7.3 Netdata Tutorial

Overview

Netdata is a real-time performance monitoring and visualization tool that tracks both system-level and application-level metrics.

Key features:

• Real-time monitoring: Refreshes system and application metrics every second
• Rich visualizations: Provides web dashboards, charts, and alerts
• Lightweight: Low overhead with minimal impact on production systems
• Multi-platform support: Linux, BSD, Docker, and more

Typical use cases:

• Monitoring system resources (CPU, memory, disk, network)
• Analyzing service performance (web servers, databases, etc.)
• Detecting anomalies and setting alerts

Official documentation: https://learn.netdata.cloud

Netdata Installation

sudo apt update
sudo apt install netdata

Starting and Accessing Netdata

Start the Service

sudo systemctl start netdata
sudo systemctl enable netdata

Stop and Restart

sudo systemctl stop netdata
sudo systemctl restart netdata

Access the Web Interface

Local Access

Netdata listens on port 19999 by default. After installation, access it via your browser at:

http://localhost:19999/

The web interface displays real-time metrics for CPU, memory, disk, network, processes, etc.

LAN Access

To allow other machines on your local network to access Netdata, modify the configuration file:

sudo vim /etc/netdata/netdata.conf

Locate the configuration line:

bind socket to IP = 127.0.0.1

Change it to:

bind socket to IP = 0.0.0.0

Restart the service for changes to take effect:

sudo systemctl restart netdata

Access Netdata from other machines using http://<server-IP>:19999/.

Key Monitoring Metrics

By default, Netdata automatically tracks:

Category	Example Metrics
CPU	Usage, load, frequency, context switches
Memory	Usage, cache, swap space
Disk	I/O read/write rates, latency, disk queues
Network	Bandwidth, traffic, packet loss
System	Process count, file handles, user login info
Services	Web servers, databases, containers (requires plugins)

Process Monitoring

The web interface shows CPU, memory, and thread counts for each process, with sorting and filtering options.

Application monitoring (via plugins)

Plugins extend Netdata to track applications like:

• Nginx / Apache
• MySQL / PostgreSQL
• Docker / Kubernetes

Once installed, these metrics appear automatically in the web interface.

Netdata Configuration

Configuration File Location

Netdata's main configuration file is located at:

/etc/netdata/netdata.conf

Common configuration options:

• bind socket to IP = 127.0.0.1 Indicates the target monitoring address for the web interface.
  • Default 127.0.0.1: Local access only
  • Change to 0.0.0.0: Allow access from any LAN IP
• run as user = netdata Specifies the user account that runs the Netdata service (default: netdata). It operates with minimal privileges to improve security.
• web files owner = root Sets ownership of web interface files (typically root) to prevent unauthorized modifications.
• web files group = root Specifies the group for web interface files (default: root), used together with owner.

Restart the service after configuration changes:

sudo systemctl restart netdata

Alert Configuration

Alert configuration files are located in:

/etc/netdata/health.d/

Example custom threshold:

alarm: high_cpu
on: system.cpu
calc: $usage > 90
every: 10s
warn: $usage > 80
info: CPU usage exceeds threshold

This triggers an alert when CPU usage exceeds 90%, with notifications sent via email or Slack.

Advanced Features

Multi-node Monitoring

• Supports master/child mode.
• The master node collects data from multiple child nodes for centralized management.

Data Export

• Works with Prometheus, Graphite, and other data collectors.
• Lets you access historical data and create custom reports through the API.