pinzon / docker-course-example

Simple excersice following a docker course

Docker/Swarm exercise

The result of this exercise is a example enviroment where you have several services in a Docker swarm. This project was developed using skills learned on Platzi.

The result it's the following enviroment:

In this case I used Play with Docker because it offers free resources for a limited time, enough to do testing.

Remember to change $repo_image with the name you want

1.- Clone this project.

git clone [e-mail]:pinzon/docker-course-example.git

2.- Build your image and test it.

docker build -t $repo_image .
docker run -it -p 3000:3000 $repo_image

3.- Push your image to docker hub.

docker push $repo_image

4.- Create a swarm without using the templates (1 manager and 4 workes).

#Command to initialize swarm
docker swarm init --advertise-addr eth0

#Command to join worker
docker swarm join --token $token

5.- Add a Visualizer to the swarm using a swarm manager. Visualizer needs the swarm state thats why you must bind the docker.socket to the container and run it from a manager.

docker service create -d --name viz -p 8080:8080 --constraint=node.role==manager --mount=type=bind,src=/var/run/docker.sock,dst=/var/run/docker.sock dockersamples/visualizer

6.- Start your services.

docker create service $repo_image --name stack_app1
docker create service $repo_image --name stack_app2

7.- Create overlay network to connect services.

docker network create --driver overlay proxy-net

8.- Update each service to 4 replicas, rollout mode and env variable.

docker service update --replicas 4  --env-add SECRET='Update secret of service 1' --update-parallelism 2 --label-add traefik.port=3000 --network-add proxy-net stack_app1 
docker service update --replicas 4  --env-add SECRET='Update secret of service 2' --update-parallelism 2 --label-add traefik.port=3000 --network-add proxy-net stack_app2 

9.- Create the Traefik service. Traefik also needs the swarm state thats why you must bind the docker.socket to the container and run it from a manager.

docker service create --name proxy --constraint=node.role==manager -p 80:80 -p 9090:8080 --mount type=bind,src=/var/run/docker.sock,dst=/var/run/docker.sock --network proxy-net traefik --docker --docker.swarmMode --docker.domain=test-service.com --docker.watch --api

10.- Test your environment with curl.

#In this case Play-with-docker needs the domain but with can still test the access to the services using Curl
curl -H "Host:stack-app1.test-service.com" http://localhost
curl -H "Host:stack-app2.test-service.com" http://localhost

Mounting a Docker Swarm Manager

11.- Create volume for portainer

docker volume create portainer_data

12.- Create the Portainer service

docker service create --name portainer -p 9000:9000 --constraint=node.role==manager --mount type=bind,src=/var/run/docker.sock,dst=/var/run/docker.sock --mount type=volume,src=portainer_data,dst=/data portainer/portainer -H unix:///var/run/docker.sock

Docker CleanUp service

This service cleans al images that are not being used by any container

Global mode means that it's going to run in all nodes

docker service create -d \
-e CLEAN_PERIOD=900 \
-e DELAY_TIME=600 \
--log-driver json-file \
--log-opt max-size=1m \
--log-opt max-file=2 \
--name=cleanup \
--mode global \
--mount type=bind,source=/var/run/docker.sock,target=/var/run/docker.sock \
meltwater/docker-cleanup

NOTE: Most of this project can be done with a single compose file.

TODO: Implement protheus.