Introduction

In this blog, we will walk through how to monitor containers using Prometheus and cAdviser.

cAdvisor (short for container Advisor) analyzes and exposes resource usage and performance data from running containers. cAdvisor exposes Prometheus metrics out of the box. The container metrics will be collected by cAdvisor and scraped by Prometheus.

Pre-requisites

• User with sudo privileges
• Docker installed

Steps

Step 1

Configure Prometheus to scrape metrics from cAdvisor. Create a prometheus.yml file and paste below code:

scrape_configs:
- job_name: cadvisor
  scrape_interval: 5s
  static_configs:
  - targets:
    - cadvisor:8080

Step 2

Now, in the same directory where you have created prometheus.yml, create adocker-compose.yml file defining both prometheus and cAdviser services. Copy and paste below in the file:

version: '3'
services:
  prometheus:
    image: prom/prometheus:latest
    container_name: prometheus
    ports:
      - 9090:9090
    command:
      - --config.file=/etc/prometheus/prometheus.yml
    volumes:
      - ./prometheus.yml:/etc/prometheus/prometheus.yml
    depends_on:
      - cadvisor

  cadvisor:
    image: google/cadvisor:latest
    container_name: cadvisor
    ports:
      - 8080:8080
    volumes:
      - /:/rootfs:ro
      - /var/run:/var/run:rw
      - /sys:/sys:ro
      - /var/lib/docker:/var/lib/docker:ro

Step 3

Run docker-compose up -d to deploy the services and make it running in the background.

To verify the running containers, run docker ps. you can also access prometheus web dashboard on [your-public-ip]:9090 and cAdviser on [your-public-ip]:8080