence of subsystems to shutdown in order) be shutdown, you could / would still end up with an abnormal shutdown, or could do more damage than issuing the PWRDWNSYS command, where if cache/data loss problems arise as mentioned earlier in this dialogue.

the front panel LCD for a manual could show 01 BM (I believe this is the manual-attended IPL mode).
If an automatic IPL is selected (there are buttons on front to page/scroll thru the options, along with entere button and power button) it likely will show

01 BN in the display (as long as power connected and AS/400 running or shutdown) is likely an automatic IPL. If in automatic IPL all you should have to do is push the power button in (exception would be if system value in some options were changed to auto IPL after power restored, or shutdown and immediate IPL are specified in system options/config.) and the system will IPL without operator/QSECOFR intervention. If your system does not show 01 BN (or some other possible changed code or alternate code) for automatic IPL, from OS/400 V4R2 and later you have to enter a system password (if in auto IPL mode this likely has already been done so you don’t have to enter it). You can IPL without a system password for about 70 days, after which if you don’t have a system password, the machine will no longer IPL.

To shutdown the system:

PWRDWNSYS *CNTLD (may take some time to shutdown depending on workload/subsystems etc
– OR – PWRDWNSYS *IMMED (immediate shutdown) is not instantaneous but takes about 10-15 minutes.

ENDSBS (*ALL) may be a better choice before entering the desired PWRDWNSYS. But I read somewhere that if certain subsystems are not allowed to complete processing an abnormal shutdown could ensue, and that would require a longer IPL while the system recovers from the abnormal shutdown.

I contemplated setting the system config/value to auto IPL on power restoration, but after thinking, if you have a storm, water leak, fire, etc, where automatically bringing the machine up after short or prolonged loss of power may not be wise (water dripping on your machine will not extend its life… and will surely fry it once water and electricity mix).

A manual IPL requires (mode has to be chosen on front panel for the various modes) you (OS/400 V4R2 and later) to enter a system password, new unique system identifier, proceed thru some other requirements and options and eventually select to IPL. You’ll be prompted each step of the way.

You can find good info online at IBM’ AS/400//iSeries web online resource “boulder co. site”
Also the book: The As/400 Owner’s Manual for V4 by Mike Dawson (MC Press) is a good reference (not completely exhaustive and dealing with all detail, some chapters refer to IBM manuals.

You use the restart *YES only if you are going to restart immediately.

You should be aware that the OS has options for scheduled power off and on. If you use the scheduled power off, plan your operations around shutting down jobs beforehand to reduce the chance of any issues.