DNS Records Explained
A record: the most basic type of record, also known as address record, provides an IPv4 address to a domain name or sub-domain name. That record points the domain name to an IP address.
AAAA record: maps the hostname to 128-bits IPv6 address. For a long time, 32-bits IPv4 addresses served the purpose of identifying a computer on the internet. But due to the shortage of IPv4, IPv6 was created. The four “A” s (AAAA) are mnemonic to represent that IPv6 is four times larger in size than IPv4.
CNAME record: also known as Canonical Name record, creates an alias of one domain name. The aliased domain or sub-domain gets all the original Domain’s DNS records and is commonly used to associate subdomains with existing main domain.
MX record: also known as Mail Exchange records, tells which mail exchange servers are responsible for routing the email to the correct destination or mail server. For detailed analysis, use MX Record Lookup.
NS record: also known as Name Server records, points to the name servers which have authority in managing and publishing DNS records of that domain. These are the DNS servers that are authoritative to handle any query related to that domain. Use NS Lookup Tool to dig deeper.
PTR record: also known as Pointer record, points the IPv4 or IPv6 address to its machine’s hostname. It provides a reverse DNS record, also known as rDNS record, by pointing an IP address to the server’s hostname.
SRV record: also known as Service record, indicates which specific services the domain operates along with port numbers. Some Internet protocols such as the Extensible Messaging and Presence Protocol (XMPP) and the Session Initiation Protocol (SIP) often require SRV records.
SOA record: also known as Start of Authority records, provides essential information about the domain like identifying master node of domain authoritative nameserver, an email of the domain administrator, the serial number of DNS zone, etc.
TXT record: allows the website’s administrator to insert any arbitrary text in the DNS record.
CAA record: also known as Certification Authority Authorization record, reflects the public policy regarding the issuance of digital certificates for the domain. If no CAA record is present for your domain, any Certification Authority can issue an SSL certificate for your domain. However, by using this record, you can restrict which CA is authorized to issue digital credentials for your domain.