Merge pull request #442 from infernix/box_optional

Make boxes optional and move boot ordering into a separate class

README.md

@@ -22,6 +22,7 @@ welcome and can help a lot :-)
 * Snapshots via [sahara](https://github.com/jedi4ever/sahara).
 * Package caching via [vagrant-cachier](http://fgrehm.viewdocs.io/vagrant-cachier/).
 * Use boxes from other Vagrant providers via [vagrant-mutate](https://github.com/sciurus/vagrant-mutate).
+* Support VMs with no box for PXE boot purposes (Vagrant 1.6 and up)
 
 ## Future work
 
@@ -172,7 +173,7 @@ end
 * `machine` - Sets machine type. Equivalent to qemu `-machine`. Use `qemu-system-x86_64 -machine help` to get a list of supported machines.
 * `machine_arch` - Sets machine architecture. This helps libvirt to determine the correct emulator type. Possible values depend on your version of qemu. For possible values, see which emulator executable `qemu-system-*` your system provides. Common examples are `aarch64`, `alpha`, `arm`, `cris`, `i386`, `lm32`, `m68k`, `microblaze`, `microblazeel`, `mips`, `mips64`, `mips64el`, `mipsel`, `moxie`, `or32`, `ppc`, `ppc64`, `ppcemb`, `s390x`, `sh4`, `sh4eb`, `sparc`, `sparc64`, `tricore`, `unicore32`, `x86_64`, `xtensa`, `xtensaeb`.
 * `machine_virtual_size` - Sets the disk size in GB for the machine overriding the default specified in the box. Allows boxes to defined with a minimal size disk by default and to be grown to a larger size at creation time. Will ignore sizes smaller than the size specified by the box metadata. Note that currently there is no support for automatically resizing the filesystem to take advantage of the larger disk.
-* `boot` - Change the boot order and enables the boot menu. Possible options are "hd" or "network". Defaults to "hd" with boot menu disabled. When "network" is set first, *all* NICs will be tried before the first disk is tried.
+* `boot` - Change the boot order and enables the boot menu. Possible options are "hd", "network", "cdrom". Defaults to "hd" with boot menu disabled. When "network" is set without "hd", only all NICs will be tried; see below for more detail.
 * `nic_adapter_count` - Defaults to '8'. Only use case for increasing this count is for VMs that virtualize switches such as Cumulus Linux. Max value for Cumulus Linux VMs is 33.
 
 
@@ -197,7 +198,8 @@ Vagrant.configure("2") do |config|
 
 The following example shows part of a Vagrantfile that enables the VM to
 boot from a network interface first and a hard disk second. This could be
-used to run VMs that are meant to be a PXE booted machines.
+used to run VMs that are meant to be a PXE booted machines. Be aware that 
+if `hd` is not specified as a boot option, it will never be tried.
 
 ```ruby
 Vagrant.configure("2") do |config|
@@ -425,6 +427,38 @@ Vagrant.configure("2") do |config|
 end
 ```
 
+## No box and PXE boot
+
+There is support for PXE booting VMs with no disks as well as PXE booting VMs with blank disks. There are some limitations:
+
+* Requires Vagrant 1.6.0 or newer
+* No provisioning scripts are ran
+* No network configuration is being applied to the VM
+* No SSH connection can be made
+* ```vagrant halt``` will only work cleanly if the VM handles ACPI shutdown signals 
+
+In short, VMs without a box can be created, halted and destroyed but all other functionality cannot be used.
+
+An example for a PXE booted VM with no disks whatsoever:
+
+Vagrant.configure("2") do |config|
+  config.vm.define :pxeclient do |pxeclient|
+    pxeclient.vm.provider :libvirt do |domain|
+      domain.boot 'network'
+    end
+  end
+
+And an example for a PXE booted VM with no box but a blank disk which will boot from this HD if the NICs fail to PXE boot::
+
+Vagrant.configure("2") do |config|
+  config.vm.define :pxeclient do |pxeclient|
+    pxeclient.vm.provider :libvirt do |domain|
+      domain.storage :file, :size => '100G', :type => 'qcow2'
+      domain.boot 'network'
+      domain.boot 'hd'
+    end
+  end
+
 ## SSH Access To VM
 
 vagrant-libvirt supports vagrant's [standard ssh settings](https://docs.vagrantup.com/v2/vagrantfile/ssh_settings.html).

lib/vagrant-libvirt/action.rb

@@ -23,6 +23,13 @@ module VagrantPlugins
             # Create VM if not yet created.
             if !env[:result]
               b2.use SetNameOfDomain
+              if !env[:machine].box
+                b2.use CreateDomain
+                b2.use CreateNetworks
+                b2.use CreateNetworkInterfaces
+                b2.use SetBootOrder
+                b2.use StartDomain
+              else
                 b2.use HandleStoragePool
                 b2.use HandleBox
                 b2.use HandleBoxImage
@@ -37,6 +44,7 @@ module VagrantPlugins
                 b2.use ShareFolders
                 b2.use CreateNetworks
                 b2.use CreateNetworkInterfaces
+                b2.use SetBootOrder
 
                 b2.use StartDomain
                 b2.use WaitTillUp
@@ -44,6 +52,7 @@ module VagrantPlugins
                 b2.use ForwardPorts
                 b2.use SetHostname
                 # b2.use SyncFolders
+              end
             else
               b2.use action_start
             end
@@ -68,12 +77,19 @@ module VagrantPlugins
                 next
               end
 
+              if !env[:machine].box
+                # With no box, we just care about network creation and starting it
+                b3.use CreateNetworks
+                b3.use SetBootOrder
+                b3.use StartDomain
+              else
                 # VM is not running or suspended.
 
                 b3.use Provision
 
                 # Ensure networks are created and active
                 b3.use CreateNetworks
+                b3.use SetBootOrder
 
                 b3.use PrepareNFSValidIds
                 b3.use SyncedFolderCleanup
@@ -93,6 +109,7 @@ module VagrantPlugins
             end
           end
         end
+      end
 
       # This is the action that is primarily responsible for halting the
       # virtual machine.
@@ -154,7 +171,9 @@ module VagrantPlugins
             if !env[:result]
               # Try to remove stale volumes anyway
               b2.use SetNameOfDomain
+              if env[:machine].box
                 b2.use RemoveStaleVolume
+              end
               if !env[:result]
                 b2.use MessageNotCreated
               end
@@ -321,6 +340,7 @@ module VagrantPlugins
       autoload :ReadMacAddresses, action_root.join('read_mac_addresses')
       autoload :ResumeDomain, action_root.join('resume_domain')
       autoload :SetNameOfDomain, action_root.join('set_name_of_domain')
+      autoload :SetBootOrder, action_root.join('set_boot_order')
 
       # I don't think we need it anymore
       autoload :ShareFolders, action_root.join('share_folders')

lib/vagrant-libvirt/action/create_domain.rb

@@ -72,18 +72,29 @@ module VagrantPlugins
 
           @os_type = 'hvm'
 
-          # Get path to domain image from the storage pool selected.
+          # Get path to domain image from the storage pool selected if we have a box.
+          if env[:machine].box
             actual_volumes = 
               env[:machine].provider.driver.connection.volumes.all.select do |x|
                 x.pool_name == @storage_pool_name
               end
             domain_volume = ProviderLibvirt::Util::Collection.find_matching(
-            actual_volumes, "#{@name}.img")
+              actual_volumes,"#{@name}.img")
             raise Errors::DomainVolumeExists if domain_volume.nil?
             @domain_volume_path = domain_volume.path
+          end
 
+          # If we have a box, take the path from the domain volume and set our storage_prefix.
+          # If not, we dump the storage pool xml to get its defined path.
           # the default storage prefix is typically: /var/lib/libvirt/images/
+          if env[:machine].box
             storage_prefix = File.dirname(@domain_volume_path) + '/'        # steal
+          else
+            storage_pool = env[:machine].provider.driver.connection.client.lookup_storage_pool_by_name(@storage_pool_name)
+            raise Errors::NoStoragePool if storage_pool.nil?
+            xml = Nokogiri::XML(storage_pool.xml_desc)
+            storage_prefix = xml.xpath("/pool/target/path").inner_text.to_s + '/'
+          end
 
           @disks.each do |disk|
             disk[:path] ||= _disk_name(@name, disk)
@@ -125,7 +136,9 @@ module VagrantPlugins
           env[:ui].info(" -- Cpus:              #{@cpus}")
           env[:ui].info(" -- Memory:            #{@memory_size / 1024}M")
           env[:ui].info(" -- Loader:            #{@loader}")
+          if env[:machine].box
             env[:ui].info(" -- Base box:          #{env[:machine].box.name}")
+          end
           env[:ui].info(" -- Storage pool:      #{@storage_pool_name}")
           env[:ui].info(" -- Image:             #{@domain_volume_path} (#{env[:box_virtual_size]}G)")
           env[:ui].info(" -- Volume Cache:      #{@domain_volume_cache}")

lib/vagrant-libvirt/action/create_network_interfaces.rb

@@ -20,7 +20,6 @@ module VagrantPlugins
 	        config = env[:machine].provider_config
 	        @nic_model_type = config.nic_model_type
           @nic_adapter_count = config.nic_adapter_count
-          @boot_order = config.boot_order
           @app = app
         end
 
@@ -126,6 +125,8 @@ module VagrantPlugins
           # Continue the middleware chain.
           @app.call(env)
 
+
+          if env[:machine].box
             # Configure interfaces that user requested. Machine should be up and
             # running now.
             networks_to_configure = []
@@ -164,6 +165,7 @@ module VagrantPlugins
             env[:machine].guest.capability(
               :configure_networks, networks_to_configure)
           end
+        end
 
         private
 

lib/vagrant-libvirt/action/set_boot_order.rb

@@ -0,0 +1,66 @@
+require "log4r"
+require 'nokogiri'
+
+module VagrantPlugins
+  module ProviderLibvirt
+    module Action
+      class SetBootOrder
+        def initialize(app, env)
+          @app    = app
+          @logger = Log4r::Logger.new("vagrant_libvirt::action::set_boot_order")
+          config = env[:machine].provider_config
+          @boot_order = config.boot_order
+        end
+
+        def call(env)
+         # Get domain first
+          begin
+            domain = env[:machine].provider.driver.connection.client.lookup_domain_by_uuid(
+              env[:machine].id.to_s)
+          rescue => e
+            raise Errors::NoDomainError,
+              :error_message => e.message
+          end
+
+          # Only execute specific boot ordering if this is defined in the Vagrant file
+          if @boot_order.count >= 1
+          
+            # If a domain is initially defined with no box or disk or with an explicit boot order, libvirt adds <boot dev="foo">
+            # This conflicts with an explicit boot_order configuration, so we need to remove it from the domain xml and feed it back.
+            # Also see https://bugzilla.redhat.com/show_bug.cgi?id=1248514 as to why we have to do this after all devices have been defined.
+            xml = Nokogiri::XML(domain.xml_desc)
+            xml.search("/domain/os/boot").each do |node|
+              node.remove
+            end
+
+            # Parse the XML and find each defined drive and network interfacee
+            hd = xml.search("/domain/devices/disk[@device='disk']")
+            cdrom = xml.search("/domain/devices/disk[@device='cdrom']")
+            network = xml.search("/domain/devices/interface[@type='network']")
+
+            # Generate an array per device group and a flattened array from all of those
+            devices = {"hd" => hd, "cdrom" => cdrom, "network" => network}
+            final_boot_order = @boot_order.flat_map {|category| devices[category] }
+
+            # Loop over the entire defined boot order array and create boot order entries in the domain XML
+            final_boot_order.each_with_index do |node, index|
+              boot = "<boot order='#{index+1}'/>"
+              node.add_child(boot)
+              if node.name == 'disk'
+                @logger.debug "Setting #{node['device']} to boot index #{index+1}"
+              elsif node.name == 'interface'
+                @logger.debug "Setting #{node.name} to boot index #{index+1}"
+              end
+            end
+
+            # Finally redefine the domain XML through libvirt to apply the boot ordering
+            env[:machine].provider.driver.connection.client.define_domain_xml(xml.to_s)
+          end
+
+          @app.call(env)
+
+        end
+      end
+    end
+  end
+end

lib/vagrant-libvirt/plugin.rb

@@ -23,7 +23,7 @@ module VagrantPlugins
         Config
       end
 
-      provider('libvirt', parallel: true) do
+      provider('libvirt', parallel: true, box_optional: true) do
         require_relative 'provider'
         Provider
       end

lib/vagrant-libvirt/templates/domain.xml.erb

@@ -44,17 +44,14 @@
   </features>
   <clock offset='utc'/>
   <devices>
+    <% if @domain_volume_path %>
     <disk type='file' device='disk'>
       <driver name='qemu' type='qcow2' cache='<%= @domain_volume_cache %>'/>
       <source file='<%= @domain_volume_path %>'/>
       <%# we need to ensure a unique target dev -%>
       <target dev='vda' bus='<%= @disk_bus %>'/>
-      <% if @boot_order[0] == 'hd' %>
-        <boot order='1'/>
-      <% elsif @boot_order.count >= 1 %> 
-        <boot order='9'/>
-      <% end %>
     </disk>
+    <% end %>
 <%# additional disks -%>
 <% @disks.each do |d| -%>
     <disk type='file' device='disk'>

lib/vagrant-libvirt/templates/interface.xml.erb

@@ -6,10 +6,5 @@
   <target dev='vnet<%= @iface_number %>'/>
   <alias name='net<%= @iface_number %>'/>
   <model type='<%=@model_type%>'/>
-  <% if @boot_order[0] == 'network' %>
-    <boot order='<%= @iface_number+1 %>'/>
-  <% elsif @boot_order.include?('network') %> 
-    <boot order='<%= @iface_number+2 %>'/>
-  <% end %>
 </interface>