DNS

What are DNS records?

Much like a directory, DNS records are instructions created by and
stored on DNS servers in what’s known as a zone file. These records
provide important and relevant details about domains and
hostnames. Just like a building directory, these listings help
DNS servers send queries to the right place.

Much like a directory, DNS records are instructions created by and stored on DNS servers in what’s known as a zone file. These records provide important and relevant details about domains and hostnames. Just like a building directory, these listings help DNS servers send queries to the right place.

DNS record types

A record (Address)

An A record is most commonly used to map a fully qualified domain name (FQDN) to an IPv4 address and as a translator to convert domain names to IP addresses.

AAAA record (Quad A)

Similar to an A record, an AAAA record maps a FQDN to an IPv6 address (IPv6 addresses are preferred by smartphones, when available).

CNAME record (Canonical Name)

A CNAME record is used in place of an A record when a domain or subdomain is an alias of another domain. CNAME records always point to a domain instead of an IP address.

When a domain or subdomain is an alias of another domain, this record is used in place of an A record. CNAME records always point to a domain instead of an IP address. This record is ideal for IP addresses that will change over time as it allows for changes without affecting user bookmarks.

ANAME record

ANAME records allow you to point the root of your domain to a hostname or FQDN.

SOA record (Start of Authority)

SOA records store information about domains. They direct DNS zone propagation to secondary nameservers.

NS record (Name Server)

NS records specify which nameservers are authoritative for a domain or subdomains. Note: NS records should not be pointed to a CNAME.

MX record (Mail eXchange)

MX records use mail servers to map where to deliver email for a domain. Note: MX records should only point to a mail server name, not to an IP address.

TXT record (Text)

TXT records allow administrators to add limited human- and machine-readable notes and can be used for email validation, site and ownership verification, framework policies, etc. These records do not require specific formatting. 

SRV record (Service)

SRV records allow services such as instant messaging or VoIP to be directed to a separate host and port location. 

PTR record (Pointer) 

PTR records are used in reverse DNS lookups. While A and AAAA records map FQDNs to IP addresses, PTR records do the opposite, mapping IP addresses to domain names. These records require domain authority and can’t exist in the same zone as other DNS record types. Reverse zones are the ideal location for PTR records.

SPF record (Sender Policy Framework)

SPF records help limit spammers and prevent email spoofing. Note: This record type has been deprecated in favor of TXT record types and may no longer be supported by all providers.