Docker swarm setup multiple VMs on localhost using vagrant

install_docker.sh

#!/bin/bash

# This creates me a new GnuPG directory to work with (so my personal ~/.gnupg doesn’t get cluttered with this new key), downloads Docker’s signing key from the keyserver gossip network (verifying the fetched key via the full fingerprint I’ve provided), exports the key into APT’s keystore, then cleans up the leftovers
export GNUPGHOME="$(mktemp -d)"
gpg --keyserver ha.pool.sks-keyservers.net --recv-keys 58118E89F3A912897C070ADBF76221572C52609D
#gpg --export --armor 58118E89F3A912897C070ADBF76221572C52609D | tee /etc/apt/trusted.gpg.d/docker.gpg.asc
gpg --export 58118E89F3A912897C070ADBF76221572C52609D | tee /etc/apt/trusted.gpg.d/docker.gpg
rm -rf "$GNUPGHOME"
echo "deb http://apt.dockerproject.org/repo ubuntu-$(lsb_release -cs) main" | tee /etc/apt/sources.list.d/docker.list

apt-key update
apt-get update
apt-get install -y --no-install-recommends linux-image-extra-$(uname -r) linux-image-extra-virtual

# set a storage driver
mkdir -p /etc/docker
echo "{\"storage-driver\": \"aufs\"}" | tee /etc/docker/daemon.json

#cgroup_enable=memory – enable “memory accounting” for containers (allows docker run --memory for setting hard memory limits on containers)
#swapaccount=1 – enable “swap accounting” for containers (allows docker run --memory-swap for setting hard swap memory limits on containers)
#systemd.legacy_systemd_cgroup_controller=yes – newer versions of systemd may disable the legacy cgroup interfaces Docker currently uses; 
sed -i '/GRUB_CMDLINE_LINUX_DEFAULT/c\GRUB_CMDLINE_LINUX_DEFAULT="cgroup_enable=memory swapaccount=1 systemd.legacy_systemd_cgroup_controller=yes"' /etc/default/grub

apt-get install -y --no-install-recommends docker-engine

# usermod -aG docker "$(id -un)"
usermod -aG docker ubuntu

docker version
docker info
reboot

Vagrantfile

# -*- mode: ruby -*-
# vi: set ft=ruby :

# All Vagrant configuration is done below. The "2" in Vagrant.configure
# configures the configuration version (we support older styles for
# backwards compatibility). Please don't change it unless you know what
# you're doing.
Vagrant.configure(2) do |config|
  
  config.vm.define "n1" do |n1|
    n1.vm.box = "ubuntu/xenial64"
    n1.vm.hostname = "n1"
    n1.vm.network "private_network", type: "dhcp"
    n1.vm.box_check_update = false
    n1.vm.provision "shell", path: "install_docker.sh"
    
    config.vm.provider "virtualbox" do |vb|
      vb.memory = "1024"
    end
  end
  
  config.vm.define "n2" do |n2|
    n2.vm.box = "ubuntu/xenial64"
    n2.vm.hostname = "n2"
    n2.vm.network "private_network", type: "dhcp"
    n2.vm.box_check_update = false
    n2.vm.provision "shell", path: "install_docker.sh"

    config.vm.provider "virtualbox" do |vb|
      vb.memory = "1024"
    end
  end

  # The most common configuration options are documented and commented below.
  # For a complete reference, please see the online documentation at
  # https://docs.vagrantup.com.

  # Every Vagrant development environment requires a box. You can search for
  # boxes at https://atlas.hashicorp.com/search.
  # config.vm.box = "base"

  # Disable automatic box update checking. If you disable this, then
  # boxes will only be checked for updates when the user runs
  # `vagrant box outdated`. This is not recommended.
  # config.vm.box_check_update = false

  # Create a forwarded port mapping which allows access to a specific port
  # within the machine from a port on the host machine. In the example below,
  # accessing "localhost:8080" will access port 80 on the guest machine.
  # config.vm.network "forwarded_port", guest: 80, host: 8080

  # Create a private network, which allows host-only access to the machine
  # using a specific IP.
  # config.vm.network "private_network", ip: "192.168.33.10"

  # Create a public network, which generally matched to bridged network.
  # Bridged networks make the machine appear as another physical device on
  # your network.
  # config.vm.network "public_network"

  # Share an additional folder to the guest VM. The first argument is
  # the path on the host to the actual folder. The second argument is
  # the path on the guest to mount the folder. And the optional third
  # argument is a set of non-required options.
  # config.vm.synced_folder "../data", "/vagrant_data"

  # Provider-specific configuration so you can fine-tune various
  # backing providers for Vagrant. These expose provider-specific options.
  # Example for VirtualBox:
  #
  #   # Display the VirtualBox GUI when booting the machine
  #   vb.gui = true
  #
  #   # Customize the amount of memory on the VM:
  #   vb.memory = "1024"
  # end
  #
  # View the documentation for the provider you are using for more
  # information on available options.

  # Define a Vagrant Push strategy for pushing to Atlas. Other push strategies
  # such as FTP and Heroku are also available. See the documentation at
  # https://docs.vagrantup.com/v2/push/atlas.html for more information.
  # config.push.define "atlas" do |push|
  #   push.app = "YOUR_ATLAS_USERNAME/YOUR_APPLICATION_NAME"
  # end

  # Enable provisioning with a shell script. Additional provisioners such as
  # Puppet, Chef, Ansible, Salt, and Docker are also available. Please see the
  # documentation for more information about their specific syntax and use.
  # config.vm.provision "shell", inline: <<-SHELL
  #   sudo apt-get update
  #   sudo apt-get install -y apache2
  # SHELL
end