A hard drive is an integral part of a computer. The component has not yet been replaced with new products. Its closest competitor, SSD, is so far only an assistant in the system, since it has an extremely high cost. Rail purchased for installation in home PCs, gaming systems and server. The choice of HDD for the latter option is not easy.
About discs
A hard disk, aka a hard disk drive, is a device that has random access to stored information. This version of the mechanism is based on magnetic recording.
All necessary data on the HDD is recorded on aluminum or glass plates. They are coated with ferromagnetic material, sometimes chromium dioxide. The necessary data is collected using a special head. In order for the railway lifespan to be long, the head does not come in contact with the surface of the magnetic disk. The work is due to the oncoming flow of air, which is formed using the rapid rotation of the mechanisms.
Complex systems
Before you consider the hard drives for the server, you need to decide on the concept of "server". This is equipment that is usually represented by a specialized computer or specialized device. It is designed to run service software.
The hard disk for the server is usually used in a dedicated computer - a server that stands out from the varieties of computers. It is designed to perform service tasks without the direct participation of a person in this process.
The server in this case is similar to a workstation, but differs from it in the degree of human participation at the console.
What is needed for the server?
Since the tasks of these computers are different from those that set in front of home PCs, their design is somewhat different. For example, the memory should have enhanced error correction technology. This is necessary in order to quickly cope with possible failures.
Server reliability is affected by redundancy, which supports hot-plugging and replacing important system elements. To do this, you need to acquire server hard drives, which are usually part of a RAID array. Fast replacement of the power supply and ensuring duplication of processors is also important. It is equally important to quickly replace fans and other cooling systems in the event of a breakdown.
The server also requires hardware monitoring. It helps to constantly monitor sensors, set special modes for processors, memory modules. It is important to check the temperature in the bays with server hard drives, etc.
What to look for when choosing?
In the question of which hard drive to choose for the server, several points are important. Buyers usually set themselves the following factors:
- reliability;
- performance;
- response time.
This may also include the cost of the devices and their manufacturer. Otherwise, the above three factors are extremely important for the overall server performance. Reliability ensures uninterrupted operation of mechanisms. Otherwise, irreparable data loss can significantly affect the company's losses and reputation.
Performance helps speed up overall server performance. For specialized computers it is extremely important to quickly read numerous commands. Response time directly affects performance. If the hard drive wakes up slowly, there may be problems with request processing.
Disc Categories
Considering the hard drives for servers, you can pay attention to several categories. These are SATA, SATA RAID Edition, SAS Near Line and SAS Enterprise. Of course, in addition to this, there is the option of SSD, SAS SSD, etc. But SSDs should still be assigned to a different group, since they differ markedly from their HDD characteristics.
So, SATA is the most common variant of devices that are used in ordinary PCs. Their speed is enough for everyday tasks. The maximum value is 7200 rpm. SATA RAID Edition is practically no different from the previous version. The only difference is that the latter supports RAID controller commands.
SAS Near Line has a frequency of 7200 rpm, but is connected via a different interface. But SAS Enterprise operates at increased frequencies from 10,000 to 15,000 rpm.
Connection interfaces
The hard drive for the server can almost never connect via SATA. This interface has been redesigned with the IDE. It is focused on the work of household computers and some industrial systems that do not need serious reliability requirements.
SAS is designed to connect a server device, since it was developed from the previously popular SCSI interface, which was also used for this task. The main advantage of this type of connection was that it had high bandwidth. But soon the third generation SATA was also able to achieve high results.
Only after some time, the SAS controllers were able to work with a throughput of 12 Gb / s. This interface is backward compatible with SATA.
Interface Features
The SAS hard drive for the server works with full duplex data exchange. The HDD can simultaneously read and write, while SATA can handle one of the commands. To realize this advantage of a server hard drive, you need to connect a large number of drives.
Why is SATA not suitable for the server?
There are several reasons for this:
- Instability to vibrations.
- Unrecoverable errors.
- Lack of hardware RAID controllers.
All three factors do not allow users to use ordinary hard drives for the server. And even the fact that the cost of SATA is much lower than that of SAS does not affect the choice. In this case, the buyer is much more important high performance, security and speed of access to data.
Manufacturers
One of the main factors in choosing a product is the manufacturer. Hard drives are a popular product, so it is easy to find it on the market. Things are more difficult with the choice, since it is really very large.
Of course, many people know that cool brands almost never produce hard drives. For example, HP or DELL only produce hard drives, buying them from third-party manufacturers. Therefore, the choice may not always depend on the eminent seller.
Such companies provide firmware for the device, studying carefully the features of the controllers. They also conduct additional quality control using stress tests. So that the buyer is not offended, the seller provides a guarantee and support.
As a result, the so-called "native" drives are several times more expensive. Moreover, such an increase in prices is not always justified. And, it would seem, it is much more profitable to give preference to the manufacturers themselves.
But when working with the server, users heard many stories that non-native devices fail, and the adaptation of the HDD from the same HP or DELL helps to stabilize the work.
Principle of work and choice
When trying to figure out how much a hard drive costs for a server, one key point should be taken into account: servers often use special technologies that affect the performance of the disk subsystem. Therefore, companies are reflashing ready-made railways to cope with the given technologies.
The cost is also affected by the fact that some vendors specifically forced customers to purchase "native" models, otherwise they blocked some features of the devices. As a result, the buyer could buy a hard drive cheaper, but it would not work at the proper level.
And yet you should not go on about the vendors. Now many "non-native" railways cope with the work in servers. It is necessary to check compatibility with the slide and the generation of equipment.
As practice shows, many vendors use only a couple of models and popular rulers. Therefore, the buyer will definitely encounter railway from Seagate Enterprise Capacity or Toshiba AL13SEB.
Of course, to say which of the manufacturers is the best is not easy. But, as statistics show, the most reliable models are devices from Hitachi, WD and Seagate.
Overview of some models
The SATA hard drive for the server is no good, so the choice must be stopped on a device with a SAS interface. In addition, SATA drives are usually selected according to standard characteristics such as volume, spindle speed, plate capacity, etc. When choosing a server device, you should pay attention to optimizing the firmware, as well as the ratio of performance to power consumption.
Seagate introduces several lines that have spread to the SAS and SATA drives segment. Both groups are also divided into 3.5 and 2.5 inch models. Railways are very similar to each other, so in some cases only the amount of storage affects the choice.
Among the 3.5-inch SAS, there are two series of devices: Cheetah and Constellation. The first include three models of 300, 450 and 600 GB. All of them work with a throughput of 6 Gbps and 15,000 rpm.
Among the Constellation models, there is a hard drive for a 1 TB server. There are also models for 2, 3 and 4 TB. Devices work with the same throughput and 7200 rpm.
Among the 2.5-inch SASs, there are also two series: Savvio and Constellation. The first line includes models operating at a frequency of 15,000 and 10,000 rpm. However, they have a small amount of storage. But those hard drives that operate with an indicator of 7200 rpm are presented in versions of 500 GB and 1 TB.
Similar models can be found at the manufacturer Western Digital, HGST, etc. They practically do not differ from those described above. The difference can only be in price.
How much does a hard drive cost?
As already mentioned, depending on the manufacturer, the price of the device may be different. For example, the Hitachi company sells a 1.2 TB model for 20-24 thousand rubles. While the model from HP at 1 TB can be purchased for 30 thousand rubles.
The cost is affected not only by the manufacturer of the hard drive, but also by the volume of its storage. For example, Seagate 300 GB will cost only 8-9 thousand rubles. But the model from the same manufacturer, but at 12 TB will cost about 40 thousand rubles.
By the way, in the store it will not be easy to find an external hard drive for the server, because these devices use different technology and do not need hard drives of this type.
Note
Drive selection is based on the tasks that the server must perform. For example, if high-speed access and reliability of archiving are not so important, then you can look at SATA models. This option will be cheaper.
If the array should have more than 5 disks, then it is better to select SAS NL models. This option is suitable for medium-sized systems where it is not necessary to provide a high load or a huge amount of data for processing.
For the most productive tasks, which require fast work and reliability, SAS Enterprise models are suitable. These media can function for servers with high load and with a huge number of users.