Reverse DNS

Definitions

1. A DNS lookup that maps an IP address back to a hostname using PTR records instead of resolving a hostname to an IP. Reverse DNS is useful in logging, reputation checks, mail handling, and investigation, but the returned name is only as trustworthy as the party controlling that DNS zone.

   In plain English: A DNS lookup that asks which hostname is associated with an IP address.

   Example: "The mail server rejected the connection because the sending host had no meaningful reverse DNS and failed other reputation checks too."

Related Terms

• DNS resolver
• TTL
• DNS Record Types
• DNS Propagation
• CoreDNS
• NAT Security
• Packet Filter
• Port Forwarding
• Public Network