Reverse DNS (rDNS) is the process of resolving an IP address back to a hostname. This is the opposite of a standard DNS lookup (A record), which resolves a hostname to an IP address.
Why is it used?
- Email Verification: Mail servers use rDNS to verify that an incoming email comes from a legitimate server.
- Network Troubleshooting: Helps identify the source of network traffic or potential security threats.
- Logging & Analytics: Web servers often log the hostname of visitors instead of just the IP address for better readability.