Resolve domain from IP address using Ruby

Question

I have requirements to find domain name using IP address using Ruby.

I have some IP addresses. I got every time different random IP address. But I have to filter the IP addresses that have a domain name.

How to find the domain name?

Answer 1

You can use the stdlib Resolve.

Resolv is a thread-aware DNS resolver library written in Ruby. Resolv can handle multiple DNS requests concurrently without blocking the entire Ruby interpreter.

Resolv can look up various DNS resources using the DNS module directly.

require 'resolv'
Resolv.getname "210.251.121.214" # => "ci.ruby-lang.org"