Data recovery in computing language is known as the process of salvaging or retrieving the lost, inaccessible, damaged and formatted data from the secondary memory devices. This process is implemented when the data cannot be retrieved in a standard way.
Data recovery process is required due to the physical damaged and the logical damage, which damages the file system and is prevented from mounting by the operating system of the device.
The various reasons for data recovery are failure of operating system, hardware malfunction, and logical failure within the software, physical damage and accidental deletion of the data. The most primary step is to copy the the data of the hard disk or create an image of the hard disk onto another other storage device.
Various Recovery phases.
In some cases there is only a minute damage to the physical drive and by changing some physical parts data can be easily retrieved from the device. But for logical damage first every byte of readable data is recovered using imaging techniques onto a reliable medium after that the disk is analyzed for logical damage for the reconstruction of the file manager.
- Phase 1 (Hardware): The first step involves that the physical damage to the hardware should be repaired so that the hard disk can function enough to read the data from the hard disk. Then the data should be copied onto another memory disk to avoid data corruption.
- Phase 2 (Software): Firstly the image of the drive is formed on to another drive such that there exists a copy of the data and then the operations of recovering the data can be employed. When logical error takes place mostly it is due to the corruption of the file manager which prevents mounting, in which the data is not made visible to the user by the operating system and to retrieve the data Live CD is used which is bootable computer software installation that directly runs through the ROM rather than from the hard disk drive. So it can run even when the hard drive is corrupted to retrieve the data. Software recovery is considered over the hardware recovery because it is easy and more efficient than hardware recovery which needs professionalism.
The hard disk drive is a delicate device and it should be handled with care and it is always preferred that the partitioning of the hard disk should be done such that directories, firmware and important files of the system are stored in another drive such that the recovery can be done easily.