Reverse DNS

I want to do reverse dns. But Im having troubles,
I have

Domain: rbu.org
Hostname: fedora
ip: 192.168.7.80

Direct dns its workin for this host.
I know that i must create a in-addr.arpa zone. not, but im not sure how.
can anyone tell me how i make the to make to resolve de reverse convertion?
A link with info its gone be very apreciate.
thanks

 

You will need to ask your provider to set the reverse DNS to make it work outside your LAN.

 

I am the isp

I am the isp.
Its my DNS, my domain, my host.
I dont know how create a reverse resolution convertion rule

 

Is it also you who is supplying the internet connection to your server?

 

DNS reverse

DNS reverse

Yes I am.

 

Dns reverse intructions

I just need intructions to generate a reverse dns resolution to the example above.
Intructions to create the in-addr.arpa zone and the PTR, how to fill the fields.
Thanks again