Recovering a dead drive

Disclaimer: I’m certainly no expert in the area of data recovery, and I will not take any responsibility for damage of you, your or anyone else’s hardware/data caused by following these ideas. This entry is nothing more than a diary of what I did for my and other people’s future interest or reference.

Recently I received a Windows XP machine which “wouldn’t start up”. The BIOS would simply output “A error reading disk drive” after the POST. Note this isn’t the same error as “Insert system disk” etc.

I proceeded to check the obvious, trying every boot order and boot option in the BIOS, all without avail. I then booted Knoppix and attempted to mount the data partition (what was C: in Windows), without success.

Important note: I made two stupid mistakes here. Firstly, I tried to initially mount it in Konqueror, and secondly I tried to mount it read/write. If you’re suspicious of a device’s health, mount it readonly and mount it via the terminal. It’ll possibly save your data and save you some wasted time.

I then tried to mount it from a terminal, but I received a variety of errors regarding DMA read failures. I proceeded to disable DMA (K Menu/KNOPPIX/Utilities/Harddisk/CD/DVD DMA Acceleration) and tried again. Still read errors.

At this point I plugged in an external 500GB hard drive (USB) and started an ntfsclone with the command

ntfsclone -o /mnt/sda1/hda1.img -s --rescue /dev/hda1

Whether due to the computer’s USB speed speed or (more likely) the HD’s state, it took about 9 hours to copy 10GB of data off. It unearthed several hundred unreadable sectors in the process.

It’s important to note at this point (if you’re not familiar with the NTFS tools) that the “-s” switch for ntfsclone causes it only copy parts of the filesystem which are actually in use. That means it does not do the same as:

dd if=/dev/hda1 of=/mnt/sda1/hda1.img conv=noerror,sync bs=8k

I’ll probably go down the same route as before, using my Autopsy script to get off what good sectors I can. But the above commands and flags might just make some else’s life a little easier.

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