Vagrant for multiple machines

chef.json

{
"chef": {
":chef_server_url": "https://api.opscode.com/organizations/my-organization",
":client_key_path": "/etc/chef/my-client.pem",
":environment": "my-environment",
":provisioning_path": "/etc/chef",
":validation_client_name": "my-client",
":validation_key_path": "~/.chef/my-client.pem"
}
}

nodes.json

{
  "nodes": {
    "apps": {
      ":node": "ApplicationServer-201",
      ":ip": "192.168.33.21",
      ":host": "apps.server-201",
      "ports": [
        {
          ":host": 2201,
          ":guest": 22,
          ":id": "ssh"
        },
        {
          ":host": 7709,
          ":guest": 7709,
          ":id": "wls-listen"
        }
      ],
      ":memory": 2048
    },
    "dbs": {
      ":node": "DatabaseServer-301",
      ":ip": "192.168.33.31",
      ":host": "dbs.server-301",
      "ports": [
        {
          ":host": 2202,
          ":guest": 22,
          ":id": "ssh"
        },
        {
          ":host": 1529,
          ":guest": 1529,
          ":id": "xe-db"
        },
        {
          ":host": 8380,
          ":guest": 8380,
          ":id": "xe-listen"
        }
      ],
      ":memory": 2048
    },
    "web": {
      ":node": "WebServer-401",
      ":ip": "192.168.33.41",
      ":host": "web.server-401",
      "ports": [
        {
          ":host": 2203,
          ":guest": 22,
          ":id": "ssh"
        },
        {
          ":host": 4756,
          ":guest": 4756,
          ":id": "apache"
        }
      ],
      ":memory": 1024
    }
  }
}

Vagrantfile.rb

# -*- mode: ruby -*-
# vi: set ft=ruby :
 
# Multi-VM Configuration: Builds Web, Application, and Database Servers using JSON config file
# Configures VMs based on Hosted Chef Server defined Environment and Node (vs. Roles)
# Author: Gary A. Stafford
 
# read vm and chef configurations from JSON files
nodes_config = (JSON.parse(File.read("nodes.json")))['nodes']
chef_config = (JSON.parse(File.read("chef.json")))['chef']
 
VAGRANTFILE_API_VERSION = "2"
 
Vagrant.require_plugin "vagrant-omnibus"
 
Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
config.vm.box = "vagrant-oracle-vm-saucy64"
config.vm.box_url = "http://cloud-images.ubuntu.com/vagrant/saucy/current/saucy-server-cloudimg-amd64-vagrant-disk1.box"
 
config.omnibus.chef_version = :latest
 
nodes_config.each do |node|
node_name = node[0] # name of node
node_values = node[1] # content of node
 
config.vm.define node_name do |config|
# configures all forwarding ports in JSON array
ports = node_values['ports']
ports.each do |port|
config.vm.network :forwarded_port,
host: port[':host'],
guest: port[':guest'],
id: port[':id']
end
 
config.vm.hostname = node_values[':node']
config.vm.network :private_network, ip: node_values[':ip']
 
# syncs local repository of large third-party installer files (quicker than downloading each time)
config.vm.synced_folder "#{ENV['HOME']}/Documents/git_repos/chef-artifacts", "/vagrant"
 
config.vm.provider :virtualbox do |vb|
vb.customize ["modifyvm", :id, "--memory", node_values[':memory']]
vb.customize ["modifyvm", :id, "--name", node_values[':node']]
end
 
# chef configuration section
config.vm.provision :chef_client do |chef|
chef.environment = chef_config[':environment']
chef.provisioning_path = chef_config[':provisioning_path']
chef.chef_server_url = chef_config[':chef_server_url']
chef.validation_key_path = chef_config[':validation_key_path']
chef.node_name = node_values[':node']
chef.validation_client_name = chef_config[':validation_client_name']
chef.client_key_path = chef_config[':client_key_path']
end
end
end
end

Quoting from

http://programmaticponderings.wordpress.com/2014/02/27/multi-vm-creation-using-vagrant-and-json/#comment-13152