1. Pre-Flight Checks

1.1. Docker

Let’s check to make sure docker and other components are installed and working correctly. First, check to make sure docker is installed.

1docker --version

You should see an output that looks like the following.

Docker version 19.03.2, build 6a30dfca03

Now, let’s make sure we are able to run the busybox container.

docker run busybox echo "hello, world!"

The command above simply echos hello, world! back to the console.

1.2. Swarm

1.2.1. Initialization

Initialize swarm.

1docker swarm init

You should see an output as follows.

Swarm initialized: current node (muo6bizx5z19kny0gswqm8jq4) is now a manager.

To add a worker to this swarm, run the following command:

    docker swarm join --token SWMTKN-1-3qo8eradxo3oy2tjzc0odurhumk4nlpt9eoeg2gq5dwl2sh88o-bc6fpa8qeh5bsn3l0kdfip2qf 10.0.2.15:2377

To add a manager to this swarm, run 'docker swarm join-token manager' and follow the instructions.

1.2.2. Service creation

Now let’s create a toy service. This service uses the apline:3.5 container to ping the Google domain name servier 8.8.8.8.

docker service create --name demo alpine:3.5 ping 8.8.8.8

The output should look like the following.

av2o3juacixl7zwr36wd10zzg
overall progress: 1 out of 1 tasks
1/1: running
verify: Service converged

To see which services are running.

docker service ps demo

To see the logs of a service.

docker service logs demo

To stop the service.

docker service rm demo