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@on195594
Created July 31, 2016 01:25
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如何查找Google的IP地址段
一般查找域名对应的IP,可以用这个命令 nslookup <域名>,但这样找,返回的ip比较少,今天看到一条命令,可以批量查找Google当前的IP范围。
命令及返回的结果如下:
# nslookup -q=TXT _netblocks.google.com 8.8.8.8
Server: 8.8.8.8
Address: 8.8.8.8#53
Non-authoritative answer:
_netblocks.google.com text = "v=spf1 ip4:64.18.0.0/20 ip4:64.233.160.0/19 ip4:66.102.0.0/20 ip4:66.249.80.0/20 ip4:72.14.192.0/18 ip4:74.125.0.0/16 ip4:108.177.8.0/21 ip4:173.194.0.0/16 ip4:207.126.144.0/20 ip4:209.85.128.0/17 ip4:216.58.192.0/19 ip4:216.239.32.0/19 ~all"
Authoritative answers can be found from:
这条命令是从谷歌的DNS服务器(8.8.8.8),获取很多的IP地址段。每个地址段格式如下:
216.239.32.0/19
这是一个CIDR(无类别域间路由,Classless Inter-Domain Routing),前面的216.239.32.0是起始地址,后面的/19表示掩码的位数,这里具体的掩码是255.255.224.0,在这个掩码范围内的都是Google的IP,总计8190个。掩码位数越小,表示IP地址段的范围越大。上面查到的这些地址段表示的IP,全部加起来大概有二十多万个。
要根据CIDR计算地址范围可以点这里。
另外,VPS上安装的精简版Ubuntu,默认并没有安装nslookup,可以执行以下命令安装:
# apt-get install dnsutils
Centos安装nslookup的命令如下:
# yum install bind-utils
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