Target Disk Mode - can’t see all the drives

[wayneh69]

Hi

I have a PowerMac MDD with 1.25 DP (FW400), and a white MacBook core duo 2.0 with FW400 port.

The PowerMac had three physical drives (2xOWC SDDs and a spinning hard drive) which boot into os 9.2.2; Leopard and Tiger.

My issue is: when restarting in target disk mode on the MDD, with the Macbook connected via firewire, I ca only see the OS 9 disk and not the other two from the Macbook. Shouldn’t I see all three dives?

[peeperpc]

Are the two drives connected to a PCI SATA card?

IME, only drives connected to the Mac's native ATA bus(es) show up in FireWire Target Disk Mode on another Mac.

[wayneh69]

Thanks - for the respose.

All three drives are connected to the ATA bus (2 rear and 1 front). The one showing up is a OWC branded 120 SDD, which is exactly the same as one of the other drives. The spinning HD in the front bay is a seagate barracuda.


Wayne

[DieHard]

All three drives are connected to the ATA bus (2 rear and 1 front)

Just as a test move an additional drive from the "front" to the "rear" ATA.  It may be that only the primary ATA bus is seen.  Never noticed this, after all these years, but I usually only use target mode on machines that are harder to open... iMacs, laptops, etc.  You may have discovered something.

[joevt]

Should be able to find the answer by looking at Open Firmware dumps.
 https://forums.macrumors.com/threads/question-how-powerful-of-a-graphics-card-will-work-in-a-beige-power-macintosh-g3.2303689/post-30082400

I don't have a G4 MDD to test. The following is what I could decipher from looking at the init? word of the firewire-disk-mode package in my "ROM PowerPC Mac/ROM G4 Mirrored Drive Doors/Dump/Part2.of" file.

In Open Firmware, what's the value of product-family?

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product-family

If it's 2 or 4 then the default list of supported devices is:

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cd:0,cd1:0,zip:0,ultra3:0,ultra2:0,ultra1:0,hd:0

Otherwise, the default list of supported devices is:

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cd:0,hd:0

Check devalias for the full path of each of those.

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devalias

Are all your disks matching one of those paths? I think you can use the dir command to list the files on each one but that requires knowing the partition number of an HFS, HFS+, or FAT file system. I have a list-partitions command but you need to connect using telnet or serial port to paste it in.

If you know where your disk is, and it's not one of the above paths, and it's readable in Open Firmware maybe you can add it to the path list.

Does aapl,tdm-units appear in the options device or printenv result?

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dev options
.properties
printenv
It's probably an empty string which means it will use one of the default lists above.

If the disk you want to add is mydisk:0 then you would add it like this:

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setenv aapl,tdm-units cd:0,cd1:0,zip:0,ultra3:0,ultra2:0,ultra1:0,hd:0,mydisk:0

Verify that the change appears in the options device

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dev options
.properties

After making the change, restart and try target disk mode again.

The maximum number of drives target disk mode will support is max-units which is 6. This can be patched but most people don't have that many disks.

[GaryN]

Hi

I have a PowerMac MDD with 1.25 DP (FW400), and a white MacBook core duo 2.0 with FW400 port.

The PowerMac had three physical drives (2xOWC SDDs and a spinning hard drive) which boot into os 9.2.2; Leopard and Tiger.

My issue is: when restarting in target disk mode on the MDD, with the Macbook connected via firewire, I ca only see the OS 9 disk and not the other two from the Macbook. Shouldn’t I see all three dives?

I want to make sure I understand this because it doesn't make sense to me.

You say you are trying to boot your Macbook via target mode from drives in your MDD?
Aside from asking the obvious question… why? There are a couple of caveats to be considered.

Assuming for a second that all drives in the MDD are visible to the MB, we ask: Why wouldn't Tiger or Leopard show up?
The first thing I can think of is that we must remember that both the later versions of Tiger and all versions of Leopard were packaged as both PPC AND Intel compatible. The installer in both would first look at what machine it was launched on then install the proper files for that machine.

That means if they were installed on a PPC machine, they won't boot an Intel and vice-versa.

So, why would the OS9 System show up at all since it certainly won't boot the Intel either? I have NO idea. Maybe there's some odd characteristic about it (the MDD Multiprocessing file?) that is basically unknown since virtually NObody would even try that anyway.

To resolve the "Is it the SSD or the ATA bus or the ghost of Jobs" question you need to boot the MacBook from it own OS then start the MDD in TD mode to see if all 3 drives show up.
If they DO, the above is likely correct.
If they DON'T, maybe it IS a "Where and on which ATA are they all?

OR… more likely:

You didn't specify, but I'm guessing that OS9 is on the spinner and Tiger and Leopard are on the SSD's.
That would mean the ATA adapters or whatever you're using to connect the SSD's causes them to not show up in Target Mode.

OR, going back to my first sentence, am I misunderstanding what you're even trying to do in the first place?

[joevt]

This is my understanding:
The MDD has the three drives.
The Mac being restarted in Target Disk Mode is the MDD.
The MacBook is not being restarted. It is connected to the MDD so that when the MDD enters Target disk Mode, the MDD's disks should appear in the Finder of the MacBook.

The MacBook is a Core Duo 2.0 so it must be running Mac OS X. Which version? If a disk doesn't appear in the Finder, does it appear in the diskutil command? The mount command?

Code: [Select]

diskutil list
mount


[GaryN]

OK…… So most of what I wrote above… per Rosanne Rosannadanna: "never mind".
Going with: MacBook booted first then MDD booted in Target Mode. I did an experiment:

I have a MacBook Pro running Catalina.
I also have an MDD with 6 volumes on FOUR drives:
ATA100 rear: Leopard;  OS9.2.2 & Aux files
ATA66 front: TM backup; Archive files & OS9.2.2 for emergencies

So, When I boot the MDD in Target Mode, ONLY OSX Leopard comes up on my MBP.
Note my OSX is on an SSD with a Red Startech adapter in the Master position of the ATA100 bus although all drives are set to Cable Select.

I've never had to try this before but since both of our similar setups seem to show only one drive, I'm now suspecting it may be normal.
Especially if your OS9 is also in the front position on the rear ATA100 bus. That may be the default "primary drive" position where Target Mode looks first.
They go in order
Disk 0: ATA100 master
Disk 1: ATA100 slave
Disk 2: ATA66 master
Disk 4: ATA66 slave

I'm not curious enough to dig into my MDD and start swapping drives around but you might want to see if whichever drive you put into the Disk 0 position is the only one that comes up on the MacBook.

If you must have all MDD drives available on the MacBook, you can always connect them over Ethernet either directly or thru your router.

[joevt]

I'm not curious enough to dig into my MDD and start swapping drives around but you might want to see if whichever drive you put into the Disk 0 position is the only one that comes up on the MacBook.

Are you curious enough to follow my Open Firmware instructions?

[GaryN]

Are you curious enough to follow my Open Firmware instructions?

Actually, no. This was / is not my problem to begin with. I've already spent quite a bit of time on it already.

[wayneh69]

Thanks for the replies everyone - and taking the time to think about this issue.

The spinning drive in the front bay has Tiger on it. The rear drives have Leopard and OS 9. I use OS 9 to run Rebirth RB 338 and Leopard to run (Propellerheads) Recycle and Reason 4. The spinning HD is big so has a stash of samples and loops that I wanted to transfer to the Macbook (Leopard 10.5. which also has Reason 4 on it. I’m away for a week and wanted to take the Macbook to do learn some more of the Reason workflow and thought that it would be handy a quick to use TDM, neber having used it before - ofcourse I could and did in the end use a USB stick - but it bothered me that I could onle see the one drive so thought I’d ask the community…!

I will certainly try some of the suggestions and I wonder if it has anything to so with the IDE/ATA adpaters and the master/slave settings? I’m not sure what the settings are but will have a look when I get back next week.

Thanks so much for giviing some thought to this issue!

[ssp3]

What does the MDD Developer Note says about the Target Disk Mode?

[wayneh69]

Target Disk Mode

The user has the option at boot time to put the computer into a mode of operation called Target Disk Mode (TDM). When the Power Mac G4 computer is in Target Disk Mode and connected to another Macintosh computer by a FireWire cable, the Power Mac G4 operates like a FireWire mass storage device with the SBP-2 (Serial Bus Protocol) standard. Target Disk Mode has two primary uses:

■ high-speed data transfer between computers

■ diagnosis and repair of a corrupted internal hard drive

The Power Mac G4 computer can operate in Target Disk Mode as long as the other computer has a FireWire port and either Mac OS X (any version) or Mac OS 9 with FireWire software version 2.3.3 or later.

To put the Power Mac G4 computer into Target Disk Mode, restart the computer and hold down the T key until the FireWire icon appears on the display. Then connect a FireWire cable from the Power Mac G4 to the other computer. When the other computer completes the FireWire connection, a hard disk icon appears on its desktop.

If you disconnect the FireWire cable or turn off the Power Mac G4 computer while in Target Disk Mode, an alert appears on the other computer.

To take the Power Mac G4 out of Target Disk Mode, drag the hard disk icon on the other computer to the trash, then press the power button on the Power Mac G4 computer.

For more information about Target Disk Mode, see the section “Target Mode” in Tech Note 1189, The Monster Disk Driver technical note. For information about obtaining the Tech Note, see “Apple Technical Notes” (page 65).

[wayneh69]

The technical note does not seem to help on this point either from what I can make out.

 

[ssp3]

Try 'diskutil list' in Terminal, as joevt suggested.

[peeperpc]

I tried it with my FW400 MDD. Only the master drive on ATA100 showed up, the slave didn't. I have no drive connected to other ATA buses, except for the optical drive. So couldn't test that.

BTW, I found someone said, for PPC Macs prior to 2003, only the master drive on the first ATA bus is available through target mode. The Macs came after that have all drives accessible.
https://uk.comp.sys.mac.narkive.com/fCYeDE92/target-disk-mode-ppc-and-intel

[DieHard]

BTW, I found someone said, for PPC Macs prior to 2003, only the master drive on the first ATA bus is available through target mode. The Macs came after that have all drives accessible.

So that pretty much means we are at the end of the line for PPC machines that can natively boot to OS9

This is very interesting because I am shocked I never noticed this, but it kinda makes sense that I didn't because target mode is my "go-to" for things like iMacs with broken screens, laptops with broken screens, etc., and these machines have only 1 internal drive;  normally with towers I just open the door, swap drives, copy and clone... still this is one of those quirky mac scenarios.  It is amazing to think Apple did something without really documenting it... LMAO

"Think Different, Design different, and remember to keep the user guessing..."

[joevt]

You can try accessing the disk from Open Firmware. And if that works, then add the disk to the aapl,tdm-units nvram property.

[joevt]

If the disk is visible when you hold the Option key at boot (must have a bootable partition on the disk), then it means it's accessible from Open Firmware.

[GaryN]

Arrgh……The……Thread……That……Won't……Die !!!

BTW, I found someone said, for PPC Macs prior to 2003, only the master drive on the first ATA bus is available through target mode. The Macs came after that have all drives accessible.
https://uk.comp.sys.mac.narkive.com/fCYeDE92/target-disk-mode-ppc-and-intel

That was one unverified quote from one guy in the UK 15 years ago…
Even if true, it would be of very limited use around here… Anybody have a G5 or a pre-Catalina Intel radiator or trashcan to test?
I would imagine you would need be running OSX to see much of anything beyond the G5.

You can try accessing the disk from Open Firmware. And if that works, then add the disk to the aapl,tdm-units nvram property.

If the disk is visible when you hold the Option key at boot (must have a bootable partition on the disk), then it means it's accessible from Open Firmware.

Everyone who's ever booted a Mac in Target Mode must have noticed that it comes up in just a second or two.
That is because a subroutine is invoked that provides an interface to and mounts the drive on the FW bus - a place the drive would never see normally. It doesn't even bother to send over the drive's icon - only a generic icon or no icon at all appears on the receiving end.

I suspect that makes all of the above Open Firmware ideas moot because the Target machine never really even loads the OS. It just connects the drive and displays the FW symbol onscreen.