June 2019
Intermediate to advanced
328 pages
7h 27m
English
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Finding Information About Domain Names
When you make a request to facebook.com, your computer looks up the domain name to translate that domain name into an IP address so your computer can make that connection. An IP address points to a computer on the Internet, but a domain name is easier to remember than a group of numbers. Domain Name System (DNS) servers store the mappings of IP addresses, along with other information. There are several command-line tools you can use to query these servers.
Use the dig command to “dig” through domain name records and find the IP addresses associated with those. It’s a reliable way to get information about a domain:
| | $ dig facebook.com |
| | ; <<>> DiG 9.11.3-1ubuntu1.2-Ubuntu <<>> facebook.com |
| | ;; global ... |