What is a server?
The Bengali meaning of the word Server is distributor. That is, the one who serves is called a server. In the language of computer science, a server is a computer where data or information is stored. We can also compare it with a storage device. A normal computer and a server computer are two different things.
Because the real purpose of creating a server is so that data can be easily exchanged with other computers. Which is very difficult and difficult to do through a network with a normal or personal computer. All servers are computers but not all computers are servers. The main reason for this is the hardware and software configuration.
When creating a server, more powerful hardware is used than a computer. Which helps in storing unlimited data on the server and keeping it active 24/7. Apart from storing information, another major job of the server is to handle requests.
For example, whenever you entered the link to read this article, the browser sent a request to open the file to the server. From processing the sent request to sending the specific file back to the browser, all the work has to be done very accurately by the server within a short time.
In short, a server is a software that allows a computer to exchange files over the network. It stores files itself so that any computer connected to the network can download or modify files as needed.
How does a server work?
Before knowing how a server works, we need to know what a server is made of. Mainly, one or more computers will be needed to create and operate a server. That is, to create a server, we will need power, processor, RAM and many hard drives.
Power will be needed to keep the full system running so that the server never shuts down. Processor and RAM will be needed to manage the requests coming to the server and exchange files. Finally, a storage drive as needed. Whether it is SSD or HDD as a storage drive, all of them must be running.
We have already got an idea about the server. Now to understand how the server works, we need to have an idea about the client. The client is the device that uses the network as a medium and requests data from the server. For example, a web browser is a client.
The server works in the Request-Response Cycle process. That is, suppose you search for information about a mobile on Google. Now the web browser will send a request to Google’s web server as a client for that data. Google’s server receives the request and processes it with the processor to see where that information is on their storage drive. As soon as it is found, Google’s server will send the search data to the client software or web browser. Then you can see that data in front of your eyes.
Simply put:-
- First, we need to enter the URL (Uniform Resource Locator) of the website or file in the client software or browser. The browser then takes the data from the URL and requests it to the DNS (Domain Name Server).
- Then the DNS server finds the IP of the URL in the entire world-wide WEB server.
- After getting the IP, the DNS server sends it back to the browser.
- The browser then sends an HTTP/HTTPS request to the IP address obtained from the DNS server.
- The request is processed by the server and returned to the browser. The browser then receives the files and renders them with the help of DOM (Document Object Model) interpreter, CSS interpreter, JIT (Just in Time) compiler. When the rendering is complete, it displays them on the monitor or display.
And this entire task will be done by the server software setup on the server which helps a computer to become a server.
What are the types of servers?
Servers are classified based on their usage. Let’s get an idea of the servers or server ideas that are popular today.
Web Server
The most popular server today is the web server. We know web servers as web hosting or hosting servers. The main function of web servers is to store all the files of various websites such as audio, video, images, text, etc.
All the data on the internet is stored on some web server. All the web servers are connected to each other using the HTTP/HTTPS network protocol through Apache, Nginx software. And these connected web servers have created the internet together.
We can now collect and modify any file from the web server using any client software.
Types of web servers
- Shared Hosting: In shared hosting, a single server is divided among many users. In this, all the hardware and software resources (processor, RAM, hard disk/SSD) of the server have to be used together.
- Dedicated Hosting: On the other hand, dedicated server means the opportunity to use an entire individual server. That is, you will be given an entire server, all the resources of which you will use alone.
Application Server
All the apps on your current mobile are hosted on some application server. The main purpose of creating an application server is to keep the software or applications always active and all the application data stored.
For example, the text, audio or video that you exchange while talking on WhatsApp or Messenger is stored on the server of that app. That is why all your SMS are stored for years if you do not delete them.
Email Server
The emails that we exchange using Gmail are processed by Google’s dedicated email server. Email servers are usually configured for all email tasks. When you take a web hosting, you are given an email server separately along with the main space.
Some of the popular email servers of today such as Gmail, Outlook, iCloud, etc. provide pre-configured services. Apart from this, you can configure and use your own email server.
Types of email servers
- Incoming Mail Server: Incoming Mail Server is used to receive and store mail where POP3 and IMAP protocols are used.
- Outgoing Mail Server: Outgoing Mail Server is responsible for sending each mail correctly to the sender. Outgoing Mail Server performs its work using SMTP protocol.
FTP Server
FTP Server is a popular file transfer server system. File Transfer Protocol is a standard data exchange process. All the files that are downloaded or shared on the Internet are done through FTP servers.
FTP servers use SSL/TLS security to transfer files. In this, files are transferred securely from one server to another. Many of you use broadband internet. You will notice that your ISP will give you a BDIX FTP server from which you can download all types of files at high speed.
You can even manage files on your hard disk from any place or device by making your own computer an FTP server.
Database Server
Database Server is a very large server system like a web server. Basically, all the data of a website or application is stored in the database server. These servers store user information such as payment history, username, password, e-mail, inventory, etc.
The biggest example of a database server is the result sheet of public exams. Every year, the exam results of millions of students are stored in the database server. On the other hand, every website or app is connected to the database. The largest and most popular database software of the present time is MongoDB and MySQL where all the data is stored in the form of tables.
Proxy Server
Proxy servers are created by creating personal gateways instead of using traditional internet gateways. In this, you can use many services that are difficult to use from your area.
That is, if you have any problem with your gateway while using the internet, then you can solve this problem by using a proxy server.
Local Server
Local Server is when server software is installed on a desktop computer, then that computer will act as a local server. That is, if you have 10 computers in your office and each one has a server setup, then each computer is a local server.
Client Server
Client Server is a server system with many functions. Because a client server is made up of several dedicated servers. That is, when several dedicated servers are connected together to create a network and connect to a client computer, it is called a client server.
For example, in large offices, you will see a client server created using Local Area Network. Then it handles all types of file transfers, printing and other things in the office.
Why does the server go down?
Server down means that for some reason the server is not responding or the service on the server cannot be accessed. There can be many reasons for the server to be down. They are described below in stages.
Hardware Error
We know that a server is made up of hardware and software. Especially to keep a server up and running, we need very high-quality hardware. Different hardware companies make special hardware such as processors, RAM, hard disks/SSDs to make servers.
Now, if there is a problem in any of the main hardware during server operation, the entire server will crash and go down. Because when the server is set up, it has to be careful that it runs 24/7 without any problems. That is why if the hardware has a problem, the server stops working.
The biggest solution to the server down problem is to keep a backup on the cloud server. Whenever there is a problem with it, if you restore the backup immediately, the server will be active and will never go down.
Software Error
Just as hardware is needed to create a server, software is also needed. But if the server software is not kept updated all the time, it can freeze or cause other problems. If the software does not work, the entire server system will not work.
In this, no files stored on the server can be accessed. All the services hosted will become useless. So if there is any such software issue, the server will be down. For this reason, the server-related software must always be kept up to date.
Man-made errors
Management of each server requires human help along with other resources. Now, if an inexperienced person who does not have the proper knowledge or experience in managing a server leaves the server in the hands of such a person, there is a high chance of making mistakes.
That is, to prevent server down, the server must be maintained by an experienced person. Otherwise, due to one of his mistakes, the entire server room can stop working.
Network problems
Servers are connected to each other through the network. Now if for some reason the router or internet cable gets damaged or malfunctions then the servers will not be connected to each other.
In this the servers will not be accessible from the internet. Due to which the server down problem will occur. Due to this, the server needs a network to operate and even if there is a power loss, the server will be down.
Cyber Attack
There is a hacking attack called DDoS which is mainly done to bring down the server. In this attack, a large number of fake HTTP/HTTPs requests are sent to the server. Many times the server becomes busy and unstable due to processing many requests at once, resulting in the server being down. To solve this problem, it is necessary to increase the server resources in addition to using a cloud server.
Having a clear idea about the server is very important. Because if you want to manage your own website, you must have knowledge about the server. Or if you want to create any internet-related service or do this related business, you need to know how the server works.