Monitor your home server using Prometheus, Grafana and Node Exporter

To keep track of your server’s health, it’s essential to have a monitoring solution. This guide uses Prometheus, Grafana, and Node Exporter – three open-source tools that together form a powerful monitoring stack.

Node Exporter is a lightweight exporter that collects hardware and OS metrics from your server (like CPU, memory, and disk usage) and makes them available to Prometheus.

Prometheus is a monitoring tool designed to collect, store, and query time-series data. It scrapes metrics from monitored systems and can alert you if certain conditions are met.

Grafana visualizes data from Prometheus, displaying metrics in dashboards that make it easier to understand trends and anomalies over time.

With these tools, you’ll be able to view server metrics in a Grafana dashboard and get insights into system performance, helping you detect issues before they become critical. This tutorial will walk you through the setup process.

First, make sure you have docker installed, including docker-compose. If not, you can follow the instructions here: https://alexmihai.rocks/2024/10/07/install-docker-on-your-ubuntu-home-server/ .

Create a folder that you are going to use for this docker compose stack. Mine is in ~/docker/monitoring.

Create a docker-compose.yml file inside the folder with the following contents:

services:
  prometheus:
    image: prom/prometheus:v2.54.1
    container_name: prometheus
    volumes:
      - ./prometheus:/etc/prometheus
      - prometheus-storage:/prometheus
    command:
      - '--web.enable-lifecycle'
      - '--config.file=/etc/prometheus/prometheus.yml'
    ports:
      - 9090:9090
    networks:
      - monitoring
    restart: unless-stopped

  grafana:
    image: grafana/grafana:11.2.2
    container_name: grafana
    ports:
      - 3000:3000
    volumes:
      - grafana-storage:/var/lib/grafana
    networks:
      - monitoring
    restart: unless-stopped

  node-exporter:
    image: prom/node-exporter:v1.8.2
    container_name: node-exporter
    volumes:
      - /:/host:ro,rslave
    command:
      - '--path.rootfs=/host'
    ports:
      - 9100:9100
    networks:
      - monitoring
    restart: unless-stopped

volumes:
  grafana-storage: {}
  prometheus-storage: {}

networks:
  monitoring: {}

Create a prometheus subfolder and inside it create a prometheus.yml file with the following contents:

global:
  scrape_interval: 15s  # Scrape every 15 seconds

scrape_configs:
  - job_name: 'prometheus'
    static_configs:
      - targets: ['localhost:9090']

  - job_name: 'node-exporter'
    static_configs:
      - targets: ['node-exporter:9100']

From the folder containing the docker-compose.yml file, run:

$ docker compose up -d

If all goes well, you’ll be able to access the following URLs:

http://<hostname/ip>:9100/ (http://localhost:9100/ if running on the local machine) – shows the Node Exporter UI, something like this:

http://<hostname/ip>:9090/ (http://localhost:9090/ if running on the local machine) – shows the Prometheus we UI; if you navigate to ‘Status’ – ‘Targets’, you should see 2 healthy targets: