RAID Wiederherstellung
R-Studio detects and treats valid software or hardware RAIDs as regular
drives/volumes. But what to do if you have only drives or drive images
of a faulty RAID? R-Studio can still help you to get the data back,
provided that the drives necessary for the RAID to operate are working
or you have the images of those drives. The number of drives needed in
order to get data back depends on the RAID layout. For example, for a
mirror (RAID 1) of two drives, at least one must be valid, whereas for
a RAID 5 of three disks, the number of valid drives should be two.
Working with RAIDs in R-Studio is based on the concept of virtual
volume sets and RAIDs. That is, you can construct the original RAID
from its drives and/or drive images in R-Studio and process it as you
would any other device object. Such a virtual object can be searched
for files and scanned, and files found on it can be recovered in the
same way that they would from normal drives/volumes.
Virtual RAIDs can be constructed using any device objects visible to
R-Studio, be they hard drives, logical disks, or images.
Please note that virtual volumes and RAIDs are purely virtual objects,
and R-Studio does not write anything on the devices from which such
objects are created.
Let's start the process of learning how to work with RAIDs in R-Studio by creating a simple RAID 5:
Creation of a Simple Virtual RAID 5
Parameters:
1. Number of disks: three
2. Objects in R-Studio: SCSI(3:0), SCSI(3:1), SCSI(3:2)
3. Block Size: 64 KB
4. Offset: 0
5. Block order: Left Asynchronous (Continuous)
Where PD stands for parity of data
To create such a RAID, we
1. Click the
Create virtual volume sets or RAIDs button and
select
Create Virtual Block RAID. The newly created virtual RAID5 object
will appear on the
Drive pane, and the
Parents tab will appear on the
R-Studio Main panel.
Check that
Apply changes immediately is selected.
2. Drag the objects from which we want to create the RAID5 to the
Parents tab and
place them in the correct order, that is, SCSI(3:0), SCSI(3:1), SCSI(3:2).
3. Specify the correct blocks order and offset (in sectors). As soon as
R-Studio detects a valid file system, a new Partition 1 object will
appear on the
Drive pane.
We may process this partition as a real object.
Let's enumerate the files on that partition. Just double-click the
object and see the folder/file structure on the virtual RAID 5.

We can check that we constructed the RAID5 correctly. Just double-click a graphic file, and R-Studio will show its preview.

Please note that you have to specify each RAID parameter correctly-be
it the device order, offset, block order, and size-to obtain real data.
R-Studio sometimes might detect an object with a valid file system even
if one of the parameters is not correct, so it is a good idea to
preview a file-the larger the better-to verify that you have
constructed the RAID correctly. Use this formula to determine the
minimum recommended size:
Block size * (number of disks -1)
For our case that minimum file size would be 64KB (the block size) three disks minus one disk (2), which comes to 128KB.
You may also create your own RAID configurations, save them, and then
edit and reload them. If some of the objects are missing, you may
substitute them with Missing Disk or Empty Space objects. See R-Studio
documentation for details.
Turning Disks On-Line and Off-Line on the Fly
You may turn the objects in the virtual RAID or volume set online and off-line by selecting/clearing the
On check box on the
Parents tab. It may be useful, for example, if you need to see which disk is non-actual in a RAID 5.
Actually when you turn an object off-line, R-Studio substitutes it
internally with a missing disk object equal to the size of the off-line
disk.
Now we can proceed with a more advanced example.
Creation of an Advanced Virtual RAID 5
Now we will use the drive images as the objects from which we will create the RAID5
Parameters
1. Number of disks: three
2. Objects in R-Studio: disk image files: Y:\Disk1.dsk, Y:\Disk2.dsk, Y:\Disk3.dsk
3 Block Size: 4 KB
4. Offset: 64 KB
5. Block order: Custom
|
PD
|
1
|
2
|
|
PD
|
3
|
4
|
|
PD
|
5
|
6
|
|
7
|
PD
|
8
|
|
9
|
PD
|
10
|
|
11
|
PD
|
12
|
|
13
|
14
|
PD
|
|
15
|
16
|
PD
|
|
17
|
18
|
DP
|
To create such a RAID, we
1.Click the
Create virtual volume sets or RAIDs button and select
Create Virtual Block RAID. The newly created Virtual Block RAID object will appear on the
Drives pane, and the
Parents tab will appear on the R-Studio Main panel.

Check that
Apply changes immediately is cleared, as we will be doing a lot of
editing here and there is no reason to have R-Studio execute changes unless we
are through.
2. Drag the objects from which we want to create the RAID 5 to the
Parents tab.

Then place them in the correct order, that is, Y:\Disk1.dsk, Y:\Disk2.dsk, Y:\Disk3.dsk.
Select RAID5 in the RAID type, and enter the block size and offset on the
Parents tab. Disregard the
Block order field for the time being.
3.Manually enter 9 to the
Number or rows field on the
Parents tab. The
Block order field will change to
Custom.

Enter the block order in the table on the
Parents tab.
Using the keyboard: Arrow keys to navigate, digit and P keys to enter the block order.
Using the mouse: Right-click the cell and select the number or parity
from the shortcut menu. If the block table is too large, you better
use the keyboard to enter the digits.
Corrections: R-Studio will indicate if some digits are not
correct by marking the cell with the red color Navigate to the required
cell and enter the correct value. Use the
Delete key to clear a cell.
Clear the table: Right-click the table and select
Clear all on the shortcut menu.
4. When we finish filling the block order table, click the
Apply button on the
Parents tab.

As soon as R-Studio detects a valid file system, a new Partition 1 object will appear on the
Drive pane. We may process this partition as
a real object.
Let's enumerate the files on that partition. Just double-click it and see the folders/files structure on the virtual RAID 5.

We can check that we constructed the RAID 5 correctly. Just double-click a graphic file, and R-Studio will show its preview.

You may also create your own RAID configurations using the description
file for RAID configurations. See R-Studio documentation for details.