Docker for Rails Developers

Our First (Single Node) Swarm

It’s time to dive deeper into Swarm and start getting our hands dirty.

Previously, we created a plain-vanilla Docker instance: local-vm-1. To turn our instance into a swarm, we have to initialize it explicitly. With our CLI targeting our new instance, we can do this by running:

$ docker swarm init --advertise-addr <IP address of instance>

where <IP address of instance>, in our case, is local-vm-1’s public IP address. We can easily find that out by rerunning:

$ docker-machine ls
NAME         …   …   …   URL                          …   …   …
local-vm-1   *   …   …   tcp://192.168.99.100:2376        …

The IP address of the instance is listed in the “URL” column. For me, the IP address is 192.168.99.100, but yours will differ. ...