In the first article on data recovery, we will talk about the reasons why data is most often lost from disks of workstations and servers, give some recommendations for increasing the reliability of data storage, and advise what to do if you find that some or all of your files disappeared.
Why data disappears :
Although the reliability of modern computer systems is generally quite high, failures occur from time to time due to hardware malfunctions, software bugs, computer viruses, and user, system administrator, and technical personnel errors.
Analyzing the causes of emergencies encountered in our practice that led to data loss, we can say that all of the listed failures happen with approximately the same probability.
Hardware failures :
The disappearance of data can be caused by the failure of various devices – hard drives and disk controllers, connecting cables, RAM or the computer’s central processor. A sudden power outage in the absence of an uninterruptible power supply is also one of the most common causes of data loss. Depending on what was happening on the computer at the time of the failure, the consequences could be more or less severe.
Disk controller failures :
Most often, we have seen cases of Facebook data loss due to disk controller failures. At the same time, at the time of the accident, the controller was performing a write operation, which ended with errors. As a result, the system areas of the disk turned out to be destroyed, after which all or part of their data became inaccessible.
Note that the disk controllers of modern file servers, such as the Compaq Pro-liant, log hardware failures and allow diagnostics to be performed. This makes it possible to detect dangerous symptoms before they lead to failure. For example, in one company for several weeks, the disk controller wrote messages to the system log about a possible failure of the cache memory built into the controller. And when that memory finally failed, several gigabytes of important data were gone.
Computer viruses :
Almost everyone knows that computer viruses damage data. However, unfortunately, not everyone fulfills even the elementary requirements that significantly reduce the likelihood of a viral infection.
When organizing anti-virus protection, first of all, it is necessary to determine the possible ways for viruses to penetrate: floppy disks, CDs, e-mail, Web servers, etc. Then, based on this analysis, you should choose the most suitable anti-virus software by installing it on each computer in your network. In this case, it is necessary to strictly follow the recommendations given in the description of the selected antivirus. The slightest deviation – and all efforts for anti-virus protection can be reduced to zero.
It is also necessary to periodically update the anti-virus database of your program, and on the network this must be done on all servers and all workstations. The anti-virus database contains a description of the signs by which the anti-virus program searches for malicious modules. Since dozens of new viruses appear in the world every day, the task of periodically updating the anti-virus database seems to us to be very relevant.
Modern anti-virus programs “know how” to update the anti-virus program via the Internet or an intranet. This capability is especially important in large networks with hundreds of servers and thousands of workstations, where manual updates become an impossible task.