linux下查看开放的端口

Nmap是一款针对大型网络的端口扫描工具,它也适用于单机扫描,它支持很多扫描，也同时支持性能和可靠性统计。

[root@localhost ~]# yum install namp[root@localhost ~]# nmap 127.0.0.1Starting Nmap 5.51 ( http://nmap.org ) at 2017-05-18 22:39 PDTNmap scan report for localhost (127.0.0.1)Host is up (0.0000020s latency).Not shown: 997 closed portsPORT    STATE SERVICE22/tcp  open  ssh25/tcp  open  smtp631/tcp open  ippNmap done: 1 IP address (1 host up) scanned in 0.07 seconds