How to Use the Netstat Command

The netstat command is a powerful tool used to display network-related information in various operating systems. It provides information about network connections, routing tables, interface statistics, and more. Here’s how you can use the netstat command in Linux or MacOS:

1. Display all listening TCP and UDP ports:

netstat -tuln

This command will show a list of all TCP and UDP ports on which your system is listening for incoming connections, along with the associated process and PID.

2. Display network connections with the process ID (PID) and program name:

netstat -tup

This command will display all network connections along with the corresponding PID and program name that is associated with each connection.

3. Display network connections using a specific port number:

netstat -an | grep {{port_number}}

Replace {{port_number}} with the desired port number. This command will show all network connections that are using the specified port number.

4. Display network connections using a specific IP address:

netstat -an | grep {{ip_address}}

Replace {{ip_address}} with the desired IP address. This command will show all network connections that involve the specified IP address.

5. Display network connections in real-time:

netstat -antp

This command will continuously display network connections in real-time, updating the output as new connections are established or closed. It also shows the associated process and PID.

6. Display network interface statistics:

netstat -i

This command will show statistics for each network interface, including the number of packets sent and received, errors, collisions, and more.

Remember, while the netstat command is available on both Linux and macOS, there might be slight differences in the available options and flags. It’s always a good idea to refer to the netstat manual page specific to your operating system by running man netstat in the Terminal for more detailed information about the command and its options.