End User Raid Zero Array Crash

I had a client call me the other day and tell me that her two year old two terabyte drive had crashed and all of her pictures of her children, as well as her wedding were on the drive. She did not have a backup and was very upset. I knew that there … [Read more...]

View It Now Software Tool

I am a pretty visual guy and because of that my problem solving skills are based on viewing.  When trying to recover data from a corrupt file system I like to use a hex editor and view the system areas of the drive to make sure that everything is … [Read more...]

View It Now NTFS File System Viewer

I have worked with Microsoft file systems since DOS 3.3.  From FAT12, to the current NTFS 5.0 Microsoft has always strived to make their file systems fast and reliable.  However, there has always been one major drawback.  Their file systems have … [Read more...]

Hard Drive Recovery and Remote Diagnostics… Old School gone retro…

When I first started writing hard drive recovery software, many, many, years ago Microsoft file systems were pretty straight forward.  It was a simple FAT, with some file entry tables scattered throughout the drive with a few key system components.   … [Read more...]

View It Now for SNAP OS 4.X

The original SNAP NAS devices were developed by SNAP Appliance.  The operating system that was used was a flavor of BSD in concert with the file system UFS.  Although the file system looks very similar to the original UFS there were some subtle … [Read more...]

Recovering Folder Relationships Using DOS Clustering Design

    In my last installment I described what a file entry record would look like if it were in fact a cluster holding file entry data. I went over the fact that the first two entries of the folder cluster would be a period followed by ten spaces, and … [Read more...]

Using FAT32 File Entry Record For Recovering Folders Using Software Logic

  In my last installment I described the file entry record and its on-disk format.  I used a 'C' structure to denote the different fields of the record and defined which five are most important to us when trying to recover a FAT32 file system where … [Read more...]

FAT32 Recover File Entry Table On-Disk Layout Using a C Structure

In my last installment Recovering FAT 32 With File System Markers, I offered a brief outline of a case that destroyed a FAT32 file systems major components. This was done by formatting the drive using an operating system that is not native to the … [Read more...]

Recovering FAT32 With File System Markers

In my last installment, Recovering FAT 32 with File Entry Records, I talked about USB and Fire Wire devices and how they are susceptible to damage. In addition I spoke about the file system used to store data on these devices as being FAT32 in order … [Read more...]

Recovering FAT32 with File Entry Record Data Only

External USB hard drive devices have been a real 'boon' for the hard drive recovery industry. From the fact that they dissipate heat poorly, they are susceptible to vibration, and your dog walking past your computer happily wagging its tail can … [Read more...]

How platter swelling affects a hard drive

  Okay, I know this is not about how to read bad parity in a drive in order to find a stale drive in a RAID five.  This is an important subject, however, and I also think it is important to know why heat and a swelling platter can cause hard drive … [Read more...]

Partition Types in a Soft Spanned Set

Spanned Set Partition List

  Last time I explained the basic premise of a spanned set.  I used the example of a clients RAID that contained 3 36 GB SCSI drives. In a standard set each one of the drives would use one partiton for the entire drive and then the set would be … [Read more...]

What File System Components are affected by FDISK

As I have mentioned before we have all either by design or by accident fdisked an NTFS file system. In doing so all of the files become inaccessible and the assumption for many years was that they could not be recovered. Many of the more recent … [Read more...]

Recovering from Accidental FDISK using Free Software

Like many of us I have accidentally used 'fdisk' to partition a drive that I had never intended to. Whether it be adding a new drive, repartitioning and formatting a USB device, or just trying to reload the operating system there has been more than … [Read more...]

Recovering a Spanned RAID Set Without RAID Software

  Recently it was my displeasure to work on a three drive spanned set for NT 4.0.  The set was soft configured so when the boot drive went down, with all of the configuration data for the RAID on it, the RAID would not mount.  In addition to that, … [Read more...]

Use Bad Block Frequency to Determine a RAID 5 Stale Drive

We have been discussing the love affair I have with stale drives in a RAID five array and how best to determine if in fact one exists. I explained how the NTFS file system data is normally laid out and the fact that the old and new data, as well as … [Read more...]

Determining a Stale Hard Drive in Most RAIDs

  In my last installment I covered two of the three reasons why we do a parity check.  First we want to make sure that we do not have a stale hard drive in the array.  Although I did not cover how one determines if in fact a stale hard drive exists, … [Read more...]

Analyzing RAID parity

Last time I discussed how to find the RAID data offset for a SNAP OS 4.x RAID handler. To put it briefly it was just a simple matter of finding Cylinder Group zero on the first drive in the array and back tracking 48 sectors. Once the RAID data … [Read more...]

Finding SNAP OS 4.x RAID Data Offset

If you are in this business long enough you will see everything, or will you?  Two weeks ago I received a SNAP RAID OS 4.x for recovery.  I have done a lot of these and I am pretty familiar with the data offsets, how the drives are setup, and where … [Read more...]

Check Your RAID Consistency Before A Rebuild

Over the years one of the most consistent problems with RAID recovery is the rebuild. I would estimate that nearly 40 percent of the RAIDs that we cannot recover are due exclusively to the fact that a technician executed a rebuild before verifying … [Read more...]