Check Docker

Python script to check various aspects of Docker and Docker Swarm. It can verify that the daemon is up, is a part of a Swarm, and if Swarm services are healthy.

The check-docker.py script is a re-implentation of check_docker using the native Docker Python SDK and combines it into a single command.

Sensu Go Asset

To use as an asset, clone this repository and create a tarball using make.

git clone https://github.com/KSU-Linux/check-docker.git
cd check-docker
make all

This will generate the files check-docker.tar.gz and sha512sum.txt. You will need to upload check-docker.tar.gz to a downloadable URL which you can then reference in a Sensu Go asset definition.

---
type: Asset
api_version: core/v2
metadata:
  name: check-docker
spec:
  builds:
    - url: https://example.com/check-docker.tar.gz
      sha512: ${SHA512SUM}
      filters:
        - entity.system.os == 'linux'
        - entity.system.arch == 'amd64'
    - url: https://example.com/check-docker.tar.gz
      sha512: ${SHA512SUM}
      filters:
        - entity.system.os == 'linux'
        - entity.system.arch == '386'

Docker Permissions for Sensu Go

In order for Sensu Go to run docker commands, add the user to the docker group on systems that will use the check.

gpasswd -a sensu docker

Usage Examples

Ping

This check will verify that the Docker daemon is up and repsonsive.

./check-docker.py --ping
OK: docker is up

Containers

This check will confirm that there is at least 1 container up and running.

./check-docker.py --containers
OK: 4 running containers

Minimum/Maximum Running Containers

You can modify the minimum and maximum running containers for the --containers check using --min and --max respectively.

./check-docker.py --containers --min 1 --max 4
OK: 4 running containers

Swarm

This check will check the node is part of a Swarm.

./check-docker.py --swarm
OK: Docker Swarm enabled

Manager

This check confirms that the node is a Swarm manager.

./check-docker.py --swarm-manager
OK: Node is a manager

Services

This check can be used to verify that one or more Swarm services are healthy.

./check-docker.py --swarm-service jirafeau_app traefik_proxy
OK: Docker Swarm service 'jirafeau_app' replicas 2/2; OK: Docker Swarm service 'traefik_proxy' replicas 2/2

All Services

This check verifies all services in the Swarm.

./check-docker.py --swarm-services
OK: Docker Swarm service 'jirafeau_app' replicas 2/2; OK: Docker Swarm service 'traefik_proxy' replicas 2/2