Disk cloning with ByteBack D.R.I.S.^TM

The first thing a professional data recovery engineer will attempt before performing any repair or recovery operation, is cloning the problem disk. No matter how simple the problem may seem at first sight, a cloned disk offers a good safety net in case the recovery doesn't go according to plan, or actually causes more damage.

Cloning a disk first offers several key advantages:

• You can perform your repairs on the clone. If the repairs don't work out as planned, you still have the original disk in it's unmodified state, so you could create another clone to try again.

• In case of bad sectors, often repairs can not be made on the original (bad) disk. If bad sectors exist in areas on the disk that contain disk structures, repairing these structures is going to be impossible because writing to bad sectors is impossible. Cloning the bad disk to a good disk will give you a much better chance of repairing those damaged structures.
  Be prepared for the fact that cloning a bad disk to a good disk can take a considerable amount of time.

Having said this, you can safely make repairs on a physically healthy disk using ByteBack D.R.I.S.^TM. If repairs do not bring the desired results (access to your data) or even make matters worse, you can undo all repairs you have made, if these repairs were performed by the ByteBack D.R.I.S.^TM's Analyze & Repair option. If you can be certain that the disk needing repairs does not have any physical defects (bad sectors) and you don't have a spare disk handy for cloning, you can forego the option to clone a disk. You can check a disk for physical defects by running a surface scan.

Many of the 'conventional' cloning products, disk copiers and disk imagers are not particularly good at handling disks containing bad sectors or corrupt disk structures. The ByteBack D.R.I.S.^TM cloning feature is designed to handle disks that contain unreadable areas, and to ignore any damage in disk structures such as partition tables and file systems. Keep in mind though that the ByteBack D.R.I.S.^TM clone feature does not offer the functions that 'conventional' imaging tools offer, like resizing partitions; clone is meant to facilitate recovery.

  Considerations:

• if you have a disk that's dying (bad sectors are appearing) you should keep in mind that each time you read that bad disk, it could be the last time. Clone this disk as soon as you can! 

• you need to decide how to handle bad sectors and read errors before you start cloning the disk. If you use default settings, each bad sector that is encountered will be read a maximum of 32 times to see if data can be read. This can make cloning a bad disk very slow. You can change the number of read-retries in the "options" menu. Setting this to 0 (zero) will disable read-retries.
  Another setting that affects the clone process is the maximum number of read errors that are allowed before ByteBack D.R.I.S.^TM aborts the process. The default setting for maximum read errors is 32, meaning that after 32 read errors ByteBack D.R.I.S.^TM will interrupt the current process and ask you how to proceed: ignore further errors, reset the number of errors or disable errorchecking. You can change the maximum read-errrors setting in the "options" menu. Setting this to 0 (zero) will disable read error checking.

• The target disk for the clone should be at least the same size as the source disk. The target disk is allowed to be smaller, but ByteBack D.R.I.S.^TM will warn you if this is the case. Obviously, if the target disk is smaller, a part of the source disk will not be copied; so this is generally not a good idea!

• Disk Cloning may take quite some time and both disks will be active continuously. Because of this the disks may get hotter than during normal operation. Consider opening the PC casing and blowing in cool air using a fan placed at approximately 1 meter from the PC for extra cooling. If you do not apply additional cooling, do not remove the case!

• If a disk does not respond well to cloning start-to-end, it might pay off to try a reverse clone. The source disk will then be read end-to-start. When starting the clone operation, you can select how to clone a disk: normal (start-to-end) or reverse (end-to-start). Note that reverse cloning is considerably slower.

• As every read error is logged, the logfile may expand in size up to a point where no room is left on your ByteBack D.R.I.S.^TM boot diskette. Consider disable logging while cloning a disk that is in really bad shape.

The Procedure

Before starting the clone, decide on how you want ByteBack D.R.I.S.^TM to handle unreadable sectors on the source disk. Default behavior is that ByteBack D.R.I.S.^TM will attempt multiple re-reads (32) when encountering read problems. To change the Read-Retries setting select [Options], [Read Retries] and enter the desired number of re-read attempts per unreadable sector. Select a value in the range 0 - 32, where 0 will disable read-retries.

If you use the default settings, ByteBack D.R.I.S.^TM will interrupt the clone process after 32 read errors. You may not be aware of bad sectors on the source disk, so leave the default setting of maximum read errors to 32 if you start a clone operation and do not not know what the physical state of the source disk is. If you know beforehand that the source disk is in bad shape (has many bad sectors) you might wish to disable the maximum read error warning to make sure the clone continues uninterrupted. To change the maximum read error handling, select [Options], [Max ReadErrors] and enter the maximum read error threshold. Select a value in the range 0 - 255, where 0 will disable the maximum read error warning.

Important! Your destination disk must be error free! If ByteBack D.R.I.S.^TM encounters a write error on the target disk, the clone is aborted!

To clone a disk:

Note: it is assumed you have already selected the *source* disk!

Select  [Disk Operations], [Clone]. Select the *destination* disk from the list and enter a range (accept defaults to clone the entire disk). Select the Clone Type ([From Start to End] or [From End to Start]. Confirm your selected options to start the cloning.

Note: If ByteBack D.R.I.S.^TM encounters areas that can not be read the 'estimated time remaining' may increase dramatically. Once the bad areas are processed the 'estimated time remaining' will decrease again.