1. 可用使用工具nmap看ip 端口是否打开
nmap -Pn -p 80,443 45.76.204.75
Starting Nmap 7.70 ( https://nmap.org ) at 2019-10-27 23:04 EDT
Nmap scan report for 45.76.204.75.vultr.com (45.76.204.75)
Host is up (0.20s latency).
PORT STATE SERVICE
80/tcp closed http
443/tcp closed https
2.使用命令netstat -uplnt | less 看哪个服务在使用哪个端口。