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
end