RDNS (Reverse DNS) resolves an IP address to a domain name. To find rDNS for an IP address, you can use the command nslookup.
nslookup IP_ADDR_HERE
In the above screenshot, IP address 51.38.246.115 have reverse DNS set to ok.serverok.in
You also need to verify the hostname points to IP address. Many server providers check this before settings reverse dns entry.
root@server12:~# nslookup ok.serverok.in Server: 213.133.99.99 Address: 213.133.99.99#53 Non-authoritative answer: Name: ok.serverok.in Address: 51.38.246.115 root@server12:~#
Find rDNS using dig command
To find rDNS of an IP address, use the command
dig +short -x IP_ADDR_HERE
Example
root@server12:~# dig +short -x 51.38.246.115 ok.serverok.in. root@server12:~# root@server12:~# dig +noall +answer -x 51.38.246.115 115.246.38.51.in-addr.arpa. 86400 IN PTR ok.serverok.in. root@server12:~#
Find rDNS using host command
host IP_ADDR_HERE
Example
root@server12:~# host 51.38.246.115 115.246.38.51.in-addr.arpa domain name pointer ok.serverok.in. root@server12:~#
Back to Reverse DNS