Boot G5 From USB?

AmazingHenry

macrumors 65816
Original poster
Jul 6, 2015
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Central Michigan
Was trying to boot my G5 from a USB flash drive earlier today. Plugged in the flash drive, booted into Open Firmware, and typed this:
Code:
boot ud:,\\:tbxi
Unfortunately I got a prohibited sign.

This method works perfectly for my Mac mini G4, iBook G4, and iMac G4. However I could never get it working with my G5. Is there a way to boot a G5 from USB?

Thanks,
Henry
 

foxlet

macrumors 6502
Aug 5, 2016
277
392
Usually for booting flash media, it's a better idea to execute BootX directly, such as with
boot ud:3,\System\Library\CoreServices\BootX
(assuming ud points to the proper USB device, and the OS X filesystem is on the third partition), but it seems more like you're trying to run a copy of OS X that isn't compatible with that specific platform (maybe it's too old?) or is crashing early on in the kernel loading process.
 
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AmazingHenry

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Original poster
Jul 6, 2015
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Central Michigan
No, I'm running a 10.5.4 Leopard installer on a 2.0GHz DP G5, so it's not incompatible... I'll be sure to try that command soon, however.
 

AmazingHenry

macrumors 65816
Original poster
Jul 6, 2015
1,285
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Central Michigan
Sorry that I haven't given you an update lately. :(

Anyway, I tried your command, @foxlet, but I get the same prohibited sign. Well, I settled for using TDM in the end anyway, so it doesn't matter anymore.
 

MacCubed

macrumors 68000
Apr 26, 2014
1,618
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Florida
Certain G5's lack the ud alias, and thus, making that command not work. I know the 11,2 G5s work fine booting from USB (through this command and the boot devices menu), but my 7,2 did not work properly. I ended up cloning the install to a 2.5" SATA HDD, and booting off of that. This was the first video I made on my YouTube channel, outlining the process, if anyone is interested.

 
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foxlet

macrumors 6502
Aug 5, 2016
277
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You can manually reassign the ud alias to a new device, hence the idea to check it. Anyways, in this situation it would be better to use verbose mode in order to get a more useful output.
 

foxlet

macrumors 6502
Aug 5, 2016
277
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How would I do this?
In the OpenFirmware session, use dev / ls to show all the existing paths for the system, then devalias ud to set ud to the proper path, for example: devalias ud /ht/pci@2/usb@b/disk@1

Alternatively, you can replace ud with the direct path.
boot /ht/pci@2/usb@b/disk@1:2,\\:tbxi
 

MrRPI

macrumors newbie
Mar 3, 2018
5
1
Usually for booting flash media, it's a better idea to execute BootX directly, such as with
boot ud:3,\System\Library\CoreServices\BootX
(assuming ud points to the proper USB device, and the OS X filesystem is on the third partition), but it seems more like you're trying to run a copy of OS X that isn't compatible with that specific platform (maybe it's too old?) or is crashing early on in the kernel loading process.
@foxlet I'm so happy that your solution finally worked that when it worked I almost wet myself.

Thank you @foxlet
 
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reukiodo

macrumors 6502
Nov 22, 2013
294
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Earth
Am I the only one who has never had any issue booting any Mac to OS X from it's built-in USB ports? All I use is the Alt/Option on boot and it shows the USB drive... I have even booted the first-gen iBook this way, since it has no FireWire ports...
 

Fami7455

macrumors member
Jul 6, 2019
38
66
The computer (The network)
PowerPC Macs are really strange when it comes to USB booting. I've had G5s which wouldn't boot unless I used @foxlet 's method; I've had an MDD and a FW800 which booted from an NEC PCI USB2.0 controller without issues, even showing the drives in the boot picker; and everything in between. Apple's implementation of OpenFirmware is a tad cobbled together compared to, say, Sun's.
 

bunnspecial

macrumors 604
May 3, 2014
7,259
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Kentucky
Most AGP-based PPC Macs with USB 1.1 will USB boot without any trouble or any special tricks. Just stick in a bootable USB disk, load the boot picker by holding Option, and the USB disk will show as a bootable option there. In fact, this was even an advertised feature when the Sawtooth was released.

As Apple transitioned to USB 2.0 with the G5 tower/later iMac G4s/aluminum PowerBooks/iBook G4s, booting from USB got increasingly more difficult. On a LOT of these, "boot ud:,\\:tbxi" from OF will work fine, but as this thread shows not always. I ran into it myself a while back when I was trying to install Leo server on an Xserve G5(the Xserve shipped with CD-RW drive, while Leo server was always on DVD). I finally ended up doing a TDM install from a PowerBook, and later installed a DVD-RW from a parts PowerBook.
 
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swamprock

macrumors 6502a
Aug 2, 2015
977
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Michigan
Most AGP-based PPC Macs with USB 1.1 will USB boot without any trouble or any special tricks. Just stick in a bootable USB disk, load the boot picker by holding Option, and the USB disk will show as a bootable option there. In fact, this was even an advertised feature when the Sawtooth was released.

As Apple transitioned to USB 2.0 with the G5 tower/later iMac G4s/aluminum PowerBooks/iBook G4s, booting from USB got increasingly more difficult. On a LOT of these, "boot ud:,\\:tbxi" from OF will work fine, but as this thread shows not always. I ran into it myself a while back when I was trying to install Leo server on an Xserve G5(the Xserve shipped with CD-RW drive, while Leo server was always on DVD). I finally ended up doing a TDM install from a PowerBook, and later installed a DVD-RW from a parts PowerBook.
I have one G5 that refuses to boot from USB, and that's the 7,3. Every other AGP machine, and my DC G5, finds and boots from USB just fine, but not that one. It also hates Linux for some odd reason, no matter what video card, RAM, or storage I put into it. A quirky beast...

I wonder if your Xserve is based on the same hardware as my 7,3...?
 

Jubadub

macrumors regular
Nov 1, 2017
198
232
I can boot from USB on a Mac mini G4, which has USB 2.0, even without OF, but I only tested it with OS 9. It may or may not be relevant to know that, despite the mini being equipped with USB 2.0, booting OS 9 occurs with 1.1 (1.0?) speeds, because of lack of USB 2.0 drivers for OS 9.
 

sobrazz

macrumors newbie
May 4, 2020
4
0
hi! can someone , please help me to load Mac OS on powermac G5 with an empty harddisk? I tried usb drive and somehow I cannot boot it up when I hold option key. please help this old machine to see lights again. thank you
 

Macbookprodude

macrumors 65816
Jan 1, 2018
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ЗША
I have had no issues at all booting PPC machines from USB. What MacOS are you installing ? Leopard or Tiger, or PPC Snow Leopard ? You would use USB boot command under OF: boot ud:,\\:tbxi
 

eddjones99

macrumors newbie
Jun 25, 2020
2
0
hi im new here , im having the same problem as the guys who just cant get usb boot to work on powerpc G5 Tower dual 2g version. I have tried everything on here and some attempts from other forums still no boot. If i post a picture of my firmware screen can someone show me which entry is my usb stick, mac os says it should be disk1s3 but i cant find ant reference to that reading through the list. If someone could look thru my firmware and work out what i need to type to get usb to boot im trying to install leopard server on it. i have it on usb but cant get it recognised , ive tried creating using GUID and also Apple partition map.thnx in advance.
 

alex_free

macrumors 6502
Feb 24, 2020
307
592
hi im new here , im having the same problem as the guys who just cant get usb boot to work on powerpc G5 Tower dual 2g version. I have tried everything on here and some attempts from other forums still no boot. If i post a picture of my firmware screen can someone show me which entry is my usb stick, mac os says it should be disk1s3 but i cant find ant reference to that reading through the list. If someone could look thru my firmware and work out what i need to type to get usb to boot im trying to install leopard server on it. i have it on usb but cant get it recognised , ive tried creating using GUID and also Apple partition map.thnx in advance.
I have never gotten usb booting to work on any of my PPC macs, just my 2 cents.
 

mortlocli

macrumors member
Feb 23, 2020
49
21
z970 ..when you say you have a copy of Fienix on the usb stick..is that simply a copy of the .img file?
 

z970mp

macrumors 68040
Jun 2, 2017
3,047
3,053
The Matrix
@mortlocli Not merely transferred standalone. The .img file will need to be restored to the stick preferably by either Etcher or dd in order to be bootable by Open Firmware.
 
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