[packer] Handle VBox versions requiring --nat-localhostreachableN

packer/packer-template.json

@@ -12,10 +12,11 @@
     "cmd_ansible" : "/tmp/ansible_venv/bin/ansible-playbook",
     "memory"      : "2048",
     "disk_size"   : "65536",
-    "off_cmd"     : "poweroff"
+    "off_cmd"     : "poweroff",
+    "nat_key"     : "{{env `ARCH_ANSIBLE_PACKER_VBOX_NAT_LOCALHOST_KEY`}}",
+    "nat_val"     : "{{env `ARCH_ANSIBLE_PACKER_VBOX_NAT_LOCALHOST_VAL`}}"
   },
 
-
   "builders": [
     {
       "name" : "virtualbox-uefi",
@@ -38,6 +39,7 @@
       "iso_interface" : "sata",
       "vboxmanage": [
         ["modifyvm", "{{.Name}}", "--nictype1", "virtio"],
+        ["modifyvm", "{{.Name}}", "{{user `nat_key`}}", "{{user `nat_val`}}"],
         ["modifyvm", "{{.Name}}", "--vram", "16"],
         ["modifyvm", "{{.Name}}", "--rtcuseutc", "on"],
         ["modifyvm", "{{.Name}}", "--graphicscontroller", "vmsvga"],
@@ -65,6 +67,7 @@
       "iso_interface" : "sata",
       "vboxmanage": [
         ["modifyvm", "{{.Name}}", "--nictype1", "virtio"],
+        ["modifyvm", "{{.Name}}", "{{user `nat_key`}}", "{{user `nat_val`}}"],
         ["modifyvm", "{{.Name}}", "--vram", "16"],
         ["modifyvm", "{{.Name}}", "--rtcuseutc", "on"],
         ["modifyvm", "{{.Name}}", "--graphicscontroller", "vmsvga"],

packer/packer-wrapper.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+
+set -ex
+
+if VBoxManage modifyvm --help 2>&1 | grep -q -- --nat-localhostreachableN; then
+  export ARCH_ANSIBLE_PACKER_VBOX_NAT_LOCALHOST_KEY="--nat-localhostreachable1"
+  export ARCH_ANSIBLE_PACKER_VBOX_NAT_LOCALHOST_VAL="on"
+else
+  # Since the JSON is static, we must pass something valid into these vars
+  # but it also has to be idempotent. Just restate that the first NIC is NAT.
+  export ARCH_ANSIBLE_PACKER_VBOX_NAT_LOCALHOST_KEY="--nic1"
+  export ARCH_ANSIBLE_PACKER_VBOX_NAT_LOCALHOST_VAL="nat"
+fi
+
+packer "$@"