RevealTheme logo

Consulta de DNS Reverso (PTR)

Encontre o nome de host associado a qualquer endereço IP por meio de registros PTR.

Como usar esta ferramenta

  1. 1

    Type or paste an IP address into the input box, for example 8.8.8.8 or an IPv6 address like 2001:4860:4860::8888.

  2. 2

    Click Lookup to send the address to our server, which runs a reverse DNS (PTR) query against the public DNS system.

  3. 3

    Read the returned hostnames in the results list, or the 'No PTR record found' notice if the address has no PTR record or the lookup fails.

  4. 4

    Try another address to compare results, for example a mail server IP versus a residential or cloud IP.

O que é a Consulta de DNS Reverso (PTR)?

O DNS direto mapeia nomes de host para IPs (example.com → 1.2.3.4). O DNS reverso faz o contrário: pergunta 'qual nome de host pertence a este IP?' por meio de registros PTR. Isso é crucial para a entregabilidade de e-mails: os servidores de e-mail sem registros PTR costumam ser rejeitados pelos grandes provedores (Gmail, Microsoft) como supostas fontes de spam.

Casos de uso comuns

  • Confirm a sending mail server's IP has a valid PTR record before going live, since Gmail and Microsoft 365 often reject or junk mail from IPs with no reverse DNS.

  • Read web server or firewall access logs and turn raw IP addresses into hostnames to spot which networks or providers are connecting.

  • Verify that a cloud or VPS provider correctly applied the custom PTR record you requested for an outbound IP.

  • Investigate a suspicious IP during incident response to see whether it points back to a known ISP, hosting company, or CDN.

  • Sanity-check a newly delegated IP block by confirming PTR records resolve as expected after a network migration.

  • Troubleshoot SSH or service connections where the daemon does a reverse lookup on the client IP and a missing PTR causes slow or failed logins.

Perguntas frequentes

Por que o Gmail exige registros PTR?
Os registros PTR demonstram que o proprietário do IP controla a zona de DNS reverso, um sinal de que o remetente é um operador legítimo e não uma rede de bots.

Ferramentas relacionadas