Disk content analysis
Content analysis is typically applied for disks coming from a RAID.
Analysis of RAID content allows to get more information about RAID configuration that may significantly narrow the number of variants both for automatic and manual RAID recovery.
To use content analysis correctly, please select RAID member disks individually rather than a RAID as a whole. ReclaiMe Pro analyses content on disks,
which are supposed to belong to the same array thus helping to get more information about the RAID in question like whether all member disks are present.
Content analysis is launched from the Disk and partition list window where all the available
storage devices and created regions are listed. Once you click the Content analysis button, ReclaiMe Pro starts to analyze the content of the selected devices.
Data is read and analyzed in random order. The size of the scan area is limited by the smallest device.
In the Content analysis window you can get the following information:
- Number of bad sectors. When reading a sector, ReclaiMe Pro sends a read request to a device and waits for the response.
If the device fails to respond within a certain time
(timeout in the Real time parameters panel),
the requested sector is considered bad.
- Ratio of zero sectors in data. Keep in mind that ReclaiMe Pro calculates the share of completely
zero sectors rather than amount of zero bytes on the disk. So, if there is just one non-zero byte in a sector while other
bytes are zeros, it is still considered a non-zero sector.
- Data entropy in bits per byte which is calculated across 512-byte sectors excluding zero sectors.
Entropy value is averaged throughout all the non-zero sectors on the disk.
- Mirror map displaying the ratio of identical sectors on the selected devices.
This is available only when several devices are selected.
During the analysis two mirror maps are created — a general mirror map where only non-zero 512-byte sectors are compared and
a block mirror map for RAID1E where blocks of selected size are compared.
- Parity tests providing you more information about the set of disks. For example, you can
catch a hotspare disk or conclude that you deal with an incomplete disk set.
Content analysis progress
At the bottom of the window you can see how much data has been analyzed.
The maximum amount of data available for the analysis is determined by the smallest of the selected devices.
Once ReclaiMe Pro has brought enough data to make a conclusion about data characteristics,
click Stop and return to the list of the devices.
You may find useful to watch our data recovery videos devoted to content analysis in ReclaiMe Pro.