Is it risky to modify dns?

DNS (Domain Name System), a distributed database on the Internet that maps domain names and IP addresses to each other, allows users to access the Internet more conveniently without having to remember IPs that can be directly read by machines. Several strings.

#The process of finally obtaining the IP address corresponding to the host name through the host name is called domain name resolution (or host name resolution). (Recommended learning:PHP video tutorial)

The DNS protocol runs on top of the UDP protocol and uses port number 53.

In the RFC document, RFC 2181 has specifications for DNS, RFC 2136 describes dynamic updates of DNS, and RFC 2308 describes reverse caching of DNS queries.

Each IP address can have a host name. The host name consists of one or more strings separated by decimal points. With the host name, don't memorize the IP address of each IP device by rote. Just remember the host name that is relatively intuitive and meaningful. This is what the DNS protocol does.

What is the impact of changing dns

DNS is the English abbreviation of domain name resolution server. On the network we usually use, we need to know the other party’s IP address data before arriving. To reach the other party, its function is to convert the domain name that is easy to remember when we surf the Internet into the corresponding IP address, so that the data you send reaches the server of the website you visit.

The DNS you fill in is the IP address of the domain resolution server. You send it the domain name, and it is responsible for converting it into an IP and sending it back to you, so that you know the IP of the website server and can access the website. . (This statement is not very standard, but it is easy to understand. If you want to know the specific principles, please check the relevant information yourself) If that’s all you have

If you change the DNS settings to a non-domain name resolution server or cannot A normally working domain name resolution server will result in the inability to open web pages, including all programs that use domain names to access. Programs that directly use IP will not be affected. This can also be one of the common computer faults that QQ cannot open web pages.

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