Add support for a nat-less libvirt deployment and multiple workers (#65)

## Description

Allows for deploying the vagrant/libvirt setup without NAT and with multiple workers, which enables testing with cluster-api-provider-tink

## Why is this needed

Helps with testing CAPT

## How Has This Been Tested?

Currently testing at the moment, but all testing will consist of manual testing with vagrant/libvirt

## How are existing users impacted? What migration steps/scripts do we need?

This could affect existing vagrant/libvirt users if they have an existing worker running when they update, not sure if there is a good way to avoid that, though.


## Checklist:

I have:

- [ ] updated the documentation and/or roadmap (if required)
- [ ] added unit or e2e tests
- [ ] provided instructions on how to upgrade

deploy/vagrant/Vagrantfile

@@ -1,5 +1,7 @@
 ENV['VAGRANT_NO_PARALLEL'] = 'yes'
 
+num_workers = ENV['TINKERBELL_NUM_WORKERS'] || '1'
+
 # Returns true if `GUI` environment variable exists, value does not matter.
 # Defaults to false
 def worker_gui_enabled?
@@ -12,6 +14,14 @@ def worker_display_scale_enabled?
   ENV.include?('VAGRANT_WORKER_SCALE')
 end
 
+def configure_nat
+  return ENV.has_key?('TINKERBELL_CONFIGURE_NAT') ? ENV['TINKERBELL_CONFIGURE_NAT'] : 'true'
+end
+
+def libvirt_forward_mode
+  return configure_nat == 'false' ? 'nat' : 'none'
+end
+
 Vagrant.configure('2') do |config|
 
   config.vm.define :provisioner do |provisioner|
@@ -19,7 +29,11 @@ Vagrant.configure('2') do |config|
     provisioner.vm.box_version = "0.1.0"
     provisioner.vm.hostname = 'provisioner'
     provisioner.vm.synced_folder './../../', '/vagrant'
-    provisioner.vm.provision :shell, path: './scripts/tinkerbell.sh'
+    provisioner.vm.provision :shell,
+                        path: './scripts/tinkerbell.sh',
+                        env: {
+                          'TINKERBELL_CONFIGURE_NAT': configure_nat,
+                        }
 
     provisioner.vm.network :private_network,
                         virtualbox__intnet: "tink_network",
@@ -27,7 +41,7 @@ Vagrant.configure('2') do |config|
                         libvirt__host_ip: "192.168.1.6",
                         libvirt__netmask: "255.255.255.248",
                         libvirt__dhcp_enabled: false,
-                        libvirt__forward_mode: 'none',
+                        libvirt__forward_mode: libvirt_forward_mode,
                         libvirt__adapter: 1,
                         auto_config: false
 
@@ -47,14 +61,19 @@ Vagrant.configure('2') do |config|
     end
   end
 
-  config.vm.define "worker" do |worker|
+
+  (1..num_workers.to_i).each do |i|
+    mac_suffix = "%02x" % i
+    worker_suffix = i==1 ? "" : "i"
+    config.vm.define "worker#{worker_suffix}" do |worker|
+      
       worker.vm.box = nil
       worker.vm.network :private_network,
-                      mac: "080027000001",
+                        mac: "0800270000#{mac_suffix}",
                         virtualbox__intnet: "tink_network",
                         libvirt__network_name: "tink_network",
                         libvirt__dhcp_enabled: false,
-                      libvirt__forward_mode: 'none',
+                        libvirt__forward_mode: libvirt_forward_mode,
                         auto_config: false
 
       worker.vm.provider :libvirt do |lv|
@@ -82,8 +101,9 @@ Vagrant.configure('2') do |config|
           '--boot2', 'none',
           '--boot3', 'none',
           '--boot4', 'none',
-        '--macaddress1', '080027000001'
+          '--macaddress1', "0800270000#{mac_suffix}"
         ]
       end
     end
   end
+end

deploy/vagrant/scripts/tinkerbell.sh

@@ -45,10 +45,12 @@ main() (
 
 	./setup.sh
 
+	if [[ ${TINKERBELL_CONFIGURE_NAT:=true} != "false" ]]; then
 		setup_nat
+	fi
+
 	secure_certs
 	configure_vagrant_user
-
 )
 
 main