Netstat, short for network statistics, is a built-in command-line tool used in Linux systems for network troubleshooting and performance measurement. It provides statistics for protocols, a list of open ports, routing table information, and other important network details. Administrators and developers work with netstat to examine network issues and understand how a system communicates with others.
Its functionality is extended owing to various command-line options it supports, which could be used singularly or combinedly to fine-tune the output. These might include displaying numerical addresses instead of names (-n), continuous monitoring (-c), or spotting connections on a specific protocol (-t, -u).
Here is a brief snippet of how netstat may typically be used:
# List all connections with numerical values.
netstat -n