What Is the netstat Command in Linux?¶

Introduction¶

The netstat command shows legacy network connection and routing information. It is useful for beginners, Linux administrators, DevOps engineers, and RHCSA students because it solves practical terminal tasks.

What the Command Does¶

Use netstat to work with the specific Linux object it manages. Before changing anything, identify the target and run a read-only check when possible.

Basic Syntax¶

netstat OPTIONS

The syntax includes the command, any options, and the target object.

Common Options¶

• -t: show TCP.
• -u: show UDP.
• -l: show listening sockets.

Practical Examples¶

netstat -tuln
netstat -rn
netstat -tulpn
netstat -an | grep 443

Verification command:

netstat -s

Example output:

tcp        0      0 0.0.0.0:22        0.0.0.0:*        LISTEN

When to Use This Command¶

Use netstat on older systems or when legacy documentation expects it. On modern RHEL systems, prefer ss from the iproute package when available.

Common Mistakes¶

• Assuming netstat is installed on minimal systems.
• Using netstat by habit when ss gives clearer modern output.
• Forgetting -n, which can slow output while names are resolved.

Quick Reference¶

netstat -tuln
netstat -rn
netstat -s

Related Guides¶

• netstat examples
• netstat listening ports explained
• netstat vs ss
• netstat interview questions

Summary¶

The netstat command is safest when you understand the target, choose the right option, and verify the result with a separate command.