---
title: netstat Command Cheatsheet
description: "# The Linux `netstat` Command The Linux `netstat` command is a powerful networking tool used to display network connections, routing tables, interface statistics, masquerade connections, and multicast memberships. Though now often replaced by `ss`, it remains valuable in many Linux…"
url: "https://www.relianoid.com/resources/knowledge-base/misc/netstat-command-cheatsheet/"
updated: "2025-08-04"
category: Misc
---

# netstat Command Cheatsheet

# The Linux `netstat` Command

The Linux `netstat` command is a powerful networking tool used to display network connections, routing tables, interface statistics, masquerade connections, and multicast memberships. Though now often replaced by `ss`, it remains valuable in many Linux distributions for diagnosing network issues and monitoring system performance.

## Key Usage and Syntax of the `netstat` Command

The basic syntax of the `netstat` command is:

`netstat [OPTIONS]`

- **OPTIONS**: Flags to control the behavior and output of `netstat`.

## `netstat` Command Cheatsheet Table

| Command | Description |
| --- | --- |
| `netstat` | Displays active connections, routing tables, and interface statistics. |
| `netstat -t` | Shows only TCP connections. |
| `netstat -u` | Shows only UDP connections. |
| `netstat -l` | Displays listening ports and sockets. |
| `netstat -r` | Displays the routing table. |
| `netstat -i` | Displays network interface statistics. |
| `netstat -s` | Shows summary statistics for each protocol. |
| `netstat -p` | Displays the PID and program name for connections. |

## Common Use Cases

### View Active Connections

`netstat`

Displays all active network connections on the system.

### Show TCP Connections

`netstat -t`

Filters the output to display only TCP connections.

### Monitor Listening Ports

`netstat -l`

Lists all ports that are currently in the listening state.

### View Routing Table

`netstat -r`

Displays the system's routing table, useful for diagnosing routing issues.

### Check Process-Specific Connections

`netstat -p`

Shows the process ID (PID) and program name associated with each connection.

## Advanced Usage

### Interface Statistics

`netstat -i`

Displays detailed statistics about network interfaces, including transmitted and received packets.

### Summary Protocol Statistics

`netstat -s`

Provides a summary of network statistics, grouped by protocol (TCP, UDP, ICMP, etc.).

### Filter by Address

Combine with `grep` to filter connections by address:

`netstat -an | grep 192.168.1.1`

## Using `netstat` with RELIANOID Solutions

In RELIANOID’s infrastructure, the `netstat` command is useful for diagnosing connectivity, analyzing load balancer performance, and monitoring system operations.

### Monitor Load Balancer Connections

`netstat -tuln | grep ":80"`

Displays connections on port 80 to monitor HTTP traffic through the load balancer.

### Analyze Backend Service Traffic

Track connections to backend servers:

`netstat -an | grep 10.0.0.5`

This shows connections to the backend server at `10.0.0.5`.

### Debug Proxy Configuration

Verify that proxy services are running and accepting connections:

`netstat -l | grep ":443"`

### Investigate Network Performance

Use `netstat` to collect statistics on dropped packets or retransmissions to diagnose performance bottlenecks:

`netstat -s | grep -i "retrans"`

## Security Considerations

Always ensure that sensitive information, such as IP addresses and PIDs, is handled securely. Use access controls to prevent unauthorized users from running network diagnostics.

## Summary

The `netstat` command is a foundational tool for network management and troubleshooting. Though increasingly supplemented by tools like `ss`, its ease of use and versatility make it a staple for network professionals. RELIANOID incorporates `netstat` in its diagnostic and monitoring workflows to maintain robust, high-performance networking solutions.

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