Note:  For Manager Node, you must append  --force  to force the node to leave the cluster. 11.2.2 Initializing swarm mode The first node in swarm is called Manager leader. This node is responsible for advertising its  IP address. In our case, we use the  sc74cn03.pbm.ihost.com  (129.40.23.70) instance to act  as leader. (See Example 11-2.) Example 11-2 Initializing a swarm cluster admin@570e9473805e:~$  docker swarm init --advertise-addr 129.40.23.70 Swarm initialized: current node (1xk53pdq2ujayiea2vbfu3bs1) is now a manager. To add a worker to this swarm, run the following command: docker swarm join --token  SWMTKN-1-17aalrjaxjmlx43ytth47xb23enxaek0ris89826ane1d6o99z-1zzz4qvmc8bxhb2le3gulg3nx  129.40.23.70:2377 To add a manager to this swarm, run 'docker swarm join-token manager' and follow the  instructions. Note:  After issuing the preceding  docker swarm init  command, the master node is defined and  displays the command that allows you to add new worker nodes to the cluster. Make a note of it  because we use this command in the next steps. Example 11-2 demonstrates a command that adds another master node into the cluster. We  ran the command as instructed and Example 11-3 shows the output. Example 11-3 Getting the command to join manager nodes into the cluster admin@570e9473805e:~$  docker swarm join-token manager To add a manager to this swarm, run the following command: docker swarm join --token  SWMTKN-1-17aalrjaxjmlx43ytth47xb23enxaek0ris89826ane1d6o99z-cafuexvwlvojqhuosk7lqe07q  129.40.23.70:2377 11.2.3 Adding node manager to the cluster In this step, we add the second manager node to our swarm cluster. 1. Connect to  sc74cn09.pbm.ihost.com  zCX instance by using ssh (in other words,  ssh  admin@sc74cn09.pbm.ihost.com ). 2. Issue  docker swarm join , including the token for the manager node that you got in  Example 11-2. The following example shows the output: To join  sc74cn09.pbm.ihost.com  as master node, follow these steps: Example 11-4 Joining a manager node admin@01f543067055:~$  docker swarm join --token SWMTKN-1-17aalrjaxjmlx43ytth47xb23enxaek0ris89826ane1d6o99z-cafuexvwlvojqhuosk7lqe 07q 129.40.23.70:2377 This node joined a swarm as a manager. Chapter 11. Swarm on zCX  245