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#PTR

All articles DNS IP addresses Privacy Routing Troubleshooting

DNS·Oct 22, 2026·2 min read

How does reverse DNS work?

Reverse DNS turns an IP address into a name. How the PTR record works, who controls it and why mail servers care.

Tags

#IPv4
#IPv6
#NAT
#Basics
#CGNAT
#DNS
#IP address
#ISP
#Troubleshooting
#ASN
#Accuracy
#BGP
#CIDR
#DNSSEC
#Dual stack
#Dynamic IP
#Email
#Geolocation

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