How can you determine occupied ports on a server using Bash?

To identify occupied ports on a server in Bash, you can use several commands:

• netstat -tuln — shows all listening TCP and UDP ports.
• ss -tuln — a modern alternative to netstat, displays a list of listening ports.
• lsof -i — shows open network connections and ports.

Example usage:

sudo netstat -tuln | grep LISTEN

This command will output a list of all ports that are in the listening state (occupied by server applications).