docker study notes: Prometheus+cAdvisor builds container monitoring

Prometheus+cAdvisor container monitoring

Introduction

Prometheus

官网Prometheus - Monitoring system & time series database

The second project of the CNCF Cloud Native Foundation

cAdvisor

cAdvisor (Container Advisor) is a container monitoring tool open sourced by Google, which can be used to monitor the usage and performance of container resources. It runs as a daemon and is used to collect, aggregate, process and export information about running containers. Specifically, for each container, this component records its resource isolation parameters, historical resource usage, histograms of complete historical resource usage, and network statistics.

cAdvisor itself supports Docker containers, and also provides support for other types of containers as much as possible, striving to be compatible and adaptable to all types of containers.

The officially recommended software for collecting data for Prometheus can obtain the resource usage of the host and the resource usage of the container.

Build ideas

The redis container is used as the monitored container, Cadvisor collects it, and Prometheus is used as the data source.

Build Prometheus+cAdvisor monitoring container

1. Pull the Prometheus image

[root@docker harbor]# docker pull prom/prometheus

2. Start the prometheus container

[root@docker harbor]# docker run -d -p9090:9090 --name myprom-1 prom/prometheus

3.Web page access

4. Copy the Prometheus configuration file from the container, place it under /myprom/, and stop running prometheus to prevent subsequent port occupation when the Prometheus container is enabled.

[root@docker harbor]# mkdir /myprom
[root@docker harbor]# cd /myprom/
[root@docker myprom]# ls
[root@docker myprom]# docker cp myprom-1:/etc/prometheus/prometheus.yml .
Successfully copied 2.56kB to /myprom/.
[root@docker myprom]# ls
prometheus.yml
[root@docker myprom]# docker stop myprom-1

5. Modify the prometheus.yml configuration file and add the monitored container cAdvisor as the target container

[root@docker myprom]# vim prometheus.yml

global:
alerting:
  alertmanagers:
    - static_configs:
        - targets:
rule_files:
scrape_configs:
  - job_name: "prometheus"
    static_configs:
      - targets: ["localhost:9090"]
  - job_name: cadvisor
    scrape_interval: 5s
    static_configs:
      - targets:
        - cadvisor:8080

6. Use docker compose to start redis, Prometheus, and cadvisor

[root@docker myprom]# vim docker-compose.yml

version: '3.2'
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:ro
    depends_on:
    - cadvisor
  cadvisor:
    image: gcr.io/cadvisor/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
    depends_on:
    - redis
  redis:
    image: redis:latest
    container_name: redis
    ports:
    - 6379:6379

Since the cadvisor image cannot be downloaded in China, you need to prepare it yourself.

/var/lib/docker/:/var/lib/docker:ro All docker data is mounted to cadvisor, so cadvisor can monitor the container

7. Upload the prepared cadvisor image to /myprom in Linux and import the image

[root@docker myprom]# ls
cadvisor.tar  docker-compose.yml  prometheus.yml
[root@docker myprom]# docker load -i cadvisor.tar 

8. Start docker compose

[root@docker myprom]# docker compose up -d
[root@docker myprom]# docker ps

Prometheus, cadvisor, and redis have all been started successfully

If an error is reported, it is likely that the previously started Prometheus occupies port 9090. Just docker stop to stop the previous container.

9. Web page access cadvisor, prometheus

Build successfully!