How nginx works

How nginx works


Problem:
1. What is DNS resolution? Step 1 is briefly described.
2. Briefly describe how to establish a TCP connection with the server.
3. Briefly describe how the client and server transmit data.
4. Relationship between Http and TCP.
5. Briefly describe the Http get request process and give an example.
6. Briefly describe the Http post request process and give an example.
7. What is nginx?
8. Briefly describe the nginx workflow.
9. Fill in the content in the figure.
Answer:
1. What is DNS resolution? Step 1 is briefly described.

DNS (Domain Name System) is a distributed database that maps Domain names and IP addresses on the Internet, allowing users to access the Internet more conveniently, instead of remembering the number of IP address strings that can be directly read by machines. The process of obtaining the IP address corresponding to the host name through the host name is called domain name resolution (or host name resolution ). The DNS protocol runs on the UDP protocol and uses the port number 53.
A domain name is a dedicated address translation system for convenience of memory. to access a server on the internet, it must be implemented through IP addresses, domain name resolution is the process of re-converting a domain name to an IP address. A domain name corresponds to an IP address, and an IP address can correspond to multiple domain names. Therefore, multiple domain names can be resolved to one IP address at the same time. Domain name resolution needs to be completed by a dedicated domain name resolution server (DNS.
For example, a domain name is :***. com. If you want to access the website, you must first resolve it to a fixed IP address of a WEB server at the domain name registrar through a dedicated DNS server: 211.214.1. * **. Then, use the WEB server to receive the domain name and ***. the com domain name is mapped to this server. Enter the ***. com domain name to access the website content. This completes the domain name resolution process;
People are used to memorizing domain names, but machines only recognize IP addresses. Domain Names correspond to IP addresses. The conversion between them is called domain name resolution, domain name resolution must be completed by a dedicated domain name resolution server. The entire process is automated.
The domain name resolution protocol (DNS) is used to map host domain names and email addresses that are easy to recognize by computers. DNS is a c/s structure. The client is used by the user to find the address corresponding to a name, while the server is usually used to provide query services for others.
Step 1: the client sends a DNS request to the server. Step 2: the server sends an IP response to the client.
2. Briefly describe how to establish a TCP connection with the server.