nmap查看服务器端口使用情况

nmap ip要扫描的服务器地址

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PORT      STATE  SERVICE
21/tcp    closed ftp
22/tcp    open   ssh
80/tcp    open   http
443/tcp   closed https
5901/tcp  closed vnc-1
20000/tcp open   dnp
20005/tcp closed btx
20031/tcp closed unknown
20221/tcp closed unknown
20222/tcp closed ipulse-ics
20828/tcp closed unknown
21571/tcp closed unknown
22939/tcp closed unknown
23502/tcp closed unknown
24444/tcp closed unknown
24800/tcp closed unknown
25734/tcp closed unknown
25735/tcp closed unknown
26214/tcp closed unknown
27000/tcp closed flexlm0
27352/tcp closed unknown
27353/tcp closed unknown
27355/tcp closed unknown
27356/tcp closed unknown
27715/tcp closed unknown
28201/tcp closed unknown
30000/tcp closed unknown