What is Data Recovery?

Data recovery refers to the rescue of electronic data stored on desktop hard disks, notebook hard disks, server hard disks, server hard disks, storage tape libraries, mobile hard disks, USB flash drives, digital memory cards, Mp3 and other devices through technical means And recovery technology.

The so-called data recovery technology refers to the technology of retrieving data through a certain method and means so that information can be regenerated when a computer storage medium is damaged and some or all of the data cannot be accessed and read. Data recovery technology can not only recover lost files, but also recover physically damaged disk data and data from different operating systems. Data recovery is a remedy after a problem with computer storage media. It is neither a precautionary measure nor a backup. Therefore, there are some special cases where data will be difficult to recover, such as data being overwritten, low-level formatting, and severe damage to the disk. ^[1]

1. Soft recovery:

It is mainly to restore the data of the operating system and file system layer. This kind of loss is mainly caused by software logic failures, virus Trojan horses, and misoperations. The physical media has not been substantially damaged. Generally speaking, it can be repaired. Some specialized data recovery software have this feature. Kind of ability. Among all the soft damages, errors in the system service area are more complicated, because even if the same model of hard disk produced by the same manufacturer, the system service area is not necessarily the same, and manufacturers generally do not publish the content and read of the system service area of their products. Instruction code.

2. Hard recovery:

It is mainly aimed at data that is lost due to hardware failure, such as hard disk circuit board, disk body, motor, track, disk, etc. or system failure caused by hard disk firmware system, etc., the recovery is generally difficult. At this time, please pay attention not to try to repeatedly power on the hard disk, it will not artificially cause a larger area of scratches, so it is possible to recover most of the data.

3. Database system or closed system recovery:

This part of the system is often very complicated, and has its own set of complete protection measures. General data problems can rely on their own redundancy to ensure data security. Such as SQL, Oracle, Sybase and other large database systems, as well as MAC, embedded systems, handheld terminal systems, instruments and other systems are often more difficult to recover.

4. Coverage recovery:

Restoration is very difficult. In the general civilian environment, because the resources required are too large, they often lose more than they pay. However, it can be done in the state-of-the-art defense military and other countries or by individual hard disk manufacturers with advanced technology. The specific technology involves core secrets and cannot be detected. ^[2]

1. Human error operation

Sometimes we accidentally delete files while using the computer, or accidentally format the partition, resulting in data loss.

2. Destruction of malicious programs

The most common malicious program is a virus. Generally, viruses do not cause data loss, but some viruses may cause hard disk lockup, partition loss, or data loss.

3. System or software error

For example, at work, a crash caused by a bug in the operating system or the application itself will cause the loss of working documents, and sometimes it will bring some problems such as affecting system compatibility and stability when upgrading the system or updating the application. The problem.

4.Hardware failure

Data loss or irrecoverability caused by improper operation, accidental power failure, excessive use time, etc., caused by disk failure and unstable power supply.

5. Natural factors damage

Data may also be lost due to humidity, sand, lightning, and accidents (such as electromagnetic interference, earthquakes). Of course, this factor is relatively unlikely. ^[1]

3 ways to prevent data loss:

1.Never save your file data on the same drive disk of the operating system

We know that most word processors save the files you create in My Documents, but this is exactly the least suitable place to save files.

Logical fault data recovery

Logical failures are failures related to the file system. The hard disk data is written and read through the file system. If the disk file system is damaged, the computer cannot find the files and data on the hard disk. Data loss caused by logic failures can be retrieved through data recovery software in most cases.

Hardware failure data recovery

Hardware failures account for more than half of all data accidental failures. There are often circuit failures caused by lightning strikes, high voltages, high temperatures, mechanical failures caused by high temperatures, vibration collisions, and physical bad track sector failures caused by high temperatures, vibration collisions, and aging of storage media. Of course, accidental loss of damaged firmware BIOS information, etc.

The data recovery of hardware failure is of course the first diagnosis, the right medicine, first repair the corresponding hardware failure, and then according to the repair of other soft failures, and finally the data is successfully recovered.

Circuit failure requires us to have a circuit foundation, and we need to have a deeper understanding of the detailed working principle flow of the hard disk. Mechanical head failure requires a level 100 workbench or workshop for diagnosis and repair. In addition, some software and hardware repair tools are needed to repair fault types such as the firmware area.

Disk array RAID data recovery

The storage principle of the disk array is not explained here. You can refer to the array knowledge article on this site. The recovery process is also to remove hardware and software failures, and then analyze the array order, block size and other parameters. Use array cards or array software to reorganize or use DiskGenius virtual Reorganize the RAID. After the reorganization, you can recover data in the usual way. ^[4]