the setup is easy, actually. we only need to have 2 linux machines with docker installed.

1. we execute this command on the first machine:

   docker swarm init 

   or if you have multiple interfaces with multiple ip's you get error when you wanna init the cluster, you should choose one interface/ip and init using that address as --advertise-addr, like this:

   docker swarm init --advertise-addr masterip

   which outputs a join command for the worker node to join the swarm cluster:

   docker swarm join --token mytoken masterip:2377

2. check if the node(s) have successfully joined the cluster.

   docker node ls

3. deploy the tomcat stack on the cluster.

   docker stack deploy -c stack.yaml tomcat-stack

4. check status of services and containers of tomcat-stack in the cluster with these two commands.

   docker stack services tomcat-stack

   docker stack ps tomcat-stack

5. profit.