nc扫描机器端口

# nc -z localhost 1-10000   //扫描本机1到1000端口，获取打开的端口
Connection to localhost 22 port [tcp/ssh] succeeded!
Connection to localhost 80 port [tcp/http] succeeded!
Connection to localhost 111 port [tcp/sunrpc] succeeded!
Connection to localhost 199 port [tcp/smux] succeeded!
Connection to localhost 3306 port [tcp/mysql] succeeded!
Connection to localhost 6010 port [tcp/x11-ssh-offset] succeeded!
Connection to localhost 6011 port [tcp/*] succeeded!
# 

-z      Specifies that nc should just scan for listening daemons, without sending any data to them.  It is  an error to use this option in conjunction with the -l option.