Docker Engine is suitable for developing lightweight applications that run in Docker containers that are isolated from each other. Docker containers are able to provide their own networking and filesystem.
The Problem
Docker Engine (prior to native Swarm mode) was designed to run Docker containers that must be started separately. Consider the use case that multiple replicas or instances of a service need to be created. As client load on an application running in a Docker container increases, the application may need to be run on multiple nodes. A limitation of Docker ...
