Scaling your service has usually been in the domain of system operators, which
installed servers and developers tweaking software when the load got high enough
to warrant scaling. Soon enough you’d be looking at tens or even hundreds of
instances which took a lot of time to manage. With the release of Docker 1.12,
you now have orchestration built in - you can scale to as many instances as your
hosts can allow. And setting up a docker swarm is easy-peasy.
