[size=medium] 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