Reverse DNS lookup (also known as rDNS) is a process to determine the hostname associated with a given IP address.
Typically, the DNS is used to determine what IP address is associated with a given hostname; so to reverse resolve a known IP address is to lookup what the associated hostname for it. A reverse lookup is often referred to simply as reverse resolving, or more specifically reverse DNS lookups.
The most common uses of the reverse DNS are:
- Network troubleshooting
- Avoiding spammers and phishers
All this by using a forward confirmed reverse DNS.
Simply enter the IP address to be checked (Your current IP will be entered in to the box automatically), then press the ‘Lookup’ button.The rDNS record for IP 0.0.0.0 resolves to 0.0.0.0 (If your rDNS record is just your IP address or 0.0.0.0 then it's not properly configured!)