What is DNS?
The DNS stands for Domain Name System is a database system that translates an IP address into a domain name. In other words you can say its is a system of servers located throughout the Internet that handle Internet connections and the routing of email. Also known as Domain Name Server.
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This List of DNS record types (Record Type, Meaning, Value & Description ) provides an overview of types of database/resource records stored in the zone files of the DNS.
A Record : Address Record (1)
Returns a 32-bit IPv4 address, commonly used to map hostnames to an IP address of the host.
AAAA Record : IPv6 Address Record (28)
Returns a 128-bit IPv6 address, commonly used to map hostnames to an IP address.
AFSDB Record : AFS Database Record (18)
Location of database servers of an AFS cell. This record is commonly used by AFS clients to contact AFS cells outside their local domain.
CERT Record : Certificate Record (37)
Stores information like PKIX, SPKI, PGP, etc.
CNAME Record : Canonical Name Record (5)
Alias of one name to another: the DNS lookup will continue by retrying the lookup with the new name.
DHCID Record : DHCP Identifier (49)
Used in conjunction with the FQDN option to DHCP.
DNAME Record : delegation Name (39)
DNAME will delegate an entire portion of the DNS tree under a new name.
DNSKEY Record : DNS Key Record (48)
The key record used in DNSSEC. Uses the same format as the KEY record.
DS Record : Delegation Signer (43)
The record used to identify the DNSSEC signing key of a delegated zone.
HIP Record : Host Identity Protocol (55)
Method of separating the end-point identifier and locator roles of IP addresses.
IPSECKEY Record : IPSEC Key (45)
Key record that can be used with IPSEC.
KEY Record : Key Record (25)
Used only for TKEY.
LOC Record : Location Record (29)
Specifies a geographical location associated with a domain name.
MX Record : mail exchange Record (15)
Maps a domain name to a list of mail exchange servers for that domain.
NAPTR Record : name server Record (2)
Delegates a DNS zone to use the given authoritative name servers.
NSEC Record : Next-Secure Record (47)
Part of DNSSEC—used to prove a name does not exist. Uses the same format as the (obsolete) NXT record.
NSEC3 Record : NSEC Record Version 3 (51)
Parameter record for use with NSEC3.
PTR Record : pointer Record (12)
Pointer to a canonical name. Unlike a CNAME, DNS processing does NOT proceed, just the name is returned. The most common use is for implementing reverse DNS lookups, but other uses include such things as DNS-SD.
RRSIG Record : DNSSEC Signature (46)
Signature for a DNSSEC-secured record set. Uses the same format as the SIG record.
SIG Record : Signature (24)
Signature record is used in SIG.
SOA Record : Start of Authority Record (6)
Specifies authoritative information about a DNS zone, including the primary name server, the email of the domain administrator, the domain serial number, and several timers relating to refreshing the zone.
SPF Record : SPF Record (99)
Specified as part of the SPF protocol, as an alternative to storing SPF data in TXT records. Uses the same format as the TXT record.
SRV Record : Service Locator (33)
Generalized service location record, used for newer protocols instead of creating protocol-specific records such as MX.
SSHFP Record : SSH Public Key Fingerprint (44)
Resource record for publishing SSH public host key fingerprints in the DNS System, in order to aid in verifying the authenticity of the host.
TXT Record : Text Record (16)
Originally for arbitrary human-readable text in a DNS record. Since the early 1990s, however, this record more often carries machine-readable data, opportunistic encryption, Sender Policy Framework (deprecated), DomainKeys, DNS-SD, etc.
The list of other less common DNS records is given below.
A6 Record : A6 (Experimental) (38)
All Record : A Request for All Records (255)
APL Record : APL (42)
ATMA Record : ATM Address (34)
AXFR Record : Transfer of an Entire Zone (252)
DLV Record : DNSSEC Lookaside Validation (32769)
EID Record : Endpoint Identifier (31)
GID Record : IANA-Reserved (102)
GPOS Record : Geographical Position (27)
HINFO Record : Host Information (13)
ISDN Record : ISDN address (20)
IXFR Record : Incremental Transfer (251)
KX Record : Key Exchanger (36)
MAILA Record : Mail Agent RRs (Obsolete - see MX) (254)
MAILB Record : Mailbox-Related RRs (MB, MG or MR) (253)
MB Record : Mailbox Domain Name (EXPERIMENTAL) (7)
MD Record : Mail Destination (Obsolete - use MX) (3)
MF Record : Mail Forwarder (Obsolete - use MX) (4)
MG Record : Mail Group Member (EXPERIMENTAL) (8)
MINFO Record : Mailbox or Mail List Information (14)
MR Record : Mail Rename Domain Name (EXPERIMENTAL) (9)
NAPTR Record : Naming Authority Pointer (35)
NIMLOC Record : Nimrod Locator (32)
NINFO Record : NINFO (56)
NSAP Record : NSAP Address, NSAP Style A record (22)
NSAP-PTR Record : Domain Name Pointer, NSAP Style (23)
NSEC3 Record : NSEC3 (50)
NULL Record : A NULL RR (EXPERIMENTAL) (10)
NXT Record : Next Domain - OBSOLETE (30)
OPT Record : OPT (41)
Private Record : For Private Use Only (65280-65534)
PX Record : X.400 Mail Mapping Information (26)
Reserved Record : Reserved (65535)
RKEY Record : RKEY (57)
RP Record : Responsible Person (17)
RT Record : Route Through (21)
SINK Record : SINK (40)
TA Record : DNSSEC Trust Authorities (32768)
TKEY Record : Transaction Key (249)
TSIG Record : Transaction Signature (250)
UID Record : IANA-Reserved (101)
UINFO Record : IANA-Reserved (100)
Unassigned Record : Unassigned Range (104-248)
Unassigned Record : Unassigned Range (256-32767)
Unassigned Record : Unassigned Range (32770-65279)
Unassigned Record : Unassigned Range (52-54)
Unassigned Record : Unassigned Range (58-98)
UNSPEC Record : IANA-Reserved (103)
WKS Record : A Well Known Service Description (11)
X25 Record : for X.25 PSDN Address (19)