Hello!
I did not know where to post my experience … because it is between hardware and software. You will understand what I mean …
So, few weeks ago, I got my hands on an official CD to restore a Macintosh Server G4 with … MacOS X Server 1.2 (Rhapsody …).
My main goal is to try to use it on a Mac Mini G4 but this would imply to erase completly the content of my internal drive and I prefer to find another solution.
I also have official CDs to install directly Rhapsody but this was funky to try this …
So what I did is:
- On my MacBook Pro using High Sierra:
- put the CD in my drive to copy the ASR image on my internal disk
- use Disk Utility to "convert" the ASR image to "master CD/DVD" format
- insert my microSD card in my MBP
- copy the converted image on my microSD card and renamed it to HD60_512.hda (I already have some others hda on it)
- On my PowerMac 6100 which use a BlueSCSI to boot:
- insert my SD card in the BlueSCSI
- boot my 6100 as usually on its most stable partition which contains a 7.5.3
Tadaaaaa!
The Macintosh Server G4 partitions appears on 7.5.3.
As I expected, the ASR image contains exactly a sort of "dd" imaged hard drive with its Apple SCSI drivers and so on.
Ok … it is a 7.5.3 and these partitions are using HFS+ and UFS so, there are almost unreadable but I have the well known txt file which explains where my files are gone.
So in a next step, I should be able to try to replicate only the partitions on my internal drive without erasing all the drive.

I know that none of that is related to OS 9 but ASR is often used here to create installations for unsupported mac so …