While regular DNS translates domain names to IPs, reverse DNS does the opposite—translating IPs back to domain names. It's essential for email servers and security validation.
¿Qué es Reverse DNS?
Reverse DNS (rDNS) allows you to look up the hostname associated with an IP address. It uses special PTR (pointer) records stored in the in-addr.arpa domain.
For example, 192.0.2.1 is looked up as 1.2.0.192.in-addr.arpa.
Por qué importa el Reverse DNS
Reverse DNS serves several important purposes.
Email Deliverability
Mail servers reject messages from IPs without valid rDNS
Security Verification
Helps identify the source of network traffic
Logging & Analytics
Shows hostnames instead of IP addresses in logs
Spam Prevention
Forward-confirmed rDNS (FCrDNS) validates senders
Forward-Confirmed Reverse DNS
FCrDNS (Forward-Confirmed Reverse DNS) is when the reverse lookup matches the forward lookup. This is the gold standard for email authentication.
Example: 192.0.2.1 → mail.example.com (PTR) and mail.example.com → 192.0.2.1 (A record)
Setting Up Reverse DNS
Reverse DNS is configured by whoever controls the IP addresses—typically the IP owner or leasing provider.
Cuando arriendas IPs de IP Market, configuramos sus registros PTR según sus requisitos.