1. The root servers, top-level domain with the server, and what is the relationship and difference between authoritative DNS?
2. For example, when I visit http://csdn.net, how DNS works? How work process with the root servers, top-level domain with the server, and authoritative DNS into contact??
First 32 x,
CodePudding user response:
DNS service in general is the use of the Internet on the primary level of DNS server,If you want to visit the CSDN, CSDN himself first to business registered csdn.net DNS domain name management (after the registration, csdn.net will be in the management of the domain name resolution server database tables to save a DNS and IP mapping table), this example, the domain name manager is.net domain name service (while we are often called the DNS server. NET server)
Now, you need to visit the site at home (for example, your computer is connected to Shanghai telecom network) :
Step 1: the browser will see if there are any local Cache good corresponding relationship between domain name and IP, if the local have, use, directly (of course have a valid Cache)
Step 2: if the browser: no, your machine will ask Shanghai telecom domain name server area for parsing, if Shanghai telecom DNS server has returned directly (note Shanghai DNS servers will be responsible for the entire domain name resolution of Shanghai telecom, all with his latest CSDN domain name and IP for the possibility of a major), your browser will first after the analytic results are cached in the local, and then made the request, the corresponding IP
Step 3: if the Shanghai DNS server has no corresponding data expiration (or data), it will ask China telecom the DNS server,
And so on until the.net root DNS server, there must be a (because CSDN already registered here),
Note that DNS server usually caching DNS at all levels of DNS and IP corresponding table in response to a large number of DNS request,
On Windows, you can use nslookup command to see what a DNS is parsed into IP: http://www.net.cn/service/faq/yuming/url/200603/736.html
CodePudding user response:
In addition, it is important to note that if there is a level 3 domain names, such as bbs.csdn.net, CSDN may use their own DNS servers to manage all the ending for the csdn.net domain name resolution, so that your DNS request will eventually go to CSDN own DNS domain name resolution server,CodePudding user response:
When I visit the CSDN, and the world's only 13 root server happen relationship? Or, when will happen relationship?
CodePudding user response: