Last Updated on
The netstat command shows the services listening to ports on a Linux server and the details of any connections currently made to them. The connection details to consider during basic network daemon troubleshooting are the addresses that the daemon is listening on (including the port number), the daemon’s process identifier (PID), and the program name.
1 | netstat -tulnp |
Will yield an output similar to:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | 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 3159/mysqld tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN 1/systemd tcp 0 0 0.0.0.0:10000 0.0.0.0:* LISTEN 3253/perl tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 3209/sshd tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 3116/master tcp6 0 0 :::111 :::* LISTEN 1/systemd tcp6 0 0 :::80 :::* LISTEN 2801/httpd tcp6 0 0 :::22 :::* LISTEN 3209/sshd tcp6 0 0 ::1:25 :::* LISTEN 3116/master udp 0 0 0.0.0.0:960 0.0.0.0:* 2483/rpcbind udp 0 0 0.0.0.0:111 0.0.0.0:* 1/systemd udp 0 0 0.0.0.0:10000 0.0.0.0:* 3253/perl udp 0 0 127.0.0.1:323 0.0.0.0:* 2485/chronyd udp6 0 0 :::960 :::* 2483/rpcbind udp6 0 0 :::111 :::* 1/systemd udp6 0 0 ::1:323 :::* 2485/chronyd |
The netstat command line parameters are delineated as follows:
1 2 3 4 5 | t – Show TCP u – Show UDP l – Show only listening processes (netstat can show both listening and all established connections, i.e. as a client too) n – Do not resolve network IP address names or port numbers p – Show the process name that is listening on the port |
Comments