Talk about dns resolution process.

Enter the domain name in the browser, and the operating system will first check whether the local hosts file has this URL mapping relationship. If so, it will first call this IP address mapping to complete domain name resolution. If there is no mapping for this domain name in the host, please search the local DNS resolver cache to see if there is a mapping relationship for this URL. If yes, directly return to complete domain name resolution. If there is no corresponding URL mapping relationship between the host and the local DNS resolver cache, we will first find the preferred DNS server set in the TCP/ip parameters, which we call the local DNS server here. When the server receives the query, if the domain name to be queried is included in the local configuration area resources, it will return the resolution result to the client to complete the domain name resolution, which is authoritative. If the domain name to be queried is not resolved by the local DNS server area, but the server has cached this URL mapping relationship, it is not authoritative to call this ip address mapping to complete domain name resolution. All the complete contents go to the operation and maintenance section of the dark horse programmer community, and there are answers to related technical questions.