Docker Swarm Presentation

Prerequisites

Install virtualbox on your host

Get docker machine

Windows

if [[ ! -d "$HOME/bin" ]]; then mkdir -p "$HOME/bin"; fi && \
curl -L https://github.com/docker/machine/releases/download/v0.12.2/docker-machine-Windows-x86_64.exe > "$HOME/bin/docker-machine.exe" && \
chmod +x "$HOME/bin/docker-machine.exe"

curl -L https://github.com/docker/machine/releases/download/v0.12.2/docker-machine-`uname -s`-`uname -m` >/tmp/docker-machine &&
chmod +x /tmp/docker-machine &&
sudo cp /tmp/docker-machine /usr/local/bin/docker-machine

Building a docker swarm cluster

for i in 1 2 3; do
    docker-machine create -d virtualbox swarm-$i
done

Verify that your machines are up and running

docker-machine ls

The output should be something similar to

$ ./docker-machine.exe ls
NAME      ACTIVE   DRIVER       STATE     URL                         SWARM   DOCKER        ERRORS
swarm-1   -        virtualbox   Running   tcp://192.168.99.102:2376           v17.06.2-ce
swarm-2   -        virtualbox   Running   tcp://192.168.99.103:2376           v17.06.2-ce
swarm-3   -        virtualbox   Running   tcp://192.168.99.104:2376           v17.06.2-ce

Creating the cluster

eval "$(docker-machine env swarm-1)"

docker swarm init --advertise-addr $(docker-machine ip swarm-1)

##Connect to your docker machines through ssh

docker-machine ssh swarm-1

Adding the visualizer service

eval "$(docker-machine env swarm-1)"
docker service create \
  --name=visualizer \
  --publish=8000:8080/tcp \
  --constraint=node.role==manager \
  --mount=type=bind,src=/var/run/docker.sock,dst=/var/run/docker.sock \
  dockersamples/visualizer

Wait a bit and check the status of the visualizer service. Pulling dockersamples/visualizer:latest will speed things up!

docker service ls 

Once up open in your browser

echo http://$(docker-machine ip swarm-1):8000

Adding workers to the cluster

eval "$(docker-machine env swarm-1)"
JOIN_TOKEN=$(docker swarm join-token -q worker)

for i in 2 3; do
    eval "$(docker-machine env swarm-$i)"

    docker swarm join --token $JOIN_TOKEN \
        --advertise-addr $(docker-machine ip swarm-$i) \
        $(docker-machine ip swarm-1):2377
done

eval "$(docker-machine env swarm-1)"
docker node ls

Creating network

eval "$(docker-machine env swarm-1)"
docker network create -d overlay routing-mesh

Deploy a new service

eval "$(docker-machine env swarm-1)"
docker service create \
  --name=docker-routing-mesh \
  --publish=8080:8080/tcp \
  --network routing-mesh \
  --reserve-memory 20m \
  albertogviana/docker-routing-mesh:1.0.0

Testing the service

curl http://$(docker-machine ip swarm-1):8080
curl http://$(docker-machine ip swarm-2):8080
curl http://$(docker-machine ip swarm-3):8080

Scaling a service

docker service scale docker-routing-mesh=3

Calling a service

while true; do curl http://$(docker-machine ip swarm-1):8080; sleep 1; echo "\n";  done

Rolling updates

eval "$(docker-machine env swarm-1)"
docker service update \
  --update-failure-action pause \
  --update-parallelism 1 \
  --image albertogviana/docker-routing-mesh:2.0.0 \
  docker-routing-mesh

Calling a service

while true; do curl http://$(docker-machine ip swarm-1):8080/health; sleep 1; echo "\n";  done

Docker secret create

echo test | docker secret create my_secret -

Docker secret ls

docker secret ls

Deploy my secret

eval "$(docker-machine env swarm-1)"
docker service update \
  --update-failure-action pause \
  --update-parallelism 1 \
  --secret-add my_secret \
  --image albertogviana/docker-routing-mesh:2.0.0 \
  docker-routing-mesh

Drain a node

docker node update --availability=drain swarm-3

Listing nodes

docker node ls

Bring the node back

docker node update --availability=active swarm-3

Docker system info

docker system info

Docker and disk?

docker system df

Docker clean up

docker system prune