Netstat-an looks at the network port lsof-i:port. Through lsof-i:port, you can see the programs running at the specified port and the current connection.

Nmap port scanning

How to find out the list of all open ports in Linux?

Use the command netstat-antu to view the openness of all tcp and udp ports, where -a means to view all ports, and by default, only viewing the connected n means to display numerical port numbers without displaying names. For example, displaying 80 instead of /ipv4/ip_local_port_range defines the port range of local TCP/UDP. You can define net. Ipv4.ip _ local _ port _ range =102465000 in /etc/sysctl.conf, and the available port range becomes 1024~65000.

How to check which program of linux occupies the port?

Check the port usage and use the netstat command.

View the connected service port (ESTABLISHEDnetstat-a) View all service ports (LISTEN, ESTABLISHED)netstat-ap View port 8080, and then you can combine the grep command: netstat-ap|grep8080 If you view port 8888, then enter: lsof-i:8888 at the terminal.