Build a Complete Prometheus Monitoring Stack with Grafana: Step‑by‑Step Docker Setup

Prometheus is a powerful monitoring solution that provides data collection, storage, processing, visualization, and alerting.

Key Components

Prometheus consists of four main modules: Prometheus Server, Exporter, Alertmanager, and a visualization component.

Prometheus Server pulls data from Exporters, stores it, and offers the PromQL query language.

Exporter collects performance metrics from hosts or containers and exposes them via an HTTP endpoint.

Alertmanager receives alerts based on monitoring data and sends notifications according to predefined rules.

The visualization component originally built into Prometheus has been largely superseded by Grafana, which integrates seamlessly for rich dashboards.

Hands‑On Lab

1. Environment Setup

The lab monitors two hosts, collecting host‑level metrics and optionally container metrics using appropriate dashboards.

The following Docker containers are deployed:

Prometheus Server (running on 192.168.0.102)

Node Exporter – gathers host hardware and OS data.

cAdvisor – gathers container metrics.

Grafana – visualizes the collected data.

2. Run Node Exporter

docker run -d --name node-exporter -p 9100:9100 \
 -v "/proc:/host/proc:ro" -v "/sys:/host/sys:ro" -v "/:/rootfs:ro" \
 --restart=always --net="host" \
 prom/node-exporter \
 --path.procfs /host/proc --path.sysfs /host/sys \
 --collector.filesystem.ignored-mount-points "^/(sys|proc|dev|host|etc)($|/)"

Using --net="host" allows direct communication between Node Exporter and Prometheus Server.

3. Run cAdvisor

docker run -v /:/rootfs:ro -v /var/run:/var/run:rw \
 -v /sys:/sys:ro -v /var/lib/docker:/var/lib/docker:ro \
 -p8080:8080 -t --name cadvisor --net="host" \
 google/cadvisor:latest

Again, --net="host" enables direct communication with Prometheus.

4. Run Prometheus Server

docker run -d -p 9090:9090 \
 -v /root/prometheus.yml:/etc/prometheus/prometheus.yml \
 --name prometheus --net host \
 prom/prometheus

The prometheus.yml configuration defines a global scrape interval of 15 seconds and specifies static targets for the Exporters.

# my global config
global:
  scrape_interval: 15s
  evaluation_interval: 15s

alerting:
  alertmanagers:
    - static_configs:
        - targets:
          - alertmanager:9093

scrape_configs:
  - job_name: 'prometheus'
    scrape_interval: 5s
    static_configs:
      - targets: ['localhost:9090','localhost:8080','localhost:9100','192.168.0.101:9100','192.168.0.101:8080']

Access http://192.168.0.102:9090 , go to the Status → Targets page; all targets should show UP , confirming successful data collection.

5. Install Grafana

docker run -d -p 3000:3000 \
 -e "GF_SERVER_ROOT_URL=http://grafana.server.com" \
 -e "GF_SECURITY_ADMIN_PASSWORD=admin@123" \
 --net="host" grafana/grafana

The -e "GF_SECURITY_ADMIN_PASSWORD=admin@123" flag sets the Grafana admin password.

Open http://192.168.0.102:3000 , add Prometheus as a data source, and import a ready‑made dashboard JSON (e.g., a host‑only dashboard) to visualize the metrics.