Netstat vs. Netstat -a

Attribute	Netstat	Netstat -a
Displays active TCP connections	Yes	Yes
Displays active UDP connections	Yes	Yes
Displays listening ports	Yes	Yes
Displays the PID and process name for each connection	No	Yes
Displays the state of each connection	Yes	Yes

Introduction

Netstat and Netstat -a are two commonly used commands in networking to display network connections, routing tables, and interface statistics. While both commands provide valuable information about network activity, they have some key differences in terms of functionality and output. In this article, we will compare the attributes of Netstat and Netstat -a to help you understand when to use each command.

Netstat

Netstat is a command-line tool that displays active network connections, routing tables, and interface statistics. When you run the Netstat command without any options, it displays a list of active connections along with the protocol, local address, foreign address, and state of each connection. This information can be useful for troubleshooting network connectivity issues and monitoring network activity in real-time.

One of the key features of Netstat is its ability to display detailed information about individual network connections, including the process ID (PID) of the application that initiated the connection. This can be helpful for identifying which applications are using network resources and potentially causing network performance issues.

Netstat also allows you to filter the output based on specific criteria, such as protocol type, port number, or IP address. This can help you narrow down the list of network connections to focus on a specific subset of connections that meet your criteria.

Overall, Netstat is a powerful tool for monitoring network activity and troubleshooting network connectivity issues. However, it may not provide a comprehensive view of all network connections on the system, especially if there are a large number of connections.

Netstat -a

Netstat -a is a variation of the Netstat command that displays all active network connections, including listening and non-listening connections. When you run the Netstat -a command, it shows a list of all active connections along with the protocol, local address, foreign address, and state of each connection. This can be useful for getting a complete overview of all network connections on the system.

One of the main differences between Netstat and Netstat -a is that Netstat -a includes listening connections, which are connections that are waiting for incoming connections from other systems. By including listening connections in the output, Netstat -a provides a more comprehensive view of network activity on the system.

Netstat -a also displays information about non-listening connections, which are active connections that are not waiting for incoming connections. This can be helpful for identifying established connections and monitoring network traffic between systems.

Overall, Netstat -a is a useful tool for gaining a complete overview of all network connections on the system, including both listening and non-listening connections. It can be particularly helpful for monitoring network activity on servers and identifying potential security risks.

Comparison

• Netstat displays active network connections, routing tables, and interface statistics, while Netstat -a shows all active network connections, including listening and non-listening connections.
• Netstat provides detailed information about individual network connections, including the process ID of the application that initiated the connection, while Netstat -a offers a more comprehensive view of all network connections on the system.
• Netstat allows you to filter the output based on specific criteria, such as protocol type, port number, or IP address, while Netstat -a includes all active connections without any filtering.
• Netstat is useful for monitoring network activity and troubleshooting network connectivity issues, while Netstat -a is helpful for gaining a complete overview of all network connections on the system.

Conclusion

In conclusion, Netstat and Netstat -a are both valuable tools for monitoring network activity and troubleshooting network connectivity issues. While Netstat provides detailed information about individual network connections and allows for filtering the output based on specific criteria, Netstat -a offers a more comprehensive view of all network connections on the system, including listening and non-listening connections. Depending on your specific needs, you may choose to use either Netstat or Netstat -a to gain insights into network activity and identify potential security risks.