[Linux] C Shell (csh) netstat Uso: Display network connections and statistics

Overview

The netstat command is a powerful tool used to display network connections, routing tables, interface statistics, and more. It helps users monitor network activity and diagnose network issues.

Usage

The basic syntax of the netstat command is as follows:

netstat [options] [arguments]

Common Options

• -a: Show all active connections and listening ports.
• -n: Display addresses and port numbers in numerical form rather than resolving them to hostnames.
• -r: Display the routing table.
• -i: Show network interface statistics.
• -p: Show the process ID and name associated with each connection.

Common Examples

Here are some practical examples of using the netstat command:

1. Display all active connections:

   netstat -a
   

2. Show active connections with numerical addresses:

   netstat -an
   

3. View the routing table:

   netstat -r
   

4. List network interface statistics:

   netstat -i
   

5. Show connections along with the associated process IDs:

   netstat -p
   

Tips

• Use the -n option to speed up the output by avoiding DNS lookups, especially useful on busy networks.
• Combine options for more detailed output, such as netstat -anp to see all connections with process information.
• Regularly check your network connections to identify any unauthorized access or unusual activity.