How does DNS work?
The domain name system (DNS) is the resolution of a domain name to an IP address through a DNS Server. DNS can be thought of as a domain lookup, website IP checker, or IP finder, as it searches domains or websites to produce any related IP addresses. Essentially, it converts domain names to IP addresses for the user.
Typical DNS queries are sent through four different server types: the DNS resolver (also known as the recursor), the root nameserver, the TLD nameserver, and the authoritative nameserver. The domain name system recursor gets the query and communicates with other domain name system servers in order to get the correct IP address.
Once it’s located, the domain name system recursor will send the query to the three other domain name system servers. Next, the root server, designated as the Internet’s domain name system root zone, responds to requests sent in the root zone. A list of authoritative nameservers that correspond with TLDs gets sent back as a response.
The TLD nameserver will then store the second-level domain IP address and release the website’s IP address. The query gets sent to the domain’s nameserver. Finally, the authoritative nameserver can respond to the original domain name system query.
What is DNS lookup used for?
DNS record lookups are used for translating IP addresses and domain names. With the DNS lookup tool, users can find the IP address of a domain name and other information related to domains.
Users can also perform a reverse DNS lookup. This uses pointer records to query an IP address in order to find a hostname. It essentially finds the "name" of IP addresses. Note that some IP addresses will not return a domain name if there are multiple domains associated with a given IP address. Do a reverse IP lookup to check DNS and find your IP's domain. If you want to find your own IP, the WhatIsMyIP homepage shows you your IP along with all the related IP details.
Overview of the forward DNS lookup process
The forward lookup, or simple DNS lookup, is the most commonly used approach to DNS. The forward approach to DNS is simply finding out the IP address of a domain.
People tend to find it difficult to remember long strings of numbers. Instead, it's easier to remember a domain name that uses words, like 'google.com' rather than '126.96.36.199.'
However, electronic devices use streams of 1s and 0s to communicate. The only way for one computer to communicate with another is by unique identification. The method of identification used on the Internet is IP addresses.
Here are the simple steps for DNS resolution:
- A user enters a domain name into their Internet browser, like www.whatismyip.com.
- The computer sends the domain name as a DNS request to the user's Internet Service Provider (ISP).
- The ISP determines if it has the IP address associated with that name.
- If it does not, the ISP forwards the request to other providers in an effort to lookup DNS records that contains the data.
- Once the record is found, the IP address of the domain is returned to the user.
- Now, the user's computer can communicate directly with the server.
How to perform a DNS lookup
To use the DNS lookup command, enter the domain URL into the DNS lookup tool above and select Lookup or press Enter. The DNS tracker will return the IPv4 address records for a domain in a domain lookup.
You can also use the nslookup command to check nameservers for domains rather than using the full DNS lookup command. Furthermore, you can use the DNS checker above to perform a DNS lookup in-site.
To do a DNS lookup in a Windows computer, go to Start, then Run, and type command to open the command prompt. Type nslookup and hit Enter. Your search will bring back information about your local DNS default server and IP address.
If you're using a Mac computer, go to the Finder menu in the upper right corner and click Go. Find Utilities, then select Terminal. In the box that pops up, type nslookup followed by the IP address or domain you want to query, and then hit Enter. Your search will return the DNS server and IP address of the information you entered.
If you want to know how to look up a domain to find the owner, use a WHOIS Domain Lookup or the WHOIS IP Lookup tool once you have a domain's IP address. The WHOIS lookup works to check domain owners and identifies the owners of various IP addresses.