Failure of hard drives in video surveillance systems

If all the rest was learned to be done quite reliably and it is long-lasting, or problems come to light on the first days of operation, then the magnetic drive can fail at any most inopportune moment. Of course, it is not necessary to think of any global general pattern – at all is not present, but since this factor is the most frequent, let and not in such and negative statistics, it is necessary to talk about it. And better and to prevent it.

Alas, today's hard drives most of all other in the computer are subject to wear. And most of all they wear out in the conditions of massed (multistream volume) record and permanent rewriting which accompany the modern systems of video data recording. Emergence of BAD clusters, change of the BIOS mode, failure of mechanics – here the most widespread problems which it is necessary to face. Less lethal also are added to them: a meeting of the file system, loss of the table of arrangement of files, accumulation of temporary files (eventually resulting in impossibility of record), the fragmentation (bringing to writing rate loss that also conducts to data loss which does not manage to register in a disk), etc.

Time of failure depends on the mass of factors: qualities of technology, quality of assembly, time of operation, intensity of record, temperature condition of operation, frequency of restarts, influences of emergency shutdowns on a power supply, impurities of surrounding space, etc. – generally to foresee even year of failure impracticablly. Unfortunately (we will repeat again – though it is not so frequent), the whole series of faulty disks about which problems only modest notes are written in the Internet and only upon termination of their sales are brought to market. Cases and cross impact of third-party programs are frequent. For example, antiviruses with ease can intercept any write processes. And software of uninterruptible power supplies sins with absolutely unclear interruptions.

For the majority of scopes of computers this problem is not critical since it is easy to purchase the hard drive in any computer shop though plaints of users concerning irrevocably lost data, of course, are often heard. But for the last factor thought up prevention in the form of backup and mirroring of disks long ago. Being guided by the general practice, many developers of security systems also do not deal with this problem.

The special lab too a progressive tense did not penetrate into its importance. The previous versions of GOAL were developed by the classical principle: gave a command to the operating system to write a frame – and forgot about it. It should be noted also complexity of any other work in this direction. Windows saves data on a disk on the internal, in few places described program. And, there can pass several tens of seconds from a command to write until real preserving on the magnetic drive. And can happen and so that record will not happen in a type of failures of file structure or electronic operation modes of a disk at all. But Spetslab in the market 14 years, naturally, that from hundreds of thousands of clients there were several dozens of those, who had fatal problems of lack of record in dangerous moments of life.

After all we deal with security, and the possibility, an unpredictable possibility of failure of the archive storage which price can be estimated by lives sets thinking developers. And therefore in Spetslab: GOALcity Pegal is built-in the whole module of control of technical condition both the program, and all operating system in general. One of its functions is the control system of physical disk writing. GOALcity not only digitizes video, sends a command for record to Windows, but also checks each frame for its actual existence on a disk.

It is enough to occur to any failure as GOALcity makes the whole complex of the actions directed to resuscitation of a disk. If the problem is not fixed automatically, it is right there highlighted in windows of video cameras from which video did not manage to be recorded.

Besides, the SL language ++ allows to trace similar statuses and to make various actions:

• Notify a sound of the internal loudspeaker of the system unit.
• Say the message on external loudspeakers of the computer.
• Start any program on the computer, for example, of the recovery utility of disks.
• Execute an internal command of the GOALcity system.
• Send the message to E-mail or by the SMS.
• In the presence of the system of a call-back to call by phone to the technician or (and) to the owner.

Thus, CITY can correct or announce a technical issue before it becomes criminal.

The logic of SL ++ can be configured so that she will warn you even at the first emergence of BAD clusters. And surely it it is necessary to include on lack of record for any reasons which even organizational can enter. For example, physical shutdown removable (or even fixed) a disk is a common cause of lack of record too.

As a matter of fact, at the same time it is possible even to turn off all other standard checks of type of existence of video signal, contact with the network device, qualities of contacts and other. All the same final criterion of passing of data is the fact of record of the video frame. It also should be used for the notification. And the others - only for identification of a problem.