[clue-tech] Data recovery recommendations?

[Jim Ockers]

Hi Sean,

Sean LeBlanc wrote:
> I have a co-worker who has a Mac that had (what sounds like) an epic
> failure. Any thoughts on what steps they might take? Any local expertise to
> recommend on where they can take the machine to have the data recovered?
>
> I thought about trying to help out myself via Knoppix or the like, but I'm
> not sure I want to do that. From what I understand,the drive itself is making
> serious noises, and actually running it normally may cause even more damage?
>   
I've seen several helpful replies on this list including a place or two 
that you could probably take it to and they would help you out. I've 
done several successful data recoveries over the years, not to the level 
of electron microscope or full drive disassembly of course, but 
effective enough for my purposes. Here is what I would try if I was 
doing this project:

1. Obtain a Linux computer with a kernel that can read the mac partition 
table and filesystems and a spare drive interface port. Hopefully it is 
SATA so it's easier than IDE or SCSI.
2. Install the drive in the Linux computer on one of the spare 
interfaces. Boot the system normally.
3. Observe the kernel messages pertaining to the Mac drive. Can the 
controller see it? Does it show up on a bus scan? Does it have a 
readable partition table?
4. Read the partition table with fdisk -l
5. If the drive is SATA or IDE try to get the SMART diagnostics and see 
what the drive is reporting.

If neither 4 or 5 works then the drive is majorly pooched, and the next 
2 steps are irrelevant.

6. Try to mount the data partition with the appropriate filesystem and 
mount options.
7. Maybe obtain (download?) a Mac filesystem repair utility if it seems 
to have errors. For Windows systems I've used UBCDWIN (ultimate boot CD 
for Windows) for some fairly low level file recovery on bad/failing 
disks with significantly damaged filesystems.
8. ???
9. Profit!

If the drive is majorly pooched, your options depend on the nature of 
the problem. I had one failed drive that was very old and the stepper 
motor that spins the platters was weak and couldn't start the platters 
spinning. Once they were spinning it was fine, it just couldn't start 
them spinning. Of course the drive had important files on it that either 
weren't backed up or the backup was bad or something, I don't remember. 
Anyway I took the housing off the drive and powered it on with the drive 
guts exposed to air, and then I started the platters spinning with my 
finger. I could see the surface of the platters starting to change color 
and also I wasn't in a clean room so I hastily copied the files of the 
disk as quickly as I could before it got contaminated with dust or 
whatever else was going wrong. It worked and I got the files back! This 
is probably not the recommended procedure but it worked for me, YMMV lol.

If you can hear the platters spinning up then maybe the problem is 
something else. If you have nothing really to lose by opening the case 
maybe you can see what's wrong once the drive is open, and help 
something move with your finger (head, platters, whatever) if it's 
stuck. Work fast though!

Good luck,
Jim

-- 
Jim Ockers, P.Eng. (ockers at ockers.net)
Contact info: http://www.ockers.ca/pason.html