Edit Question - KnowledgeHub

Title Body

I'm in an environment with a lot of computers that haven't been properly inventoried. Basically, no one knows which IP goes with which mac address and which hostname. So I wrote the following: # This script goes down the entire IP range and attempts to # retrieve the Hostname and mac address and outputs them # into a file. Yay! require "socket" TwoOctets = "10.26" def computer_exists?(computerip) system("ping -c 1 -W 1 #{computerip}") end def append_to_file(line) file = File.open("output.txt", "a") file.puts(line) file.close end def getInfo(current_ip) begin if computer_exists?(current_ip) arp_output = `arp -v #{current_ip}` mac_addr = arp_output.to_s.match(/..:..:..:..:..:../) host_name = Socket.gethostbyname(current_ip) append_to_file("#{host_name[0]} - #{current_ip} - #{mac_addr}\n") end rescue SocketError => mySocketError append_to_file("unknown - #{current_ip} - #{mac_addr}") end end (6..8).each do |i| case i when 6 for j in (1..190) current_ip = "#{TwoOctets}.#{i}.#{j}" getInfo(current_ip) end when 7 for j in (1..255) current_ip = "#{TwoOctets}.#{i}.#{j}" getInfo(current_ip) end when 8 for j in (1..52) current_ip = "#{TwoOctets}.#{i}.#{j}" getInfo(current_ip) end end end Everything works except it does not find a Reverse DNS. Sample output that I'm getting is this: 10.26.6.12 - 10.26.6.12 - 00:11:11:9B:13:9F 10.26.6.17 - 10.26.6.17 - 08:00:69:9A:97:C3 10.26.6.18 - 10.26.6.18 - 08:00:69:93:2C:E2 If I do nslookup 10.26.6.12 then I get the correct reverse DNS so that shows that my machine is seeing the DNS server. I have tried Socket.gethostbyname , gethostbyaddr , but it doesn't work. Any guidance will be much appreciated.

Tags (comma-separated) Cancel