Docker Swarm Mode
Docker Engine v1.12 was released in July 2016. It is the most significant version since v1.9. Back then, we got Docker networking that, finally, made containers ready for use in clusters. With v1.12, Docker is reinventing itself with a whole new approach to cluster orchestration. Say goodbye to Swarm as a separate container that depends on an external data registry and welcome the new Docker Swarm or Swarm Mode. Everything you'll need to manage your cluster is now incorporated into Docker Engine. Swarm is there. Service discovery is there. Improved networking is there. That does not mean that we do not need additional tools. We do. The major difference is that Docker Engine now incorporates all the "essential" (not to say minimal) tools we need.
The old Swarm (before Docker v1.12) used fire-and-forget principle. We would send a command to Swarm master, and it would execute that command. For example, if we would send it something like docker-compose scale go-demo=5
, the old...