How can I rescue my files from my iBook in single user mode?

October 7, 2005 5:35 PM

How can I rescue files from my iBook in single user mode? Or mount it on my G4 desktop without causing that to crash?

The file system on my iBook is hosed*. I can't boot from either the hard disk or the System install discs that came with it. If I boot in Firewire Target Disk mode and plug it into my desktop G4, the latter becomes unresponsive and needs a forced reboot. I think that's all the obvious approaches used up.

I can, however, boot into single-user mode. fsck won't help me - it says 'keys out of order'. I can see all the lovely lovely files I want back. But if I do 'mount -uw /' to try to make a mount point for an external drive, it all freezes up.

Is there a way I can get copies of my files whilst leaving the disk in a read-only mode like when you first boot in single-user? Ideally, is there a way to use the iBook in Target Disk mode and mount it read-only on my G4?

Would a sensible approach be to download a Linux CD and boot from that? Would it be possible to then mount the internal drive read-only and an external firewire drive to copy to?

I am less knowledgeable about this Unixy stuff than my casual use of jargon may suggest.

*probably of no help at all, but the problem may be related to this: /Volumes contains 'Macintosh HD' as expected, and also

posted by nowonmai to Computers & Internet (11 answers total)

Use a firewire cable to connect the iBook to the G4 desktop, and hold down the T button while the iBook boots up. It should mount the hard drive automatically.

Here's more info. It's called Target Disk Mode.
posted by spiderskull at 5:56 PM on October 7, 2005

Uh, I need to read the "more info" part. Nevermind my comment.
posted by spiderskull at 5:57 PM on October 7, 2005

Response by poster: argh! I ran out of stamina before typing the last two lines:

...and also a 'phantom volume' called "DragThing 5.6.1," which I guess refers to a disk image that was mounted at the time things all went wrong.
posted by nowonmai at 6:04 PM on October 7, 2005

I'd recommend picking up a copy of DiskWarrior if you can spare the cash.

It has saved what seemed to be a hosed drive for me more times than I care to admit.

Unless there's some crazy physical damage there it will almost certainly get you to the point where you can successfully get your data off.
posted by bcwinters at 6:14 PM on October 7, 2005

Response by poster: Diskwarrior dies of kernel panic. It's Diskwarrior 3.0, which now I think, might not be new enough for a 2003 iBook G4? Alsoft's web site seems not to have such a simple thing as a list of which Macs are supported by which versions of their software.

Ditto Techtool Pro 4.0.1 and Micromat's website.
posted by nowonmai at 6:39 PM on October 7, 2005

Using target mode, can you mount it read-only on the G4? That might allow you to read files without fixing the fs.

By default I think the G4 will attempt to perform a normal read-write mount of any volume it sees on firewire, e.g. the target-mode iBook. If there's some way of preventing it mounting at all, you should be able to run DiskWarrior on the G4 and point it at the target-mode iBook. I'm not an OS-X person so I can't tell you how this would be done, but it's the approach I'd take on any other unix machine.

Last resort would be to pull the physical drive, slap it into a 2.5" external-drive case (they cost very little now), make an image of it and then play with the image. Assuming no physical damage of course.
posted by polyglot at 6:59 PM on October 7, 2005

You should be able to download an updater for DiskWarrior, which will let you burn a new bootable CD. A 2003 iBook should definitely be covered if my 2005 PowerBook is.

I'm going to go back up my computer now, btw!
posted by bcwinters at 7:29 PM on October 7, 2005

If nothing else works, and you are positive that mounting the bad drive as a read-write device causes the OS to hang (which certainly sounds like a bug to me), I recommend you temporily modify the behavior of diskarbitrationd (the Mac OS X disk arbitration daemon, which, among other things, handles automounting of firewire drives).

Create an entry in /etc/fstab on the desktop G4 that matches the iBook in target disk mode. Either specify that the iBook should mount as a read-only device, or specify the noauto option to prevent it from being automatically mounted by the OS when connected and then mount it manually as a read-only device yourself. This will allow you to access the iBook as as read-only device, which hopefully won't hang your G4 (as implied by your tests in single-user mode).
posted by RichardP at 7:59 PM on October 7, 2005

I have a bizarre idea.

See if it mounts in OS9. OS9 was 100% flakier...but just as long as we're searching for answers.
posted by filmgeek at 10:01 PM on October 7, 2005

Exact same thing just happened to me with my Powerbook just three days ago.

I thought it was the filesystem at first, but fsck in single-user mode was ineffective, running disk utility from the install CD didn't really help, and trying to use firewire target mode would crash any Mac I plugged it into.

Eventually, after 4 attempted fscks, the S.M.A.R.T. status started reporting FAILED. I called AppleCare, and I'll have my PowerBook back monday. I don't know if I'll have my data back though. I had most stuff backed up -- All I lost was my Pictures and my accumulated settings.

It's entirely possible that your hard drive is dying. That's what the problem with mine was.
posted by blasdelf at 11:28 PM on October 7, 2005

Response by poster: In case anybody is interested, or Googles their way here in the future with a similar problem, here's how it worked out.

RichardP's suggestion allowed me to connect the iBook to my desktop machine without crashing the latter, but Disk Warrior, Techtool and Data Recovery all barfed on the volume and crashed when trying to scan it.

I was eventually able to boot the iBook from an Ubuntu linux LiveCD, mount the drive read-only and transfer my files to an external hard disk.

Then I was able to go back into Target Disk mode and used Disk Utility from my desktop to reformat, and am now having all the fun of reinstalling everything.
posted by nowonmai at 11:12 AM on October 9, 2005