What is Data Recovery Anyway ?
Data recovery solutions are incredibly important to all companies and individuals who must recover lost electronic information. People who want to know what data recovery is must understand that this is the process of retrieving data that is not normally accessible.
This typically occurs when the media containing the data is damaged, usually from physical impact, water or exposure to magnetism.
You may also need a data recovery solutions service when the file with the data becomes corrupted due to a software error, or when the computer loses power while writing to the media.
Data Recovery Solutions
A corrupt operating system is the most common type of data recovery. These files are necessary to use the computer so the recovery of system files is a high-priority. This type of data recovery generally involves copying the system files from the original media such as a CD or DVD.
The software on the media guides the user through the installation process. The installation of an operating system may also include storing system files on a separate partition, eliminating the necessity of using the original installation media.
Data recovery is also needed in the event of a disk-level failure, where the file system or partition becomes corrupted. This type of failure requires the disk to be repaired before the operating system can read the data on the disk. Data recovery software may be able to recover a disk failure caused by a software error.
A disk failure also requires the disk to be repaired or replaced in the event of physical damage to the disk. In this case, the data recovery process includes copying as much good data as possible to the new disk.
Another type of data recovery involves restoring deleted files to the storage medium. This can occur when a user deletes files unintentionally or an intentionally deleted file has information that is needed after all.
The information in a deleted file is typically not immediately erased. Instead, the references to that file are removed from the directory structure and the space occupied by that file is made available for reuse.
Modern operating systems typically have a recovery application that easily restores deleted files.
Physical Damage Data Recovery Solutions
Physical damage to a CD or DVD often occurs when a layer of dye or metal is scratched off the surface. Permanent media such as a disk drive can suffer mechanical failures of the rapidly moving parts inside the disk. The user may be able to recover some of the data on the damaged disk but the physical damage itself requires repair from the disk manufacturer or a company specializing in data recovery.
Common types of physical damage include a faulty printed circuit board, which can often be performed while the disk drive is still under power.
This procedure is known as a live PCB swap. Another common cause of physical damage to a hard drive is a head crash, in which the read/write head strikes the disk platter. This not only damages the platter, it also corrupts the data on the platter. This procedure generally requires the platter is to be installed into a good hard drive.
The repair of physical damage to a disk usually costs more than the disk itself. This type of data recovery requires considerable expertise and it should only be performed when the value of the data on the disk exceeds the recovery cost. The physical repair of a disk generally begins by making a copy of the data on the bad disk using imaging software.
This software operates at a very low level and performs a bit-for-bit copy of the data onto a good hard drive. The data on the damaged portion of the disk is often irretrievably lost. The damaged disk may then be repaired, generally by replacing the faulty parts. Once the disk is working properly, the data can be copied back to the repaired hard drive.
Overwritten Data
It is generally impractical to recover data from a hard disk drive once it has been overwritten. Peter Gutmann presented a paper in 1996 describing the possible recovery of overwritten data with a magnetic force microscope. This type of data recovery is theoretically possible, although it is not currently performed on a significant scale.
Disk scrubbing software generally defeats the recovery of overwritten data by repeatedly writing random data to the disk, making it virtually impossible to read the original data.
Data can be recovered much more easily from a solid-state drive due to the manner in which these drives overwrite data. An SSD stores data in large blocks, which it references logical block addresses.
The SSD writes new data to the oldest block that is marked for deletion. It then updates, the LBA with the address of the new data, preserving data that has been deleted more recently.
Online Recovery
Online recovery involves storing data onto another computer that is accessible over the Internet.
This method is similar to the traditional practice of backing up data except that the user does not have physical access to the backup storage device. This method requires a high-speed Internet connection in order to be practical. It also needs an inexpensive source of online storage.
There are many kinds of data recovery solutions depending on the situation.