ddns_update.rb

#!/usr/bin/ruby
require 'net/http'
require 'pit'

config = Pit.get("dyn.value-domain.com", :require => {
  "domain" => "your domain in valuedomain",
  "password" => "your password in valuedomain"
})

Net::HTTP.version_1_2
Net::HTTP.start('dyn.value-domain.com', 80) {|http|
  response = http.get("/cgi-bin/dyn.fcg?d=#{config["domain"]}&p=#{config["password"]}&h=*")
  puts response.body
}