~~Installing PPC OSX Without CD or Firewire~~
Guide and rant about installing OSX onto a PowerPC based Macintosh without a functioning disc drive or Firewire
This post is for those in the following situation: you’re trying to install Mac OS X onto a Power Mac without a functioning disc drive and perhaps your Power Mac is lacking in Firewire ports or you’re lacking Firewire accessories. Thus, the best way is to install via USB.
Additionally, you've tried the "restore" method with no luck (older version of OSX and targeting an older machine perhaps).
In my case, I was trying to install 10.3 onto my slotloading iMac G3 that lacks both a functioning CD drive and Firewire ports
Note: the solution I found doesn’t necessarily require USB, simply some way of getting the disc image onto the target Mac.
That said though, I’d like to clarify a misconception that I see often on subpar sites such as Reddit or the official Apple forums. Specifically, the idea that “Power Macs can’t boot off USB”. This is categorically false, and anyone who tells you otherwise is merely parroting their ignorance, evidenced by the fact these commentors cannot provide any alternatives or messages of substance.
Power Macs CAN boot off USB; however, it does take some work. A perfect example of this is this guide from the Mac Repository (this guide may prove useful if you need to reinstall Mac OS 9 before progressing).
And here's an old Debian guide that explicitly mentions it.
I will concede that as far as I know only New World ROM Macs can boot from USB; HOWEVER, the only Macs to come with USB out of the box are New World models.
Regardless, if you’re just here for the solution, allow me to quickly tell you what you need to do. Below that, I’ll detail the problem-solving process.
What you’ll need:
· An install of Mac OS 9, divided into at least two appropriately sized HFS+ partitions (one which will hold the installer and the other to be the target). If you need to redo your partition scheme, you’ll likely have to reinstall Mac OS 9. You can refer to the Mac Repository guide I linked above to accomplish that using only USB flash drives.
· Disc image of the target version of OSX you wish to install (in .toast, .dmg or .img so you can mount it in OS 9).
Copy the disc image to your Power Mac (via USB, network share, etc.), then mount it and copy all the contents from the image to the top level of whatever partition isn’t your target (the target cannot also be the source). The source can be the same partition that Mac OS 9 is on, you can have multiple system folders on one partition.
Copying the contents of the disc image to the top-level
of the MacOS9 drive:
Note: some images, when mounted, will automatically open a folder called “Welcome to Mac OS X” or something to that effect. This is not the top-level folder, so close that and open the image icon from the desktop.
You might see something like this when you mount:
You actually want to copy this:
To make the copied OSX installer bootable: go to System/Library/CoreServices and move the file "BootX" onto the Desktop. Close the CoreServices window. Then drag BootX back into CoreServices.
Then go to Start Up items and copied installer should now be detected. Select OSX and if all goes well you should be able to install as normal.
That should be all you need, but what’s with the rigmarole? If you just came for the guide, you can stop here.
~~The Journey~~
As mentioned, my target machine is a slotloading iMac G3 (350MHz, 128MB RAM), and like many slotloaders from this era the disc loading mechanism is basically non-functional at this point. Thus, I looked to install OSX via USB just like I had with OS 9 when I upgraded to an SSD.
Many guides online mentioned that it should be possible to “restore” the disc image onto a USB drive using either Disk Utility or the “asr” command in the terminal. Unfortunately, this mostly didn’t work.
Example:
How to "burn" (or write or clone) a bootable disk image onto an USB stick in Mac OS X using Disk Utility (Mac Repository)
Luckily, Mac OS also comes with the boorish “dd” utility, which also works (for those afraid of Terminal, balenaEtcher does the same thing within a bloated electron app):
How to "burn" (or write or clone) a bootable PowerPC disk image onto an USB stick in Mac OS X using "dd" in Terminal (Mac Repository)
However, while the iMac could pick up on these images, they’d quickly run into the “prohibited” error. Which I later learned with verbose mode (hold ⌘+V at start up) was the Mac stuck at “Still waiting for root device”. Basically, it’d start booting from the USB but loose it somehow and hang.
I tried disc images from several sources, as well as various versions of OS X but they all gave me virtually the same error.
This also happened if I tried booting from OpenFirmware (as one would if they were installing OS9 from USB).
· Boot usb1/disk@1:,\\:tbxi
Or…
1. Devalias ud /pci@f2000000/usb@19/disk@1
2. Boot ud:,\System\Library\CoreServices\BootX
That said, I knew this should be possible, because there was one image that would boot and load the installer app. 10.4 Tiger Modified for G3; however, likely due to my paltry 128MB of RAM the installer would immediately crash if I clicked on anything.
Armed with only determination and nothing better to do, I resolved to find out why the modified 10.4 could boot and no other.
Skimming the Macintosh Garden comments section, the name “xpostfacto” caught my eye. A familiar name to those who play around with vintage Macs. I got it into Mac OS 9 and…. It wouldn’t allow me to select the flash drive as an installer CD because it was “not bootable”. Et tu, xpostfacto?
This was the first time I tried copying the installer files onto one of the internal partitions. When I did that xpostfacto allowed me to select the partition as an installer CD. Nice!
Unfortunately, hitting the “install” button would just reboot into the familiar “prohibited” screen.
It was at this point when I went down the cursed rabbit hole of “blessing” Mac OS system folders.
For those unfamiliar, a Mac System folder must be “blessed” before it can be booted (basically just a flag that says “yes! This folder has what I need to boot!”, very fast summary here). Luckily, Mac OS X contains a Terminal command to bless an OS X volume. Unluckily, it doesn’t work.
I tried on both my M1 Pro MBP and Intel MBP and both would throw various errors no matter the option combo.
I eventually found this command:
· sudo bless –-folder “/Volumes/Mac OS X Install Disk 1/System/Library/CoreServices/” --bootinfo “/Volumes/Mac OS X Install Disk 1/usr/standalone/ppc/bootx.bootinfo”
Unlike the other options I tried (e.g. pointing to the device identifier) this one did not spit out an error, instead it spat out nothing, an improvement.
As expected, prohibited error.
Another option I saw for “blessing” was running Disk First Aid in Mac OS 9, no change (further research seems to indicate this is not a valid method of blessing a System Folder). Prohibited error.
It was at this point I watched this video from Action Retro where he just installs Mac OS 9 with a USB DVD-ROM drive after forgetting to install the CD-ROM drive during reassembly… Come on, that’s literally a USB boot!
At this point, I was fully convinced the error was related to an unblessed system folder. For some reason, in the process of restoring the disk image to the flash drive it must be losing the “blessed” status somehow. Afterall, the installer CD would obviously be blessed and was able to boot via USB. Thus, I dug further into blessing an OS X System Folder, which is where I learned the method of “moving BootX out of CoreServices and then putting it back”. Which did the trick.
Final note: I tried performing the trick with the USB
drive directly (i.e. not copying to an internal partition) with no luck. It
seems there’s still something missing to get a direct USB boot that the 10.4 modifier
figured out that I haven’t.