網絡排查監聽端口

方法一：netstat

zljump@test-pressure-zlstream-01 ~]$ netstat -anp | grep "sdu"

(No info could be read for "-p": geteuid()=1002 but you should be root.)

[xzljump@test-pressure-zlstream-01 ~]$ sudo netstat -anp | grep "sdu"

tcp        0      0 0.0.0.0:567             0.0.0.0:*               LISTEN      24878/./sdumservice

tcp        0      0 0.0.0.0:8088            0.0.0.0:*               LISTEN      24878/./sdumservice

[xzljump@test-pressure-zlstream-01 ~]$ sudo netstat -anp | grep "sdu"

tcp        0      0 0.0.0.0:567             0.0.0.0:*               LISTEN      24878/./sdumservice

tcp        0      0 0.0.0.0:8088            0.0.0.0:*               LISTEN      24878/./sdumservice

[xzljump@test-pressure-zlstream-01 ~]$ sudo netstat -anp | grep "sdu"

tcp        0      0 0.0.0.0:567             0.0.0.0:*               LISTEN      24878/./sdumservice

tcp        0      0 0.0.0.0:8088            0.0.0.0:*               LISTEN      24878/./sdumservice

[xzljump@test-pressure-zlstream-01 ~]$ sudo netstat -anp | grep "sdu"

tcp        0      0 0.0.0.0:567             0.0.0.0:*               LISTEN      24878/./sdumservice

tcp        0      0 0.0.0.0:8088            0.0.0.0:*               LISTEN      24878/./sdumservice

方法二：抓包

[xzljump@test-pressure-zlstream-01 ~]$ tcpdump -i any -s 20480 -A port 8088

[xzljump@test-pressure-zlstream-01 ~]$ sudo tcpdump -i any -s 20480 -A port 8088

抓包網絡分析：

抓包判斷是否建立TCP連接

TCP建立連接

https://www.cnblogs.com/GoForMyDream/p/8707813.html

方法四：設置一個啓動一個端口

nc -l 40000 起一個40000端口

在服務端查看有沒有監聽到

telnet 192.168.1.31 40000