What is the difference between the DNS resolution process and iterative and recursive queries?

Http://zhangbin.blog.51cto.com/666869/286257

 

1. recursive query:
Generally, recursive queries are performed between the client and the server. After a request is sent from the client to the DNS server, if the DNS server itself cannot be resolved, a query request is sent to another DNS server, the result is forwarded to the client;
2. Iterative query (repeated query ):
Generally, an iterative query is performed between DNS servers. For example, if dns2 cannot respond to a dns1 request, it will send the IP address of dns3 to dns2 so that it can send a request to dns3;

For example, if a student asks a teacher a question, Mr Wang tells him that the answer is recursive query. During this period, Mr. Wang may not. At this time, Mr. Wang asked Mr. Zhang. The query between them is called iterative query!