What does domain name resolution mean? Detailed explanation of the principle and function of domain name resolution

in the process of building and operating a website, many beginners will encounter the problem that they cannot access the website after registering the domain name, which is often closely related to the domain name resolution link. As the core technology connecting the domain name and the server, domain name resolution is the basic guarantee for the normal access of the website, but many people know little about its principle and function. This article will comprehensively dismantle the relevant knowledge of domain name resolution from the basic definition, operation logic, core value and other dimensions to help you clarify the key logic and solve the basic technical problems of website access.

What is domain name resolution?

to understand the role of domain name resolution, we must first clarify its basic definition, which is the core premise of mastering subsequent content.

1, the basic definition of domain name resolution

domain name resolution is the process of converting an easy-to-remember domain name into an Internet Protocol Address that can be recognized by a computer. Since servers in the Internet are located through the Internet Protocol Address, but the Internet Protocol Address consists of a string of numbers and is difficult to remember, so the domain name came into being. Domain name resolution is equivalent to a "translator", which translates the domain name entered by the user into the corresponding Internet Protocol Address, allowing the browser to find the corresponding server.

2, the core role of domain name resolution

domain name resolution is inseparable from the support of DNS servers. DNS servers are divided into four categories: root domain name server, top-level domain server, authoritative domain name server and local recursive server. Among them, the local recursive server is the most contacted by users. It will replace the user to initiate a query to other levels of DNS servers, and finally return the corresponding Internet Protocol Address to complete the core action of domain name resolution.

What is the operating principle of domain name resolution?

understand the basic definition of domain name resolution, the next step is to disassemble how it works, which is the key to understanding the core value of domain name resolution.

1, the complete query process of domain name resolution

when the user enters the domain name in the browser, the local recursive server will first check whether there is a corresponding Internet Protocol Address in its cache, and if so, return directly; if not, it will initiate a query to the root domain name server, and the root domain name server returns the address of the top-level domain server, and then the local recursive server queries the top-level domain server to obtain the address of the authoritative domain name server, and finally queries the corresponding Internet Protocol Address to the authoritative domain name server to complete the domain name resolution.

2, caching mechanism for domain name resolution

In order to improve the efficiency of domain name resolution, DNS servers at all levels will set up a caching mechanism. When a domain name resolution is completed, the query result will be stored in the cache of the corresponding server. Within the valid period of the cache, when the same domain name is queried again, the Internet Protocol Address in the cache will be directly returned. There is no need to repeatedly initiate multi-level queries, which greatly shortens the time consumption of domain name resolution.

What are the core functions of domain name resolution?

as the basic link of website access, the role of domain name resolution runs through the whole process of website operation, and is the core guarantee for the normal operation of the website.

1, to achieve normal access to the website

this is the most basic and most important role of domain name resolution, if there is no domain name resolution, the domain name entered by the user cannot be converted into the Internet Protocol Address of the server, the browser cannot locate the corresponding website server, and naturally cannot access the website. Only by completing the domain name resolution can the user open the website content smoothly through the easy-to-remember domain name.

2, support website load balancing

for websites with a large number of visits, multiple servers are usually deployed to share the traffic. Domain name resolution can configure polling, weighted polling and other rules to assign user requests to different servers to avoid excessive load on a single server, improve the access speed and stability of the website, and ensure the user experience in high traffic scenarios.

3. Realize the failover of the website

domain name resolution also supports failover function. When a server fails and cannot provide services normally, domain name resolution can automatically switch the request to other normal running servers, reduce the downtime of the website, improve the availability of the website, and avoid server failure to bring bad experience to users.

4. The basic operation process of domain name resolution?

master the principle and function of domain name resolution, understanding its basic operation process can help you actually complete the configuration of domain name resolution.

1 Choose the right DNS server

first to choose the right DNS server for the domain name, you can use the default DNS server provided by the domain name registrar, or you can choose a third-party public DNS server, such as Alibaba Cloud DNS, Tencent Cloud DNS, etc. Third-party public DNS servers usually have faster resolution speed and higher stability, which can improve the efficiency of domain name resolution.

2. Add the record type of domain name resolution

common domain name resolution record types are A records, CNAME records, MX records, etc. A records are used to point domain names to IPv4 addresses and are the most commonly used record types; CNAME records are used to point domain names to another domain name, suitable for scenarios where multiple subdomains need to be configured; MX records are used to configure mailbox services to ensure that emails can be sent and received normally.

3, wait for the domain name resolution to take effect

the configuration of domain name resolution, you need to wait for the record to take effect. This process usually takes a few minutes to a few hours, depending on the cache refresh time of the DNS server. You can check whether the domain name has been successfully resolved to the corresponding Internet Protocol Address through the ping command or the online domain name resolution query tool.

To sum up, domain name resolution is the core technology of connecting domain names and servers. From the basic definition to the operating principle, to the core role and operation process, each link is related to the normal access of the website. Through the explanation of this article, I believe that everyone has a comprehensive understanding of domain name resolution. Mastering this knowledge can not only solve the basic problems of website access, but also provide technical support for optimizing website performance and improving user experience.