How to get data off a G4 mini with a failing hard drive.

Question

For the record, here's how I ended up solving the problem - I had to invent this combination of approaches and it's not documented on any Web postings I could Google up during a week of working on this:
Situation: Your G4 mini's hard drive dies (unbootable), AppleJack was unable to fix it, and DiskWarrior 4 can't rebuild it and actually crashes before it reaches its Preview stage.
Why is this situation such a puzzle?
* When booted in single user mode, the Mini does not recognize an attached Mac in Target mode, so you can't copy your files to there.
* diskutil can't help you find any attached FW drives since diskutil is unavailable (because sh /etc/rc fails due to disk hardware errors). Even though mount is available, all possible guesses of the attached FW partition name fail ("disk2s2" through "disk7s4" all fail), despite previously confirming what the FW drive or target-mode Mac's partition name looks like to other working Macs.
* Attaching a USB hard drive fails because the USB drivers fail to load, again presumably due to disk hardware errors.
* Booting from OS 10.4 (Tiger) Install DVD doesn't help, because even when running Terminal from the Install DVD, an attached Target-mode Mac is not recognized (diskutil shows no attached devices), and since the 10.4 Install DVD does not include mount_fat32, it's also not possible to mount an attached USB drive.
* Solution! *
Use an OS 10.5 (Leopard) Install DVD to boot the G4 mini. Even though the DVD reports that the old mini is incompatible with Leopard, go ahead and accept that result, and then you can run 10.5 Terminal from the DVD on your G4 mini. Unlike 10.4 Install DVD, this one includes drivers to recognize and mount an attached USB drive, even FAT32 (Windows) formatted drives. So now, in Terminal, you can copy files from your dead hard drive to the USB drive. Whew!
Note: This solution is possible and probably generally useful to people since if you have a dead G4 mini on Tiger, you probably do what I do and go buy a replacement new Mini, which of course comes with a Leopard Install DVD. And generic USB drives are easy to borrow or cheap to buy or you already have one.
Message was edited by: alanngnet

Answer 1

P.s. Additional details that might be helpful to people:
- When you boot Leopard on your old Mini, click "Ok" when it tells you it's incompatible. Then Terminal will be a menu option under "Tools."
- You'll need to have familiarized yourself with basic Unix file commands (practice on another Mac first, for example). If your hard drive is dying, time is of the essence, so learn your commands before you start up your dead Mini.
- Tip for Unix newbies: The crucial commands you'll need are ls and cp. http://www.ss64.com/osx/ is a handy reference manual.
- Hopefully when you run "ls /Volumes" you'll see your mini's dead hard drive listed there as "Macintosh HD" (or whatever you may have previously renamed it). If it's not listed there, you're really hosed. But try again later, maybe when it's as cool (temperature) as possible.
- The destination path for your USB drive is also viewable with "ls /Volumes", e.g. in my case it turned out to be "/Volumes/Elements" (where Elements was the brand name of the drive).
- Don't use dd or ditto en masse because the hardware errors on your drive will screw things up. Instead selectively pick out the files you really need to recover and cp them. Be sure to use -p option to preserve file date/time. I used a lot of "cp -Rpv oldminifolder /Volumes/MyUSBDrive" to copy all contents and subfolders from folder "oldminifolder" to my USB drive. It will also be helpful to use "ls -trl" to see the chronologically most-recently-modified files on your old mini so you pick out which files to copy (e.g., files newer than your most recent backup).
Hope this helps, and thanks to the many other posters out there on the Web who taught me many Unix tricks this week.