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Networking Fundamentals · Foundational

Pointer Record (PTR)

A DNS record that maps an IP address to a host name, used for reverse lookups.

Definition

PTR records live in reverse zones under in-addr.arpa (IPv4) or ip6.arpa (IPv6). Mail servers often check reverse DNS to score spam.

Example

10.2.0.192.in-addr.arpa. PTR server.example.com.

Exam tip

PTR = reverse lookup; IP to name.

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