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What is DNS?

Like a letter in the post office, an address or coordinates is needed to locate a website on the internet world. A domain name system, also known as DNS, is the internet's answer to the Post Master. This article will explain the various parts of DNS and how each record type has a purpose.

Name Servers

Name Servers, also referred to as NS records, are the primary records in DNS that make an IP address answer back to a domain name on a server. If it weren't for name servers, people would need to use IP addresses to pull up websites rather than a domain name, making web addresses a lot harder to remember.

For example, the IP address:

http://50.116.120.13

Resolves to the domain:

https://support.hostgator.com

A Records

Address records, also known as A records, are the other side to name servers. Address records point a domain to an IP address on a server, making it resolve to a specified IP address.

CNAME

Canonical Name records, better known as CNAME records, serve as aliases for domain names of another canonical domain name. This normally works best for pointing domains with a subfolder to a subdomain under the same primary domain name.

A prime example of how this works is by using the URL:

http://hostgator.com/support

When the site resolves, you will see that it is the same as the domain:

https://support.hostgator.com

MX Records

Mail Exchange records, also known as MX records, are the primary records that direct email for a domain name. These records work in conjunction with the A records and NS records to direct the email received for a domain name to the proper mail server. Usually, MX records are prioritized with a number of preferences that will indicate which mail servers should be used when there are several listed.

PTR Records

Reverse DNS records, also known as a pointer or PTR records, are used to resolve IPs to a domain name and vice versa. That means you can make hostgator.com point to 10.0.0.1 and make a PTR record so that 10.0.0.1, if checked, would tell you that it belongs to hostgator.com. It also allows the receiver of your emails to check for possible spoof emails, which will be treated as spam. Without this record, the receiver must rely on guessing if your email might be spam.

TXT  Records

Text records, better known as TXT records, are custom records that contain human-readable data. TXT records are dynamic and can be used for several purposes, such as verifying domain ownership for services such as Google Workspace.

SRV Record

Service records, also known as SRV records, are used to point one domain to another domain name using a specific destination port. SRV records allow specific services, such as VOIP or IM, to be directed to a separate location.

AAAA Record

An AAAA record points a domain or subdomain to an IPv6 address in the same way that an A record does; however, A records use IPv4 addresses only. Currently, HostGator does not support IPV6 addresses.

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