In this tutorial, we will discuss your mastering the netstat command on Linux. Netstat is one of the most versatile and powerful tools in a Linux administrator’s arsenal. This command line utility provides valuable insight into the network connections and communication happening on a Linux system. Whether you’re a seasoned system administrator or just starting out, understanding the
netstat command is an essential part of your Linux education. In this post, we’ll explore the many uses of
netstat, from displaying active network connections to monitoring the health of your network interfaces. By the end, you’ll have a complete understanding of this essential Linux tool and how it can help you troubleshoot network problems and optimize your system’s performance.
What is Netstat Command?
The Netstat command is used to display various information about the network status and active connections on a Linux system. It can be used to display information about both incoming and outgoing network connections, and it provides detailed information about the state of these connections, including the local and remote IP addresses, the port number, and the state of the connection.
Basic Syntax and Options of Netstat Command
The basic syntax of the
netstat a command is as follows:
The following are some of the most commonly used Netstat options:
|-a||Shows all active connections and the status of these connections.|
|-t||Shows only TCP connections.|
|-u||Shows only UDP connections.|
|-l||Shows only listening connections.|
|-p||Shows the process ID and name of the process associated with each connection.|
|-n||Displays addresses and port numbers in numerical format, rather than resolving them to hostnames or port names.|
Here are some examples of how you can use the
netstat command to gather information about your network:
- To display all active TCP connections, run the following command:
- To display all active UDP connections, run the following command:
- To display all active connections, including TCP and UDP connections, run the following command:
- To display all listening connections, run the following command:
- To display the process ID and name of the process associated with each connection, run the following command:
- To display addresses and port numbers in numerical format, run the following command:
- To view the active outgoing connections on a computer, you can use the following command:
netstat -n | grep ESTABLISHED
- To view the connections that are listening for incoming connections, you can use the following command:
netstat -an | grep LISTEN
- To display only the TCP connections on a computer, you can use the following command:
- To display only the UDP connections on a computer, you can use the following command:
- To display the network connections at regular intervals, you can use the following command:
netstat -atn | grep ESTABLISHED | watch -n 5
netstat a command is a powerful tool that can provide valuable information about your network. By using the various options and examples outlined in this article, you can quickly and easily monitor network connections, identify potential issues, and make informed decisions. Whether you are a network administrator or simply someone who wants to monitor their network, the
netstat a command is an essential tool to have in your toolkit.