There are people that tried, it doesn't work. There's something proprietary written at low level that gets erased doing a low level format ( required to change the sectors ). The specifics were never released... With this I mean that the trick is not the firmware of the disk, but low level bits on the platters
About the automatic shutdowns/restarts , I agree but I think it's a feature that was mainly directed at smaller AS used in satellite offices to support the local workforce and that had nothing going on, as a consequence, outside of business hours -----Original Message----- From: cctalk <cctalk-boun...@classiccmp.org> On Behalf Of Patrik Schindler via cctalk Sent: Wednesday, January 6, 2021 2:22 PM To: General Discussion: On-Topic and Off-Topic Posts <cctalk@classiccmp.org> Subject: Re: DEDICATED HOBBYIST ALERT: IBM AS/400 9406-F2 for cheap sale in Germany Hello, Am 06.01.2021 um 13:37 schrieb mazzi...@tin.it: >> What I understood from your last posting is that once you reformat an AS/400 >> disk for 512 Bytes per sector as used by commodity hardware, you can’t use >> it again on AS/400, even by reformatting. > > Yes, that's correct Hm, I never verified that claim. Maybe I once had such an ex-AS/400 disk in earlier times which might sit unrecognized in my hard disk drawer. I can’t confirm your claim but I doubt it’s true: Firmware extensions will not get overridden from a reformat, and you can always reformat with 522 Bytes/Sector. I bet it will work again. > And I doubt that there's an orderly shutdown from the panel… That’s exactly what I wanted to express. :-) > I remember being told of only one procedure, but it would not cause > damages/issues of sort. I’ve read about that procedure in an IBM (red)book and it’s „not recommended for regular use“. I would need to look up the source if you want a proof. > In any case we're speaking about something that was meant to be turned on and > never turned off unless some maintenance or a big issue. The OS has highly sophisticated scheduling for automatic start and shutdown, with possible exceptions per weekday and one-time exceptions like holidays. (Type GO POWER into the command line to see the menu.) I guess even one or two decades back, there was reason to save power. > and for a catastrophe where the terminal is not accessible That’s what I mean. The procedure is not meant to be used as a substitute for pwrdwnsys. :wq! PoC