Image source: Network
We all have experience with hard drive damage. For example, multiple forced power outages, reading and writing are not normally plugged in, strongly bumped, or thundered.
When you use the computer to read and write the hard disk, it is suddenly pulled out, which may cause damage to the partition table. So in general, users know that when launching a hard disk, click the right button of the computer to "safely pop up". From a purely technical point of view, if the power is abnormally powered off, and the time may just cause the disk head to swing back after writing the data, it cannot be properly homing. If it occurs multiple times, the head will be abnormal, and there is a probability that the disk cannot be read and written normally. .
First look at the hard disk structure:
The speed of the hard disk is 5400 rpm and 7200 rpm, and the SCSI hard disk is more than 10,000 to 15,000 rpm. It is a very sophisticated device. During reading and writing, the entire disc is in a high-speed rotation state. If the power supply is suddenly cut off, the magnetic head and the disc will be violently rubbed, resulting in bad sectors or even damage to the hard disk, and the data stream will often be lost.
It is worth noting that with the increase in demand for security, etc., manufacturers such as Seagate already have professional "monitoring hard disks". Seagate has a SV35 monitor hard drive that has passed the inspection of the Ministry of Public Security and police and has passed the test. Taking the SV35 as an example, the difference between the monitoring hard disk and the ordinary hard disk is mainly reflected in the four aspects of power supply, cooling environment, data reading and writing, and working time.
The monitoring hard disk works around the clock, with an average time-to-failure time of 1 million hours. Therefore, in terms of stability and reliability, the monitoring hard disk is better; the monitoring hard disk power management is more strict, and there will be UPS power protection when the power is suddenly turned off. Compared with ordinary hard disks, the monitoring hard disk has a lower probability of being damaged due to power failure.
The basic science is finished. How difficult is it to fix a hard drive?
If it is a small white user, you can use some professional hard disk repair software. The more common one is EasyRecovery. Fu Sheng also actively promotes his hard disk repair tool on Weibo:
Or look for a professional damaged hard drive repair vendor, but this cost will be slightly more expensive.
No longer, Baidu will always be there? There are many offline hard disk repair service sites.
From a professional point of view, Tom's Hardware has introduced the whole process of repairing a hard disk. From the perspective of maintenance personnel, repairing the hard disk mainly includes the following steps:
1. The first step is to diagnose the problem. But unlike many people think, the first step for the technician is not to analyze the hard disk failure with software, but to connect it to the power supply and then listen to the operation.
The technician can notice some slight vibration and noise on the hard disk. If the noise of the hard disk is very loud at this time, they will stop operating immediately. At this stage, they will try to let the hard disk run and judge in the shortest possible time. If it is considered to be saved, it will move to the next stage.
2. After the simple check is completed, the hard disk will be connected to a test system to see if it can be started, whether it can get some value, and read and write operations. The focus of this phase is to determine who will be handed over to the SRS in the next step.
Seagate's Peter Oswald said that he had seen a hard drive that had been bitten by a dog, had been smashed by a hammer, burnt by fire, and had entered the water... a variety of problematic hard drives.
3. Many people don't know that most 3.5-inch hard drives have at least one filter. The filter was loaded into the hard drive under clean production conditions, so it was clean.
The technician can quickly know whether the magnetic head has been in contact with the surface of the disc. If there is contact, the tiny particles will splash around the hard disk, and the filter will stain the particles and change color. After removing the granules, the hard disk can be used for a longer period of time.
4. In a few cases, the detached discs need to be mounted on highly specialized machines. They can inspect the tracks in depth. Generally, the technician can change the damaged parts into good parts at this time, so that the hard disk can be more normal than before. Working, and then have the opportunity to extract data from it.
Peter Oswald said his team can use software to transmit precise positioning to the hard drive, letting it know how to read the data, but the technician still has to know and know which area of ​​the disc to position.
5. Physical and logical failures are involved in most RAID recovery requests. If replacing the parts does not solve the problem, you can use the magnetic field clone to completely copy the information in the damaged hard disk to a new hard disk without damage.
In essence, the deletion of a file under the normal system is a quick delete of the execution, that is, the file header of the file is deleted, and the actual file actually exists on the hard disk. If the data storage operation is not performed on this storage area at this time, the deleted file can be restored by software. This is why the hard drive data is deleted, or damaged and recoverable.
For small white users, the troublesome steps mentioned above are generally not used.
In Q2 2016, the major disk manufacturers have bad disk probability statistics as follows, data source Backblaze:
As can be seen from the above table, the probability that the hard disk is completely damaged is low. In recent years, security monitoring has long been a major trend in the cloud, monitoring data is too much chaos, massive data is difficult to extract, and relying on traditional hard disk storage solutions is not practical. General security monitoring has remote backup, not to mention disk arrays. Many Internet companies have cloud service backups. 360 cameras directly record and synchronize backups. The time limit for viewing videos is 7 days to 30 days.
The technical support of cloud storage and cloud computing will make the cost relatively lower and the system architecture more secure and reliable. Domestic security companies such as Hikvision and Dahua have been actively launching cloud storage solutions, but such technologies are currently playing better in smart cities and smart transportation projects.
Wenzhou Vigorous Pet Products Co.,Ltd , https://www.vigorouspet.com