Swarm mode

In version 1.12, Docker introduced the Swarm mode, built into its engine. To run a cluster, the user needs to execute two commands on each Docker host:

To enter Swarm mode:

$ docker swarm init

To add a node to the cluster:

$ docker swarm join  

Unlike Swarm, Swarm mode comes with service discovery, load balancing, security, rolling updates and scaling, and so on, built into the Docker engine itself. Swarm mode makes the management of the cluster easy since it does not require any orchestration tools to create and manage the cluster.