How do you check for a specific port being used on a system?

Using the netstat command is a widely accepted method for checking if a specific port is being used on a system. The netstat utility can display active connections, including listening ports and the state of network connections, which is essential for troubleshooting network issues or verifying that an application is correctly configured to listen on a specific port.

When you run netstat with the appropriate flags (for example, netstat -tuln), it will show you TCP and UDP ports that are currently listening for connections. Additionally, it provides the PID (process ID) associated with the port, allowing system administrators to identify which application is using that port.

The other options, including the port, checkport, and connection commands, are not standard commands found on most Linux distributions for checking port usage, making them less relevant in this context. Thus, understanding the capabilities of netstat is crucial for managing network services effectively in a Linux environment.