查询服务器外网IP和根据域名查询外网IP

    linux经常需要查询服务器的外网IP，或是通过域名来查询该服务器对应的外网IP


1、查询本地服务器外网IP

curl ipinfo.io/ip


2、通过域名查询外网IP

通过执行命令：nslookup www.baidu.com 可得到下面结果

Non-authoritative answer:
www.baidu.com   canonical name = www.a.shifen.com.
Name:   www.a.shifen.com
Address: 14.215.177.37
Name:   www.a.shifen.com
Address: 14.215.177.38



或执行：ping www.baidu.com 则得到下面一个IP


PING www.a.shifen.com (14.215.177.37) 56(84) bytes of data.
64 bytes from 14.215.177.37: icmp_seq=1 ttl=47 time=7.53 ms
64 bytes from 14.215.177.37: icmp_seq=2 ttl=47 time=7.52 ms
64 bytes from 14.215.177.37: icmp_seq=3 ttl=47 time=7.58 ms
64 bytes from 14.215.177.37: icmp_seq=4 ttl=47 time=7.58 ms