Create a swarm

Now, we’ll add our Docker machines to a swarm.

Initialize the swarm

1. Log into 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-rc7, build HEAD : b2cde29 - Sat Jan 14 00:29:39 UTC 2017
   Docker version 1.13.0-rc7, build 48a9e53
   docker@manager:~$ ls
   log.log
   docker@manager:~$ docker swarm init --advertise-addr 192.168.99.100
   Swarm initialized: current node (2tjrasfqfu945b7n4753374sw) is now a manager.
   

2. Initialize a swarm.

   The command to initialize a swarm is:

   docker swarm init --advertise-addr <MANAGER-IP>
   

   Use the IP address of the manager. (See Verify machines are running and get IP addresses).

   docker@manager:~$ docker swarm init --advertise-addr 192.168.99.100
   Swarm initialized: current node (2tjrasfqfu945b7n4753374sw) is now a manager.
   
   To add a worker to this swarm, run the following command:
   
       docker swarm join \
       --token SWMTKN-1-144pfsupfo25h43zzr6b6bghjson8uedxjsndo5vuehqlyarsk-9k4q84axm008whv9zl4a8m8ct \
       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-rc7, build HEAD : b2cde29 - Sat Jan 14 00:29:39 UTC 2017
   Docker version 1.13.0-rc7, build 48a9e53
   

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-1-144pfsupfo25h43zzr6b6bghjson8uedxjsndo5vuehqlyarsk-9k4q84axm008whv9zl4a8m8ct \
   >     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 (e.g., docker-machine ssh manager) and run docker node ls.

  docker@manager:~$ docker node ls
ID                           HOSTNAME  STATUS  AVAILABILITY  MANAGER STATUS
2tjrasfqfu945b7n4753374sw *  manager   Ready   Active        Leader
syc46yimgtyz9ljcsfqiurvp0    worker    Ready   Active        

What’s next?

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