因爲公司的雲主機使用ifconfig和ip add命令都只能看到內網IP地址，而腳本里面又需要獲取公網IP地址進行一些動作；
# ip ad 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 08:00:27:d9:18:4e brd ff:ff:ff:ff:ff:ff inet 192.168.1.191/24 brd 192.168.1.255 scope global eth2 inet6 fe80::a00:27ff:fed9:184e/64 scope link valid_lft forever preferred_lft forever
這裏看不到公網IP，知呢個看到內網IP地址，可以通過curl ip.cip.cc來獲取公網IP地址
# curl ip.cip.cc 183.xx.xx.xx