Ruby 中的反向 DNS?

问题描述

我所在的环境中有很多未使用过的计算机妥善盘点.基本上，没有人知道哪个 IP 配哪个mac 地址和哪个主机名.所以我写了以下内容:

I'm in an environment with a lot of computers that haven't beenproperly inventoried. Basically, no one knows which IP goes with whichmac 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}
")
   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

除了找不到反向 DNS 之外，一切正常.

Everything works except it does not find a Reverse DNS.

我得到的示例输出是这样的:

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

如果我执行 nslookup 10.26.6.12 然后我得到正确的反向 DNS 所以这表明我的机器正在查看 DNS 服务器.

If I do nslookup 10.26.6.12 then I get the correct reverse DNS sothat shows that my machine is seeing the DNS server.

我试过Socket.gethostbyname、gethostbyaddr，但没有用.

任何指导将不胜感激.

推荐答案

今天我也需要反向 DNS 查找，我找到了非常简单的标准解决方案:

Today I also needed reverse DNS lookup and I've found very simple standard solution:

require 'resolv'
host_name = Resolv.getname(ip_address_here)

它似乎使用了超时，这有助于在粗糙的情况下.

It seems it uses timeout which helps in rough cases.

这篇关于Ruby 中的反向 DNS?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！