Tip - Data recovery from a disk image
02 09 09 - 21:46 If you have a disk image of a corrupted drive that you're trying to recover from, you may find when you double-click it, it won't mount due to filesystem corruption. It is then detached from the /dev node it had because of this, and you can't use it. But suppose you want to use something like Prosoft Engineering's Data Rescue II on it.If you attempt to use hdiutil to attach it from Terminal, this is what you get:
$ hdiutil attach Macintosh\ HD.dmg
hdiutil: attach failed - no mountable file systems
The right way to do this is this - the "nomount" option stops it from attempting to mount, so instead it just attaches and doesn't fail.
$ hdiutil attach -readonly -nomount Macintosh\ HD.dmg
/dev/disk2
(-readonly is not required but may be useful).
Now you can recover from it.
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