Why do you need a server, what types of servers are there. What is server equipment? What does a server room consist of?

Welcome to the blog site. From this article you will learn what a server is, its role and what types they are. Many of us are familiar with the concept itself, since few people can boast that when using the Internet and browsing websites, the “Server unavailable” window has never popped up.

But not everyone knows the meaning of this term, so we will try to study in as much detail as possible all the nuances regarding what a server is and what it is used for. At the same time, we will look at the types of servers and their main differences from each other.

Server concept

So, what is a web server? This is a special hardware device that allows you to perform certain tasks on the Internet. However, such installations can be used not only remotely, but also locally. They store particularly important information from firms and companies, educational and other institutions. This is only the smallest example of using a “server,” as programmers and users call it in jargon.

Meaning of the word

What does the word server mean in network technologies? If we briefly dwell on the origin of the term itself, it originates from the English verb “to serve”, which literally means “to serve”. And if we compare it with the operating principle of a modern server, we can note a close relationship.

The main purpose of the server is precisely to serve as a file storage and document storage, and as a coordinator for the operation of many systems. Even novice computer scientists know that numerous processes related to the functioning of computer equipment and websites depend on the normal operation of the server. Therefore, it is extremely important that the server computer regularly receives the necessary maintenance from specialists in the field of programming and computer technology.

Previously, servers were located directly in the “system unit” - the system unit - of desktop computers. But this was very inconvenient, since users often had to buy additional “boxes” to store all the necessary information. But at the end of 2000, everything changed, and today a server is the same computer, only more powerful. It can have the same structure as an ordinary system unit, or be formed from several other components.

Like an ordinary computer, this device works thanks to:

• powerful processor;
• motherboard;
• RAM;
• hard drive (hard drive).

Such hardware can have different sizes - it all depends on the purpose and place of its use. Its purpose also varies.

The concept of a server address

What is a server address? This is a set of symbols, letters, designations that direct the user to a specific target computer. Typically, this concept refers to the system name, but only if one specific domain works with a separate, single computer. It is noteworthy that the IP address is also a server identifier, just like a separate domain name.

Definition. In simple terms, a server is a computer designed to store files and information. In order to operate with data located on the server, it is important for the user to know that the device must be connected to the Internet and the power supply network around the clock. If we are talking about a private server, then the owner can turn it on and off when he sees fit.

Thus, in computer science, a server is a separate device, although it can be controlled using special programs through operating systems.

The role of the server and why it is needed

We briefly figured out what a computer network server is. Now let's take a closer look at what such a device is used for. The fact that you can store necessary and important information on it is no secret to anyone, but its capabilities do not end there.

So, what is a server for? This technique performs a number of important functions, including:

1. Storing data from various Internet sites, portals, resources. For example, servers are successfully used to save email and media files. The so-called “cloud” on the Internet, where users upload various data, also takes up a certain space on the server and has its own address where it can be found.
2. Ensuring and maintaining the work of Internet providers. A person who is just about to connect to the Internet, or wants to replace an Internet service provider (supplier), must know why a server is needed, because it is with him that he will deal every day. To gain access to the World Wide Web, the client must pay a certain fee. In this case, we are not talking about buying a router or Wi-Fi router. We are talking about paying for the opportunity to use the Internet provider’s server. This is nothing more than your IP address.
3. Storing materials from different websites. This can be videos, pictures, articles, folders and other content. In this case we are talking about such a concept as Internet hosting. Read more about hosting and its difference from a server at the link

Important! For normal operation of servers, specially developed server software is required. This is done by professional programmers; a simple user cannot independently provide normal maintenance of such complex equipment.

Server-client concept

Now let's look at what a server is and what a client is. We have already dealt with the first concept, now let’s look at the second. The client is the one who accesses the space on the server computer. It could be one person, or a whole company.

That is, if you have your own personal website on the Internet, then for it to work you will need a place to store all the files. When using ready-made engines for such resources, developers provide disk space - free or for a fee. In this case, the site owner is a client of the hosting company.

If the site was developed from scratch, using its own engine, and the owner has plans for the further development of this business, then he may well acquire his own server. In such a situation, the entrepreneur is not a client. On the contrary, by developing his business, he can gain a client base himself.

A client is also a person who requests a specific file through a server. The second, in turn, gets access to it and transfers it to the client. The server itself does not perform any operations with this file.

What types of servers are there?

There are many types of servers, since the developers and users themselves classify them in their own way. But speaking in general, what is most often taken into account is the gradation according to the type of problems being solved. According to this criterion, the following types of servers are distinguished:

1. A web server that helps the client obtain the requested file.
2. An application server that gives more opportunities for processing information and works on the principle of an application.
3. A dataless server that is used to conduct business transactions and process user requests.
4. A proxy server that performs 2 main functions. The first is to ensure that the user can safely obtain information from the Internet. In this case, the server operates on the principle of an intermediary. The second function is to store information in the local disk cache. This allows the user to obtain this information again without logging onto the Internet again.

This is not all in terms of the question of what types of servers there are. There are other varieties of them, but they can be called a kind of subtypes of the previously described species.

Another type you need to know about is local. A local server is a specially designed program that allows programmers to create and develop websites without necessarily accessing the Internet. Both professionals and beginners who want to connect their professional life with Internet technologies can work with such programs.

Let's figure out how a server computer differs from a regular desktop computer and what the practical challenges of buying a server computer for your home might be.

First, a little theory. What is the meaning of the term “server computer”, also known as “server”? The Latin root "serv" means "servant" and is also a key part in derived words. “Server” must be understood as a computer whose task is to provide a remote user with any set of services, and in an automatic mode, without the participation of constant control by a human operator.

You can imagine a student dormitory where guys and girls from different floors and rooms share files, Internet access, or play cooperative games with each other - on completely ordinary computers and laptops. A few network settings - and out of the blue a real server computer appears. In the simplest version, a really old computer can act as a server - we set the settings, plug in the wires and slide it under the table.

But what works for a few units or even dozens of people will not work at all on a larger scale. Three main properties distinguish server computers from ordinary ones:

1. The server must process requests from all users at the maximum level of performance.
2. The server must operate continuously, even regular reboots are extremely undesirable. In network slang, the continuity of server operation is called “uptime”.
3. It is even more undesirable to shut down the entire server if it is necessary to replace any component. The ability to not turn off the whole when replacing a particular can be called “hot plugging”.

How to understand this in practice? Let’s take Internet access—the provider provides a connection at a given speed and keeps track of traffic and payments. All this is carried out thanks to the work of server computers - and even in the simplest case we are talking about thousands of users. And all these users should calmly receive the paid set of services, and not be angry because of delays or lack of communication.

The provider's server computer provided a person with access to the Internet, but what does the latter consist of? Simplified - from sites. And these are servers again, only not from communication providers, but from hosting providers - services for creating, storing and providing website data. In some cases, many small sites will be physically located on one machine, in others, a powerful dedicated server will work in the interests of only one popular site.

Servers are not necessarily connected to the world wide web. We can mention scientific computing, where gigantic computing resources are needed, servers are popular and in many enterprises - from factories to shops, which allows for efficient accounting and control, processing many statistical queries. No ordinary personal computer can handle this.

What does the server consist of?

In technical terms, a server computer “begins” with a motherboard and a central processor. The general logic here is the same as in a regular computer. But there are also several general differences - there can be several processors on the motherboard, and there are radically more slots for connecting RAM than is customary in the most advanced personal computers.

If the top personal Intel Core i7-2600K supports up to 32 gigabytes of RAM, then the not-so-very Intel Xeon Processor X5570 is quite capable of working with 144 gigabytes! Moreover, while a desktop processor typically has two or four cores, server chips have at least ten cores. In the example given, the number of cores, by the way, is the same.

It is worth noting that while Intel and AMD are leaders in the personal computer market as a whole, IBM, HP, Oracle and Fujitsu also play a significant role in the server solutions segment. At the same time, if the x86 architecture is now popular in the personal segment, then in the server segment almost all significant market players continue to offer their own technological solutions, we can mention Intel’s IA-64, IBM’s POWER and the joint one for Oracle and Fujitsu - SPARC. This, in turn, imposes certain restrictions, since the capabilities of server software are directly related to the decisions of manufacturers.

What all manufacturers agree on is the ability of the servers to do the so-called. hardware virtualization is a very vital function, especially for website hosting - you can run several virtual machines on one server at once - and all of them will work with almost the same speed as the physical server itself.

In general, server computers are fast and powerful. But everything has its price. Server operation requires high power consumption. No one needs to waste energy on unnecessary purposes, so such familiar hardware functions as, for example, a sound controller or USB channels are simply absent in the server version. The video card is also often absent or present in an extremely limited form. As a rule, everything that needs to be initially configured or seen by the server operator can be done via the command line - no fancy video card is required for this.

Eight megabytes of video memory for a server is normal; the amount of RAM is much more important. It's not just a matter of striving for perfection, when an engineer wants to insert memory into a slot, since there is already a slot. The problem is that modern hard drives have not yet crossed the threshold of several terabytes; to obtain large volumes, they are combined into so-called. RAID arrays, but this entire set of hard drives still needs to be physically spun (how do you like a speed of 10 thousand rpm?) and read, while RAM allows you to temporarily store quite large amounts of data to speed up access.

Types of servers

Externally, server computers come in two types - tower and rack-mount. The tower version, also known as a “box,” can have practically the same dimensions as a personal computer; its body is made of durable solid steel, the task of which is to absorb vibrations and noise.

On a practical scale, the more common option is rack servers - computers are installed in special mounting cabinets, which themselves stand in a special room - the server room. The rack-mount version looks like a drawer from a desk or a large car radio.

When setting up rack servers, you need to deal not only with power supply and noise reduction, but also with cooling. It comes to the point that server operators work in server rooms in winter clothes, because if you turn off the air conditioning, the servers will very quickly overheat and begin to collapse. On the other hand, a server rack is easy to expand - a new server can simply be purchased and installed in the mounting cabinet as needed, this is “hot plugging”.

As for the operators and the command line, which is enough to configure the server, this is indeed the case - unlike the operating system market for personal computers, where Microsoft solutions are leading, the server software market is dominated by UNIX-like systems, in other words, Linux . And these operating systems, even in their personal version, until recently, were not very keen on graphical interfaces.

In addition to the operating system, of course, other necessary applications can be installed, depending on what tasks the computer faces.

How to replace the server?

Thus, we can come to the following: if you need to get new shades of pleasure from a computer game or multimedia, or distribute your files to all your housemates, then you should not buy a server computer for this.

Just a good model of a modern personal computer is enough. If you have some scientific or business tasks that require significant calculations and volumes of data, then even in this case, operating a server computer at home will not be a very sound idea - your electricity bills will increase, and costs for operator services will appear -administrator (you still need to configure and check), you will also need to re-equip almost the entire room, putting it under the control of computer hardware.

It is perhaps better to use the services of remote cloud services and server data centers, the capacities of which you can access from a regular desktop computer, and specialists will take care of all the setup and maintenance. But if your desire is still strong - you need your own server and that’s it, then maybe it’s time for you to simply create your own data center?

Using server equipment, data is securely exchanged, stored and updated within one company. The main tasks of servers are storing information, protecting against information loss, and processing data.

What is the equipment?

Server equipment is a hardware complex that, depending on the scope of construction and architecture of application, includes server and network devices with various characteristics. It is located in a specialized dedicated place (rooms), called a server room.”

Modern hardware of the company is placed in server cabinets for ease of installation and saving space. These cabinets are equipped with devices from leading industry manufacturers.

For example, Dell's technological equipment is a modular concept for assembling servers. If a server component fails, it can be easily replaced with a similar or upgraded component.

There are tower and rack-mount enclosures, with different height (width) sizes.

For example compact

Looking under the cover of the case, you can find a familiar arrangement of server components.

The cases of personal computers and servers are in many ways similar to each other, but the equipment installed in them solves different problems. A computer is the tasks of its users. Server – tasks for hundreds and thousands of connected subscribers 24/7.

Installation

Ready-made hardware solutions are installed separately or in a specialized cabinet (or rack), which compactly accommodates several servers in a specific case.

Additionally, the furniture is equipped with small doors made of glass or plastic, allowing access to parts of the system.

Racks can be supplemented with:

cooling system;

power distributors;

LED indicators.

In addition to rack-mount enclosures, server mounting can be carried out on the ceiling or on a table. It depends on the allocated space and the wishes of the customer. Installation, commissioning and software configuration are entrusted to professionals. The same applies to network equipment, which is connected with patch cords to each hardware device, and through network equipment is connected via communication channels to the global network.

In today's article, dear reader, we will talk about servers and server equipment what they are and what they might be useful for.

A server is specialized hardware equipment that is designed to perform special service tasks on it.

Most often, a server is a computer that is separated from a group of other personal computers or workstations, designed to perform various service, distributed and other tasks on it without direct manual control by a person. In principle, almost any computer can act as a server, but usually a more powerful machine is allocated for server purposes. We will talk about the reasons for this below.

A human is ideally required only for the initial installation of the server software and its initial and basic configuration, after which it should operate in an automatic mode. But in reality, all this is a little different, and companies have to maintain a full-time system administrator, one of whose main responsibilities is the maintenance and configuration of servers and server equipment.
Servers usually do not require a monitor, keyboard and mouse; they are usually configured and maintained via a network interface. But if the network settings are reset, and the system administrator does not have access to the server, then, of course, you need to connect peripherals to it and only then see what happened to it.

Server equipment is mainly designed to perform certain tasks in a “all year round, seven days a week, 24 hours a day” mode, so it is important to ensure the uninterruption of this very work. To save and duplicate information, RAID arrays of hard drives are used; the server motherboards themselves and other components are installed in special cases with built-in air conditioners to maintain a certain optimal temperature. Network equipment is placed in communication cabinets specially adapted for this purpose. There is no need to talk about uninterruptible power supply systems - they are designed in such a way that the server operates even in the most extreme conditions with power supply, and so that its safety margin and reliability ensure this uninterrupted operation until industrial power is supplied. To accommodate server equipment, a special room is usually allocated, which is called a server room.

To meet all these requirements, designers of servers and server equipment are creating special solutions in the form of multiprocessor motherboards, processors specially adapted for performing server tasks, RAM modules with enhanced error correction technology, racks for hard drives with the possibility of being “hot” swappable. And it is often possible to “hot” replace not only individual hard drives or even their arrays, but also other components – right down to processors and RAM modules. In ordinary workstations this is impossible by definition, isn’t it? Monitoring parameters should also be at their best - fan arrays, temperature and cooler speed sensors, additional power supplies - all this is required for normal operation server equipment.

Of course, all this server equipment is by no means cheap, but believe me. Ultimately, it is completely justified.

Servers that require high performance are usually installed in special racks and cabinets, which are supplied by manufacturers with mounting parts. If high server performance is not required, then this equipment can be significantly reduced in size. It is then usually placed in a simple system case.

In the industrial design of servers, the housings have increased strength, are equipped with additional filters to protect the insides from dust, and the control buttons are designed in such a way that they cannot be pressed accidentally.

The servers run on the desktop. Floor-mounted, ceiling-mounted and rack-mounted versions. The maximum level of scalability and the highest level of placement density is provided, as you yourself understand, by the ceiling option.

In terms of resource use, servers are specialized in two completely opposite directions - reducing resources and increasing them. Reducing resources aims to minimize the size, power consumption and other characteristics of the server. Increasing them involves an all-out increase in capacity (for example, the computing power of processors, their number, installation of new hard drive controllers, etc.). When it is no longer possible to increase capacity further for technical reasons, then another server is installed, and part of the functions of the old one is transferred to it, and so on until all resources are used.

Hardware solutions are the highest level of specialization of server equipment. Such solutions include hardware routers, routers, network disk arrays, and terminals. For this equipment, specialized software is used, which is loaded into their non-volatile or permanent memory already at the stage of their manufacture by the manufacturer. Nobody argues that hardware solutions are more stable in operation than conventional servers, but at the same time they are much less flexible and universal. They can be either cheaper or significantly more expensive than conventional servers. This factor depends on the manufacturer and class of the equipment itself.

Recently, pseudo-hardware solutions based on x86-compatible computers have appeared on the market. These are basically diskless servers assembled in the mini-ITX form factor and positioned as hardware solutions, which they actually are not.

Well, now it’s time to summarize and comprehend all of the above in relation to servers and server equipment.

1. A server is equipment made to perform service tasks. He performs these tasks as much as possible without human instruction.

2. Peripheral devices, such as a mouse, keyboard, monitor, are not used in servers at the stage of their constant operation. They are required only for initial operation and server configuration by system administrators.

3. Server equipment operates under special conditions - 24 hours a day, 7 days a week, 365 days a year. Therefore, they are equipped with more expensive components: processors, memory, hard drive array controllers, etc.

4. In order to increase the reliability of the server, if possible, it will be equipped with components that can be replaced even “hot”, that is, when the computer is turned on, without disconnecting it from the network.

5. In the server room - the room where the company’s servers are located, a special temperature regime is usually set and additional temperature sensors for disks, processors, memory, etc. are installed.

6. The one who maintains and configures the servers is called a system administrator (most often this is a guy or man with a beard and glasses who really likes beer).

7. Recently, the so-called blade servers have been developing and becoming widespread - server solutions that are based on the lowest possible consumption of resources and the space they occupy. Such devices are usually placed in one rack to save space. Saving space and energy consumption does not mean reducing productivity.

That's all for the servers. Of course, you don’t need such a thing at home, but of course you need to know about them.

A server is a certain program, device or software and hardware complex that implements some services. In turn, a service is a service that performs certain actions requested by the client. Let's take a closer look at how the server works.

Components of a client-server scheme

Let's see what the server itself consists of and what external components it cannot do without. Firstly, the server loses its meaning in the absence of clients. The principle of the server is to fulfill the needs of clients. The client forms requirements for the server and takes on a certain share of its work. Therefore, they often talk not just about the server, but about the client-server system. The client makes requests to the server, through which he expresses his will. Therefore, the next, second component of the system will be the formal language in which these requests are compiled. There are a great variety of these languages ​​and the choice of one or another directly depends on the server. Requests to the server must be delivered somehow. The third element is the communication channel between the client and the server through which data is transmitted. This is most often either a local network, or the Internet, or local connections of one machine. The server must somehow accept and recognize the incoming request. The receiving device - the so-called external interface, consists of several ports that the server continuously (or not continuously) listens to. Accepted requests are sent to the software part of the server, where they are processed in accordance with how the server is programmed. And depending on the received request, one or another service is launched with one or another initial data. Services will be the last component of the system. After the service is completed, the execution result is sent to the client via the same communication channel. Or, if the service is interactive, then during its operation there will be intensive data exchange via the client-server channel.

What is the server for?

Now the main purpose of client-server systems is to move the load from client machines to the server machine. That is why the computing power of a regular server is a couple of orders of magnitude higher than that of a regular home computer. But sometimes this organization of the system transfers the entire load to the clients, and the server serves to organize their work and interaction. Or strictly vice versa, the server performs all the calculations, and the clients serve only to provide information to the user. As you can see, there are a lot of ways to use the client-server model.

Pros and cons of the model

The advantages are obvious - the very principle of the server’s operation ensures ease of use of the system, ease of management, and proper distribution of the load on the machines. The downside is the query language and related components. If a user accidentally or intentionally sends an incorrectly formulated request to the server, then if such an error was not foreseen by the programmer, the system will crash. Knowledgeable people make deliberately incorrect requests so that the system designed to provide a client with a weather forecast will display to the attacker, for example, the credit card data of all users (if, of course, the same server is responsible for the card data and the weather forecast). And the happy attacker first goes and transfers to himself all the money of all users of the service, and then for a long time and thoughtfully runs away from the “K” department, which is investigating this crime.

Safety

The client-server model of organizing the operation of the system is a very convenient thing to program, manage and operate. But in order for such a system to be used, each component of a working circuit must be protected both from intruders and from users who do not know how the server works, but press all the buttons that they can reach in any order. In order for the system to store, transmit and process important data, for example, information about payment cards, the server’s information security system must meet certain legal requirements.