Docker Swarm

Hosts can be managers, which handle scheduling and the overall state of the swarm in addition to hosting containers, or workers, which only host containers. Recommend an odd number of managers, usually 3-5. Managers spin up tasks (read: containers) on hosts within the swarm as appropriate.

Non-swarm mode is backwards compatible, so any swarm-specific code will just be ignored when running on a host that isn't part of a swarm.

Start a new swarm, specifying which IP will be used within the swarm:

docker swarm init --advertise-addr 172.31.12.161:2377 --listen-addr 172.31.12.161:2377