RAID 0 - As data is read sequentially from the RAID set, it comes first from the first component drive until a
stripe-sized amount has been read, then the next data comes from the second component drive, and so on, in
round-robin fashion.
JBOD - This is not an official RAID level, but rather a way to make multiple hard drives appear as one big drive
by concatenating them together. As data is read sequentially from the RAID set, it comes first from the first
component drive, until the end of that drive is reached, then continues coming from the second component drive,
and so on until the end of the last component drive.
New in Data Rescue 5 is the Auto-Detect button which will enumerate through each supported RAID type and
common stripe sizes (if applicable) and performs a quick scan with each configuration. If files are discovered through
the scan, then that configuration state is saved. When completed, a list of states discovered will be presented and a
result can be chosen.
Once the RAID set has been added, it can be selected to scan for data. In some cases, data may not be opened
properly when recovered if the drives are not arranged in the correct order.
8.5 Recover Options
In Professional mode the Recover button provides advanced functionality beyond what Standard mode provides:
Destination folder is the location where files will be recovered to. Make sure to pick a folder that is not on the
source drive you just scanned.
Merge files into existing folder : when enabled, any files saved are merged into a previous recovery folder if it
exists. Otherwise a new recovery folder is created. This option is helpful to reduce recovering duplicate data that
may have already been recovered.
Existing file behavior determines how Data Rescue recovers a file if it determines the file has already been
recovered
Recover with New Name: a new unique file name is generated and used instead. This is default.
Overwrite: the file will be overwritten.
Skip: the file will not be recovered, only if the file sizes match.
8.6 Secure Erase Tool
The Secure Erase tool, accessible from the View menu while in Professional Mode, allows you to easily erase the
selected drive. The tool will overwrite each sector with the given pattern, or a random pattern. Patterns can be entered
as a hex value or numbers and letters. For example, “\xAB” is the equivalent to 0xAB hexadecimal. Secure Erase does
not format the drive with a file system, this must be performed using the operating system’s drive utility. Please note
that the entire drive is overwritten and all existing volumes will be lost.
8.7 Number Sectors Tool
The Number Sectors tool is a simple tool that assists with guessing the order of drives in RAID-like devices. Each
sector of the drive that is seen by the operating system will have its sector data be the number for that sector. For
example, sector will be “0” in ASCII followed by 511 NUL bytes. Same with “1” for sector 1, etc. Once written (or
enough to satisfy a limit), the device can be disconnected from the computer and each individual drive member can be
examined to determine where the number sequences start and stop. Please note that this tool, like Secure Erase, will
permanently overwrite sectors that it touches and data loss can occur.
8.8 Allocation Blocks Layout
Allocation Blocks Layout can be used after a Deep scan if the files listed by the Found Files results are not opening
properly after recovery. If none of the files open when they are first recovered, selecting this feature will provide you
with additional options which may correct the way the files are found.
During its scan, Data Rescue determines some possibilities for the proper Allocation Block Layout setup. The Block
Size is the number of bytes of the allocation block. The Offset is the number of bytes (represented in hexadecimal),
from the start of the media to the start of the file system.
The first choice is the default selection that Data Rescue considered to provide the best results, but if the files are not
recovered properly, try each of the other selections.
To find the best allocation block layout for recovering files: