Enhanced variable handling

- Load variables from .vagrant_settings
- Provide default values

.gitignore

@@ -1,2 +1,3 @@
 .vagrant
+.vagrant_settings
 .vscode

Vagrantfile

@@ -1,12 +1,34 @@
+# -*- mode: ruby -*-
+# vi: set ft=ruby :
+
+# Load overrides
+require 'yaml'
+settings_path = '.vagrant_settings'
+settings = {}
+
+if File.exist?(settings_path)
+  settings = YAML.load_file(settings_path)
+end
+
+VAGRANT_CPUS         = settings["VAGRANT_CPUS"]         || 2
+VAGRANT_MEMORY       = settings["VAGRANT_MEMORY"]       || 4096
+VAGRANT_NETWORK_NAME = settings["VAGRANT_NETWORK_NAME"] || "vagrant-libvirt"
+VAGRANT_NETWORK_ADDR = settings["VAGRANT_NETWORK_ADDR"] || "192.168.121.0/24"
+
+# Vagrant
 Vagrant.configure("2") do |config|
   config.vm.box = "debian/bookworm64"
   config.vm.network "private_network", type: "dhcp"
   config.vm.synced_folder ".", "/vagrant", disabled: true
 
-  # Libvrit settings
-  config.vm.provider :libvirt do |domain|
-    domain.memory = 4096
-    domain.cpus = 2
+  # Libvirt settings
+  config.vm.provider :libvirt do |libvirt|
+    libvirt.cpu_mode = "host-model"
+    libvirt.cpus = VAGRANT_CPUS
+    libvirt.memory = VAGRANT_MEMORY
+    libvirt.management_network_name = VAGRANT_NETWORK_NAME
+    libvirt.management_network_address = VAGRANT_NETWORK_ADDR
+    libvirt.nested = true
   end
 
   # Boot with a GUI in VirtualBox
@@ -14,8 +36,8 @@ Vagrant.configure("2") do |config|
     vbox.customize ["modifyvm", :id, "--vram", "128",
                     "--graphicscontroller", "vboxvga",
                     "--accelerate3d", "on"]
-    vbox.memory = 4096
-    vbox.cpus = 2
+    vbox.memory = VAGRANT_MEMORY
+    vbox.cpus = VAGRANT_CPUS
     vbox.gui = true
   end