Centos Linux使用nc进行网络探测和监听

探测TCP端口

[root@sre01 ~]# nc -zv 192.168.236.100 22
Ncat: Version 7.50 ( https://nmap.org/ncat )
Ncat: Connected to 192.168.236.100:22.
Ncat: 0 bytes sent, 0 bytes received in 0.02 seconds.


[root@sre01 ~]# nc -zv 192.168.236.100 23
Ncat: Version 7.50 ( https://nmap.org/ncat )
Ncat: Connection refused.


探测UDP端口
[root@sre01 ~]# nc -zv -u 192.168.236.100 111
Ncat: Version 7.50 ( https://nmap.org/ncat )
Ncat: Connected to 192.168.236.100:111.
Ncat: Connection refused.


在指定端口监听（tcp 234端口）
[root@sre01 ~]# nc -l 234