Data recovery processes from Linux systems work on the same basic principles like other systems, but the mechanism of operations are different in nature. Linux volumes support many types of file systems including fat-12/16/32 and EXT-3/4 versions. There are many types of open source software systems available for Linux file recovery. Since the Linux operating system itself is made of Open source systems, you will be able to find many similar recovery kits online, which are compatible with all flavors and versions of Linux. Linux is one of the few operating systems like UNIX which stays relatively free from virus attacks. Moreover the source code of many flavors of operating system is available for modifications to developers, so it is still undergoing many changes to get protection from Logical failures.
However it is possible for the OS and hardware component to fail during run time, just like any other system. In such cases you need reliable hardware and software tools for data recovery and restoration. Our technical team comprising of software and hardware engineers have been developing customized tools for data recovery from Linux based disks. You will be able to take the backup of restored data onto external drives like USB, Pen drive, DVD and other media in a safe manner. Our data recovery techniques are based on hardware and bitwise algorithms to ensure complete restoration from the most critically damages hard drives also.
The scanning methods deployed by Linux data recovery experts have various options for the HDD. Scanning probe microscopy: – This is one of the methods which are common. This method uses a 3-D topographical imaging of the disk surface at the minuscule levels. With this type of probing the technician will be able to determine most types of surface defects in the disk.
Magnetic-Force-Microscopy: – This is another method of deep probing into the platters of disk drive. By using this method, the tool will be able to detect the complete set of old data written on the tracks and sectors of the disk drive, even after they have been overwritten with new files. When this hardware tool is sued along with OEM software from the product manufacturer, it is possible to recover most of the lost, corrupt and overwritten data from each sector in a bitwise manner. This is said to be one of the specialties of Linux based data recovery solutions.
The layers of data in the core disk areas that contain images of all the previously written data get gradually diminished with time. This is the reason for the data recovery experts to recommend immediate action when data is lost or gets corrupt. The images will be large enough for the hardware and software tools to detect them easily and increase the probability of maximum data recovery with ease.
Scanning-Tunneling-Microscopy: – This method of probing also goes deeper into the tracks and sectors of the disk drive, but it explores the sectors with the help of a probing-tip that is made of nickel metal. The diagnosing method goes into the bit level of tracks and sectors in the disk platters, starting from track zero of platter-zero till the last track of the last platter in the disk. The OEM software supplied along with the hardware will be able to remember the bitwise data and its links to other parts of the same file based on the previously stored images in the tracks and sectors. By the end of scanning, the system will be able to create a clear image of the previously stored data which has been lost due to physical damages and/or logical failures of the disk drive. With the help of the software tools, the system can recreate the entire data structure and copy it into an external drive. When this task is performed by a certified data recovery expert you will be sure of getting 100% of your lost data within a matter of few hours, depending on the size of data and intensity of damages sustained by the HDD.
Besides these tools the data recovery technician will have access to many other hardware apparatus for repairing and replacing failed disk read-write head, platter plates, spindle parts and motor, PCB components and firmware ROM etc. these methods are adopted when the level of hardware failure is critical in nature.
Open source software tools
If the nature of disk corruption is logical you will be able to use many open source software tools like DDRESCUE, GPAARTED-LIVE, R-STUDIO, F-RESCUE and STELLAR systems. In this session you will be introduced to some of the salient features of DDRESCUE and the way it functions to recover data from Linux based HDD.
Algorithm of DDRESCUE
If you happen to be a programmer, you would certainly love the way in which an algorithm works, since it is the basis on which software coding is written. DDRESCUE uses 6 levels of algorithm which encompass map file reading, copying, trimming, scrapping, retrying and map file writing.
In the first stage the system tries to search for a map file marking all the corrupt sectors and tracks which have been obtained from previous scans. If no map file is available, then the system considers all the tracks as untried and maps the entire disk area.
In the second stage, the system reads only the good parts of disk and skips the damaged parts. Even those areas which take longer time to read are skipped. Data from the good sectors is copied onto a secondary storage device. In the subsequent stages the system reads corrupt sections. Then the trimming process takes care of large blocks of untied bad data sectors and recovers maximum possible data from them. Scrapping stage leaves out irrecoverable data and moves ahead, by marking such sectors as BAD. The last stage of RETRY reads through all the bad sectors once again and tries to recover most of the data from damaged sectors. Once the complete set of data is recovered, it is written onto the secondary storage device completely. The mapping of process is written onto a Map file which can be used in the future.