显示网络链接
netstat
-t:tcp协议相关
-a:所有状态
-n:以数字显示IP和端口
-u:udp相关协议
-l:处于监听状态
-p:显示相关进程以及PID
-tan
-uan
-tnl
-tnlp
命令# netstat -tan
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:2222 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
# netstat -uan
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
udp 0 0 172.17.42.1:123 0.0.0.0:*
udp 0 0 172.16.173.245:123 0.0.0.0:*
udp 0 0 127.0.0.1:123 0.0.0.0:*
# netstat -tnl
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:2222 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
# netstat -tnlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 3868/mysqld
tcp 0 0 0.0.0.0:2222 0.0.0.0:* LISTEN 1632/sshd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 2010/master