Mounting external drives in single-user mode?

Sigh. What were the odds of the HD on my month-old MacBook Pro and the HD on my somewhat older one (which was filling in for the moment as a backup) failing on the same night? Pretty low, I'm guessing, but that's what has happened. The Genius Bar has confirmed that the new drive is completely toast, and Apple is replacing it now, but of course they can't salvage the data. As for the old drive, while it won't boot and isn't visible to other machines in target disk mode, I am able to mount it in single-user mode and even view text files. What I can't seem to do is mount my external FireWire/USB2 drive so that I can try actually copying the files off.

I've re-read the man page for "mount" in hopes of discovering the correct incantation, but so far it has eluded me. I've been trying things like "/sbin/mount -w /dev/disk1 /Volumes" and "/sbin/mount -w /dev/disk1 /Volumes/rescue", which return "Permission denied" and "No such file or directory" respectively...not sure that's the right device, but finding an acceptable mount point seems to be an issue regardless. Hoping someone can point me in the right direction, and thanks for reading.

MacBook Pro, Mac OS X (10.5.8)

Posted on May 22, 2010 10:34 PM

Reply
4 replies

May 22, 2010 11:41 PM in response to macbig

Thanks, macbig...no joy yet, but definitely a helpful link.

I've confirmed via System Profiler on laptop #3 that my external USB drive is formatted as MS-DOS FAT32, so mount_msdos seems like the right utility to use. (The drive shows up there as /dev/disk1s1.) Meanwhile, "ls /dev/disk*" on the problem machine returns the following:

/dev/disk0 /dev/disk0s1 /dev/disk0s2 /dev/disk1 /dev/disk1s1 /dev/disk1s2 /dev/disk1s3 /dev/disk2 /dev/disk2s1

I've created /Volumes/rescue as a mount point and tried most of those devices with "/sbin/mount_msdos [device] /Volumes/rescue", with the following results:

/dev/disk1:
mount_msdos: Unsupported sector size (0)
/dev/disk1s1:
mount_msdos: Unsupported sector size (1)
/dev/disk1s2:
mount_msdos: /dev/disk1s2: Bad file descriptor
/dev/disk1s3:
mount_msdos: Unsupported sector size (0)
/dev/disk2:
mount_msdos: Unsupported sector size (64543)
/dev/disk2s1:
kextload: cannot resolve dependencies for kernel extension /System/Library/Extensions/msdosfs.kext
error loading extension /System/Library/Extensions/msdosfs.kext
mount_msdos: msdos filesystem is not available

Based on this, I'm guessing that disk2s1 is the device I want. Unfortunately, when I try to poke around in /System/Library/Extensions, I'm getting I/O errors...gah. I have a bad feeling about this.

This thread has been closed by the system or the community team. You may vote for any posts you find helpful, or search the Community for additional answers.

Mounting external drives in single-user mode?

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.