Alert slack with alert manager in Docker environment

What to do in this article

I'm using docker-compose to launch the Prometheus and alertmanager containers and see the alerts I received in Slack.

environment

In the docker environment, create a container that runs the following applications.

• Prometheus: 2.23.0
• alertmanager: 0.21.0

Environment

In this article, we will use docker-compose to build Prometheus and alertmanager. First, create the file structure as follows.

docker-compose.yaml
prometheus
-- prometheus.yaml
-- alert_rules.yaml
alertmanager
-- alertmanager.yaml

Next, build the docker network with docker network create --subnet = 172.19.0.0/19 prom_net. After building the configuration file and docker nework, build the docker environment with the following docker-compose.yaml.

docker-compose.yaml

version: '2.2'
# define services
services:
  prometheus:
    image: prom/prometheus
    container_name: prometheus
    volumes: 
       - ./prometheus:/etc/prometheus
    command: "--config.file=/etc/prometheus/prometheus.yaml --storage.tsdb.retention.time=10m"
    ports: 
      - 9090:9090      
    restart: "no"
  alertmanager:
    image: prom/alertmanager
    container_name: alertmanager
    volumes:
      - ./alertmanager:/etc/alertmanager
    command: "--config.file=/etc/alertmanager/alertmanager.yaml"
    ports:
      - 9093:9093
    restart: "no"

# define network
networks:  
  default:
    external:
      name: prom_net

Prometheus settings

The configuration file of Prometheus is as follows. For slack_api_url:'<Your channel on Slack>', enter the webhook URL of any Slack you created.

prometheus.yaml

global:
  slack_api_url: '< Your channel on Slack >'

route:
  receiver: slack
  routes:
  - match:
      receiver: 'slack'


receivers:
  - name: slack
    slack_configs:
    - channel: '< Channel Name >'
      text: '< Optional Text>'

Next, Prometheus is set to send alerts about Mertric. We have selected appropriate Metrics for the conditions for sending alerts, so please choose your favorite Metrics.

alert_rule.yaml

groups:
- name: prometheus_build
  rules:
  - alert: test
    expr: prometheus_build_info == 1
    for: 10s
    labels:
      severity: notice
    annotations:
      text: testsing alert

test

Finally, launch each application's container and see the alerts sent by Prometheus and Slack. By the way, the following is the command to start / stop the container configured with docker-compose. docker-compose up docker-compose down

Prometheus Below, you can see from the image that the alert is being sent under the conditions set in alert_rule.yaml.

Slack You can see that the alert displayed by Prometheus can be received by Channle of Slack.

Impressions

I used Prometheus and alertmanager to check if I could receive alerts in Slack. In the future, I would like to send an alert to Elasticsearch and configure it so that Kibana can check the log. In this article, I used Slack's Channel to see if I could send alerts.