Understanding how to check listening ports on Linux is a fundamental skill for system administrators and network engineers. These ports are the endpoints for incoming network connections, and monitoring them is critical for ensuring the security and availability of your Linux system. Checking listening ports allows you to identify which services are running on your system, which ports they are using, and who is connected to them. This information can be used to troubleshoot network issues, identify security vulnerabilities, and optimize system performance.
There are several ways to check listening ports on Linux. One common method is to use the netstat command. Netstat displays a list of all active network connections, including the local and remote IP addresses, port numbers, and state of each connection. Another useful tool is the ss command, which provides more detailed information about listening ports, including the process that owns each port and the type of socket being used.