Disk partition Dead

[dosuna11]

I have a firewire 400 external HD partitioned into 3 drives. One of my 3 partitions went down. I loaded up disk warrior and it could not repair that partition. I am now backing up my other two partitions. I am sure I backed up what was on that partition but there is always that sinking feeling like maybe I missed something. Any ideas on how to retrieve the data from that dead partition?

[bayswater]

I lost a 2T partition a few months ago. I tried all the demos I could find, and ended up buying Disk Drill because it did a little better than the rest at finding files. In the end, it only recovered about 25% of the files it said it found. It took about 3 days to complete the recovery. I suppose it depends on just how bad the condition of the data is. It won't cost any more than some time to try the demos.

[mikehalloran]

The only thing that DW can repair is the directory. If the directory isn't the issue, DiskWarrior can't repair it.

I have never actually had DW successfully repair or recover anything - ever. I use it as a preventative maintenance and diagnostic tool only. If you have to constantly repair a drive, it's time to recover your files and get rid of the drive.

Have you tried apple's Disk Utility? It's the best tool I know for the use.

First, recover all your files to a known good drive. If there are any system or DP files, do not copy them - instead use Time Machine, Migration Assistant or clone the partitions. If you have to buy a new drive for this purpose, then do so and make that step one. USB 2 is fine - it does not have to be a FW drive.

Now, use Disk Utility to try to repair the entire volume. Don't just try to repair the partition, you have almost no chance of success. Run DU as many times as it takes. Only give up if you see the identical results three or more times in a row. It's not unusual for DU to repair one or two problems at a time. As long as things change, keep running it. If you are successful in bringing it back, immediately pull all the data off - again, Time Machine, Migration Assistant or clone.

If successful, do a low level format that writes all data to zeros if you can - I am not certain that's possible via FW anymore. It is via USB. A low level format re-writes the sector map around any bad sectors and may let you save the drive. If the drive hangs while doing so, it's time for the recycle bin.

Time to re-think your backup plans.

A 3T Time Capsule via ethernet backs up my entire network. Actually, I have two now as OS 8 lets me alternate them automatically (only one has wireless and internet enabled).

[dosuna11]

I looked into my backups and there was a copy of everything. On to DU.
Thanks.

[mikehalloran]

I looked into my backups and there was a copy of everything. On to DU.
Thanks.

Great. I once had to run it over 50 times to bring a disk back. Of course the drive was in terrible shape and needed to be replaced but still it worked. Every run gave me different results so I knew it was fixing things one or two at a time.

Then again, what is your time worth? If you have backups for everything, try a low level format and see if the drive survives (resisting the urge to follow that alliteration).

When you restore your data, there is no longer any reason to partition a FW drive attached to an Intel Mac. eSATA or USB sometimes, yes, as you can boot from those but not FW. Back in the PPC days...

If you pop the case, you can get the codes off of the raw drive, go to the Seagate or WD web sites, punch the codes in and find if the disk is under warranty. If the drive is over 5 years old, forget about that.

Seagate wants you to run some tests that can only be done with a PC. If they determine the drive is actually good, they say they'll charge you for the return. I've never had that happen but the refurb units I get back don't last very long so I don't bother anymore. Sad but true as they used to be considered the best.

WD has a "no questions asked" policy - if the codes show the drive is under warranty, you can generate an RMA online. Expect to see a refurb in about 2 weeks or less.

Unfortunately, unless you had OWC install the eSATA port in your iMac, you are incapable of reading the S.M.A.R.T diagnostics that give you early warning of impending HD failure. I inquired over at TechTool and they told me that Apple is writing code that may let it work over Thunderbolt but no one has designed a cable that lets it work (yet? ever?)

[dosuna11]

The only thing that DW can repair is the directory. If the directory isn't the issue, DiskWarrior can't repair it.

I have never actually had DW successfully repair or recover anything - ever. I use it as a preventative maintenance and diagnostic tool only. If you have to constantly repair a drive, it's time to recover your files and get rid of the drive.

Have you tried apple's Disk Utility? It's the best tool I know for the use.

First, recover all your files to a known good drive. If there are any system or DP files, do not copy them - instead use Time Machine, Migration Assistant or clone the partitions. If you have to buy a new drive for this purpose, then do so and make that step one. USB 2 is fine - it does not have to be a FW drive.

Now, use Disk Utility to try to repair the entire volume. Don't just try to repair the partition, you have almost no chance of success. Run DU as many times as it takes. Only give up if you see the identical results three or more times in a row. It's not unusual for DU to repair one or two problems at a time. As long as things change, keep running it. If you are successful in bringing it back, immediately pull all the data off - again, Time Machine, Migration Assistant or clone.

If successful, do a low level format that writes all data to zeros if you can - I am not certain that's possible via FW anymore. It is via USB. A low level format re-writes the sector map around any bad sectors and may let you save the drive. If the drive hangs while doing so, it's time for the recycle bin.

Time to re-think your backup plans.

A 3T Time Capsule via ethernet backs up my entire network. Actually, I have two now as OS 8 lets me alternate them automatically (only one has wireless and internet enabled).

I finally hit the disk repair one more time and wow it came back repaired. I am able to mount the drive on the desktop. It took seven times. I imediately backed up the data again on a newer drive. Thanks again for the solution.

[HCMarkus]

Fantastic!

Great tip Mike!

[Thomas.B.]

In over 15 years of using Macs with OS 7 - OS X and trying every disk recovery utility under the sun I was completely unaware that I could run Disk Utility multiple times on a hard drive clone to salvage lost data.
Mike - thanks so much for sharing!

[williemyers]

Mike, this is really helpful info, thanks for it! A clarification, if I may...
Using Disk Utility, would you run "Verify" before running (multiple) "Repair"s? or just go straight to "Repairs"?
And if you'd run "Verify" first, and get good results, would you continue on to run "Repairs" anyway?
thanks

[mikehalloran]

I never run "Verify" unless on a startup disk - those cannot be repaired other than Permissions. If problems found, you must boot from another disk to run Disk Utility and repair anything (again, other than Permissions).

[dosuna11]

I did not run verify.