Registros DNS

Pesquise e aprenda tipos de registro DNS — exemplos, quando usar, referências RFC

Referência para tipos de registro DNS. Cada entrada tem uma descrição, exemplo de sintaxe de arquivo de zona e observações sobre quando usá-lo.

Pesquisar

14 tipos de registro

Address (IPv4)RFC 1035

Maps a hostname to a 32-bit IPv4 address.

Exemplo

example.com.    300    IN  A    93.184.216.34

Quando usar

Standard hostname → IPv4 mapping. Most websites have at least one A record.

AAAA

Address (IPv6)RFC 3596

Maps a hostname to a 128-bit IPv6 address.

Exemplo

example.com.    300    IN  AAAA  2606:2800:220:1:248:1893:25c8:1946

Quando usar

IPv6 endpoint resolution. Modern dual-stack deployments include both A and AAAA.

CNAME

Canonical NameRFC 1035

Alias of one hostname to another. The DNS lookup follows the alias.

Exemplo

www.example.com.   300   IN  CNAME  example.com.

Quando usar

Pointing subdomains (www, app) to a primary host. Cannot coexist with other records on the same name.

Mail ExchangeRFC 1035

Specifies mail servers for a domain, with a priority value.

Exemplo

example.com.    300    IN  MX    10 mail.example.com.

Quando usar

Required for receiving email. Lower priority = higher preference.

TXT

TextoRFC 1035

Arbitrary text strings. Used for verification and policy declarations.

Exemplo

example.com.    300    IN  TXT   "v=spf1 include:_spf.google.com ~all"

Quando usar

SPF/DKIM/DMARC email auth, domain verification (Google/Facebook), public keys.

Name ServerRFC 1035

Delegates a DNS zone to authoritative name servers.

Exemplo

example.com.    300    IN  NS    ns1.example.com.

Quando usar

Required at the apex of every zone. Lists which servers answer queries for this domain.

SOA

Start of AuthorityRFC 1035

Authoritative info about the zone: primary NS, admin email, serial, timers.

Exemplo

example.com.   3600   IN  SOA   ns1.example.com. admin.example.com. 2026050701 7200 3600 1209600 3600

Quando usar

Exactly one per zone, at the apex. Required by DNS spec.

SRV

Service LocatorRFC 2782

Specifies the host/port for a service — protocol, weight, priority.

Exemplo

_sip._tcp.example.com. 300 IN SRV 10 60 5060 sipserver.example.com.

Quando usar

SIP/XMPP/LDAP/Minecraft service discovery. Format: _service._proto.name.

CAA

Certification Authority AuthorizationRFC 8659

Restricts which CAs can issue TLS certificates for the domain.

Exemplo

example.com.   300    IN  CAA   0 issue "letsencrypt.org"

Quando usar

Prevent unauthorized CAs from issuing certs for your domain. Recommended for security.

PTR

Pointer (Reverse DNS)RFC 1035

Maps an IP address back to a hostname (in in-addr.arpa or ip6.arpa).

Exemplo

34.216.184.93.in-addr.arpa.  300  IN  PTR  example.com.

Quando usar

Reverse DNS for email server reputation (spam filters), logging.

HTTPS

HTTPS Service BindingRFC 9460

Encrypted ALPN/SNI hints for HTTPS connections; supports ECH.

Exemplo

example.com.   300    IN  HTTPS  1 . alpn="h3,h2"

Quando usar

Modern HTTPS optimization (HTTP/3 hint, encrypted client hello). Browser support growing.

SVCB

Service BindingRFC 9460

Generic service binding (HTTPS is a specific subtype).

Exemplo

_dns.example.com. 300 IN SVCB 1 dns.example.com. alpn="dot"

Quando usar

Generic service alias with hints (e.g., DNS over TLS). Less common than HTTPS.

Delegation SignerRFC 4034

DNSSEC — fingerprint of child zone's KSK, stored in parent zone.

Exemplo

example.com. 86400 IN DS 12345 13 2 ABC123...

Quando usar

DNSSEC chain of trust. Required when a zone is DNSSEC-signed.

DNSKEY

DNS Public KeyRFC 4034

DNSSEC — public key for verifying signatures in the zone.

Exemplo

example.com. 86400 IN DNSKEY 257 3 13 ABC456...

Quando usar

DNSSEC verification. Stored at zone apex; signed by KSK referenced by parent's DS.

Como usar

Digite um tipo de registro, palavra-chave ou caso de uso no campo de pesquisa (ex: "MX", "mail", "DNSSEC").
Navegue pelos cartões correspondentes, cada um mostrando o distintivo do tipo de registro, nome completo, referência RFC, descrição, um exemplo concreto e quando usá-lo.
Deixe o campo vazio para ver todos os 14 tipos de registro ao mesmo tempo.

Exemplos

Procurar "MX" mostra o registro de Mail Exchanger, RFC 1035, com exemplo "example.com. IN MX 10 mail.example.com." e explica que é usado para rotear e-mail para um domínio.
Procurar "DNSSEC" retorna cartões DS e RRSIG explicando como respostas DNS são criptograficamente assinadas.

Verifique as saídas antes de usar em produção. Sem garantia — veja Termos.