docs/engine/getstarted-voting-app/create-swarm.md

description	keywords	title
Setup for voting app example	multi-container, services, swarm mode, cluster, voting app	Create a swarm

Now, we'll transform our Docker machines into a swarm.

1. Log on to the manager.

    $ docker-machine ssh manager
                          ##         .
                    ## ## ##        ==
                 ## ## ## ## ##    ===
             /"""""""""""""""""\___/ ===
        ~~~ {~~ ~~~~ ~~~ ~~~~ ~~~ ~ /  ===- ~~~
             \______ o           __/
               \    \         __/
                \____\_______/
     _                 _   ____     _            _
    | |__   ___   ___ | |_|___ \ __| | ___   ___| | _____ _ __
    | '_ \ / _ \ / _ \| __| __) / _` |/ _ \ / __| |/ / _ \ '__|
    | |_) | (_) | (_) | |_ / __/ (_| | (_) | (__|   <  __/ |
    |_.__/ \___/ \___/ \__|_____\__,_|\___/ \___|_|\_\___|_|
   
    WARNING: this is a build from test.docker.com, not a stable release.
   
    Boot2Docker version 1.13.0-rc6, build HEAD : 5ab2289 - Wed Jan 11 23:37:52 UTC 2017
    Docker version 1.13.0-rc6, build 2f2d055
   

2. Initialize a swarm.

    docker@manager:~$ docker swarm init --advertise-addr 192.168.99.100
    Swarm initialized: current node (ro5ak9ybe5qa62h7r81q29z0k) is now a manager.
   

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

    docker swarm join \
    --token SWMTKN-1-4bk4romozl9ap5xpt0it6gzdwabtezs399go3fyaw1hy8t1kam-0xnovvmchc4wfe7xmh85faiwe \
    192.168.99.100:2377

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

Add a worker node to the swarm

1. Log into the worker machine.

    $ docker-machine ssh worker
                            ##         .
                      ## ## ##        ==
                   ## ## ## ## ##    ===
               /"""""""""""""""""\___/ ===
          ~~~ {~~ ~~~~ ~~~ ~~~~ ~~~ ~ /  ===- ~~~
               \______ o           __/
                 \    \         __/
                  \____\_______/
     _                 _   ____     _            _
    | |__   ___   ___ | |_|___ \ __| | ___   ___| | _____ _ __
    | '_ \ / _ \ / _ \| __| __) / _` |/ _ \ / __| |/ / _ \ '__|
    | |_) | (_) | (_) | |_ / __/ (_| | (_) | (__|   <  __/ |
    |_.__/ \___/ \___/ \__|_____\__,_|\___/ \___|_|\_\___|_|
   
      WARNING: this is a build from test.docker.com, not a stable release.
   
    Boot2Docker version 1.13.0-rc6, build HEAD : 5ab2289 - Wed Jan 11 23:37:52 UTC 2017
    Docker version 1.13.0-rc6, build 2f2d055
   

2. On the worker, run the join command given as the output of the swarm init command you ran on the manager.

    docker@worker:~$ docker swarm join \
    >     --token SWMTKN-1-4bk4romozl9ap5xpt0it6gzdwabtezs399go3fyaw1hy8t1kam-0xnovvmchc4wfe7xmh85faiwe \
    >     192.168.99.100:2377
    This node joined a swarm as a worker.
   

If you don't have the command, run docker swarm join-token worker on a manager node to retrieve the join command for a worker for this swarm.

List the nodes in the swarm

Log into the manager and run docker node ls.

  docker@manager:~$ docker node ls
  ID                           HOSTNAME  STATUS  AVAILABILITY  MANAGER STATUS
  dlosx9b74cgu4lh2qy54ebfp8    worker    Ready   Active
  ro5ak9ybe5qa62h7r81q29z0k *  manager   Ready   Active        Leader

Deploy the app

In these steps, you'll use the docker-stack.yml file to deploy the application to the swarm you just created. To deploy an app deployed to a swarm You'll run the deploy command from the manager.

The docker-stack.yml file must be located on a manager for the swarm where you want to deploy the application stack.

1. Get docker-stack.yml either from the lab or by copying it from the example given here.

2. Copy docker-stack.yml from your host machine onto the manager.

    $ docker-machine scp ~/sandbox/voting-app/docker-stack.yml manager:/home/docker/.
    docker-stack.yml                                                                      100% 1558     1.5KB/s   00:00
   

3. Log onto the manager.

    $ docker-machine ssh manager
   

4. Check to make sure the .yml file is there.

    docker@manager:~$ ls
    docker-stack.yml  log.log
   

   You can use vi or other text editor to inspect it.

5. Deploy the application stack based on the .yml.

    docker@manager:~$ docker stack deploy --compose-file docker-stack.yml vote
    Creating network vote_default
    Creating network vote_backend
    Creating network vote_frontend
    Creating service vote_result
    Creating service vote_worker
    Creating service vote_visualizer
    Creating service vote_redis
    Creating service vote_db
    Creating service vote_vote
   

6. Verify that the stack deployed as expected with docker stack services <appName>.

    docker@manager:~$ docker stack services vote
    ID            NAME             MODE        REPLICAS  IMAGE
    0y3q6lgc0drn  vote_result      replicated  2/2       dockersamples/examplevotingapp_result:before
    fvsaqvuec4yw  vote_redis       replicated  2/2       redis:alpine
    igev2xk5s3zo  vote_worker      replicated  1/1       dockersamples/examplevotingapp_worker:latest
    vpfjr9b0qc01  vote_visualizer  replicated  1/1       dockersamples/visualizer:stable
    wctxjnwl22k4  vote_vote        replicated  2/2       dockersamples/examplevotingapp_vote:before
    zp0zyvgaguox  vote_db          replicated  1/1       postgres:9.4
   

What's next?

In the next step, we'll deploy the voting app.