Real-Time VPS Monitoring with Netdata: CPU, RAM, Disk, and Application Metrics Dashboard

Netdata is an open-source, real-time monitoring agent that visualizes hundreds of system and application metrics in a built-in web dashboard — CPU, RAM, disk I/O, network, Nginx connections, MySQL queries, Docker containers, and more — with per-second granularity and zero configuration for most metrics. Unlike Prometheus + Grafana (which needs significant setup), Netdata works out of the box in 2 minutes.

Netdata vs Prometheus + Grafana

Step 1: Install Netdata

<code"># Official installer (handles all dependencies)
wget -O /tmp/netdata-install.sh https://get.netdata.cloud/kickstart.sh
sh /tmp/netdata-install.sh --stable-channel --no-updates

# Verify
sudo systemctl status netdata
curl http://localhost:19999/api/v1/info | python3 -m json.tool | head -20

Step 2: Secure Access with Nginx

Netdata’s dashboard runs on port 19999. Never expose this directly — proxy through Nginx with authentication:

<code">sudo nano /etc/nginx/sites-available/netdata

<code">server {
    listen 443 ssl http2;
    server_name monitor.yourdomain.com;

    ssl_certificate /etc/letsencrypt/live/monitor.yourdomain.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/monitor.yourdomain.com/privkey.pem;

    # Basic authentication
    auth_basic "Netdata Monitoring";
    auth_basic_user_file /etc/nginx/.netdata_htpasswd;

    location / {
        proxy_pass http://127.0.0.1:19999;
        proxy_http_version 1.1;
        proxy_set_header Host $host;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;

        # Compression for dashboard
        gzip on;
        gzip_types application/json text/plain;
    }
}

<code">sudo htpasswd -c /etc/nginx/.netdata_htpasswd admin
sudo ln -s /etc/nginx/sites-available/netdata /etc/nginx/sites-enabled/
sudo nginx -t && sudo systemctl reload nginx
sudo certbot --nginx -d monitor.yourdomain.com

Also bind Netdata to localhost only:

<code">sudo nano /etc/netdata/netdata.conf

<code">[web]
    bind to = 127.0.0.1

<code">sudo systemctl restart netdata

Step 3: What Netdata Monitors Automatically

Without any configuration, Netdata auto-discovers and monitors:

• System: CPU (per core), RAM, swap, load average, processes, context switches
• Disk: I/O operations, throughput, latency, utilization, space usage
• Network: Bandwidth per interface, packets, errors, TCP connections
• Nginx: Active connections, requests/second, reading/writing/waiting
• MySQL/MariaDB: Queries/second, slow queries, connections, replication
• Redis: Operations/second, memory usage, connected clients, keyspace
• PHP-FPM: Active processes, idle processes, request rate
• Docker: CPU and RAM per container
• systemd: Service state, restarts

Step 4: Configure Alerts

Netdata includes 200+ pre-configured alerts. Add your own or modify thresholds:

<code">sudo nano /etc/netdata/health.d/custom.conf

<code"># Alert when disk usage exceeds 85%
alarm: disk_space_usage
    on: disk.space
  lookup: average -10m percentage of used
    calc: $this
   every: 1m
    warn: $this > 80
    crit: $this > 90
    info: disk space usage is high

# Alert when RAM usage exceeds 90%
alarm: ram_usage
    on: system.ram
  lookup: average -5m percentage of used
    calc: $this
   every: 1m
    warn: $this > 85
    crit: $this > 95
    info: RAM usage is critically high

Step 5: Configure Telegram Notifications

<code">sudo nano /etc/netdata/health_alarm_notify.conf

<code"># Find and uncomment/modify:
SEND_TELEGRAM="YES"
TELEGRAM_BOT_TOKEN="your_telegram_bot_token"
DEFAULT_RECIPIENT_TELEGRAM="your_telegram_chat_id"

# Alert severity levels to notify on:
# critical: immediate action required
# warning: attention needed
# clear: alert resolved

<code">sudo systemctl restart netdata

# Test notification
sudo -u netdata /usr/libexec/netdata/plugins.d/alarm-notify.sh test telegram

Step 6: Tune Netdata for Low-RAM VPS

<code">sudo nano /etc/netdata/netdata.conf

<code">[global]
    # Reduce history (default 3600 seconds = 1 hour of per-second data)
    history = 1800       # 30 minutes — reduces RAM usage

    # Reduce memory pressure
    memory deduplication (ksm) = no   # Disable KSM on small VPS

    # Reduce update frequency (default 1 second)
    # update every = 2   # 2-second granularity saves CPU

[web]
    bind to = 127.0.0.1

[plugins]
    # Disable collectors you don't use
    # python.d = no   # Uncomment if not using Python-based collectors
    # node.d = no

Step 7: Multi-Server Monitoring with Netdata Parent

<code"># On child servers — stream data to parent
sudo nano /etc/netdata/stream.conf

<code">[stream]
    enabled = yes
    destination = parent.yourdomain.com:19999
    api key = YOUR_SHARED_API_KEY

<code"># On the parent server — receive streams from children
sudo nano /etc/netdata/stream.conf

<code">[YOUR_SHARED_API_KEY]
    enabled = yes
    history = 3600
    default memory mode = save
    health enabled by default = auto

Useful Netdata API Endpoints

<code"># Current CPU usage
curl -s http://localhost:19999/api/v1/data?chart=system.cpu&after=-60 | python3 -m json.tool

# All active alerts
curl -s http://localhost:19999/api/v1/alarms | python3 -m json.tool

# List all available charts
curl -s http://localhost:19999/api/v1/charts | python3 -m json.tool | grep '"id"' | head -30

# Export metrics in Prometheus format
curl -s http://localhost:19999/api/v1/allmetrics?format=prometheus | head -50

Getting Started

Netdata installs in 2 minutes on any Ubuntu VPS at VPS.DO and immediately provides per-second visibility into everything happening on the server. The 50–100 MB RAM footprint is appropriate for any VPS plan. For VPS troubleshooting — identifying which process caused a CPU spike 20 minutes ago, or what saturated the disk I/O — Netdata’s per-second historical granularity is invaluable.

Conclusion

Netdata provides instant, zero-configuration visibility into VPS health — CPU, RAM, disk, network, and application metrics at per-second granularity, in a built-in web dashboard, with 200+ pre-configured alerts. For teams that want immediate monitoring without the Prometheus + Grafana setup overhead, Netdata is the right tool. It pairs well with Uptime Kuma (external availability monitoring) and can stream metrics to a central Netdata parent server for multi-VPS visibility.