If you’ve worked with Docker containers, you already understand how powerful they can be. But did you know you can exponentially up the power of Docker by creating a cluster of Docker hosts, called a Docker swarm? Believe it or not, this process is really simple. All you need is one machine to serve as a Docker swarm manager and a few Docker hosts to join the swarm as nodes.
I want to walk you through the process of enabling a Docker swarm manager and then joining two hosts as nodes. I will be demonstrating with the Ubuntu Server 16.04 platform for all machines. Do note this process will be very similar on nearly all Linux platforms. I will assume you already have Docker installed on all machines and will demonstrate with my manager at IP address 192.168.1.139 and my nodes at IP address (docker-node-1 at 192.168.1.177, docker-node-2 at 192.168.1.178, and ZOMBIE-KING at 192.168.1.162). Each node must also be running Docker.
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