Fix: pass MAC addresses to vagrant to configure interfaces correctly

vagrant-libvirt-match-interface-by-mac.patch

@@ -0,0 +1,69 @@
+From ee7afab369dc7e80128ff35a2ff11f6eab23d368 Mon Sep 17 00:00:00 2001
+From: Dan Williams <dcbw@redhat.com>
+Date: Tue, 30 Jun 2015 16:24:30 -0500
+Subject: [PATCH] Read MAC address from libvirt and pass up to Vagrant
+
+Configuring networks based solely on slot numbers doesn't work very
+well, since there's no way to guarantee that the interface Vagrant
+finds is the same one that vagrant-libvirt created at that index.
+
+For example, Vagrant's Fedora configure_networks action does this:
+
+  machine.communicate.sudo("ls /sys/class/net | grep -v lo") do |_, result|
+    interface_names = result.split("\n")
+  end
+
+  interface_names = networks.map do |network|
+    "#{interface_names[network[:interface]]}"
+  end
+
+which means that if your image has 'docker' pre-installed, then
+interface_names[0] = "docker0" and hilarity ensues, with the first
+non-management network being assigned to the vagrant-libvirt
+management interface.
+
+Since interface names are very unreliable (they can be renamed by
+udev at will or when hardware changes) the only way to ensure that
+the interface vagrant-libvirt attaches to the domain maps to the
+correct one inside the VM is by MAC address.  Pull the MAC address
+out of the libvirt config once the interface has been attached and
+pass that up to Vagrant so we have a chance of doing the right thing.
+---
+ lib/vagrant-libvirt/action/create_network_interfaces.rb | 17 ++++++++++++++++-
+ 1 file changed, 16 insertions(+), 1 deletion(-)
+
+diff --git a/lib/vagrant-libvirt/action/create_network_interfaces.rb b/lib/vagrant-libvirt/action/create_network_interfaces.rb
+index 35886ad..cbe7562 100644
+--- a/lib/vagrant-libvirt/action/create_network_interfaces.rb
++++ b/lib/vagrant-libvirt/action/create_network_interfaces.rb
+@@ -96,6 +96,21 @@ def call(env)
+               raise Errors::AttachDeviceError,
+                 :error_message => e.message
+             end
++
++            # Re-read the network configuration and grab the MAC address
++            if !@mac
++              xml = Nokogiri::XML(domain.xml_desc)
++              if iface_configuration[:iface_type] == :public_network
++                if @type == 'direct'
++                  @mac = xml.xpath("/domain/devices/interface[source[@dev='#{@device}']]/mac/@address")
++                else
++                  @mac = xml.xpath("/domain/devices/interface[source[@bridge='#{@device}']]/mac/@address")
++                end
++              else
++                @mac = xml.xpath("/domain/devices/interface[source[@network='#{@network_name}']]/mac/@address")
++              end
++              iface_configuration[:mac] = @mac.to_s
++            end
+           end
+ 
+           # Continue the middleware chain.
+@@ -116,7 +131,7 @@ def call(env)
+             network = {
+               :interface                       => slot_number,
+               :use_dhcp_assigned_default_route => options[:use_dhcp_assigned_default_route],
+-              #:mac => ...,
++              :mac_address => options[:mac],
+             }
+ 
+             if options[:ip]

vagrant-libvirt.spec

@@ -2,7 +2,7 @@
 
 Name: %{vagrant_plugin_name}
 Version: 0.0.30
-Release: 2%{?dist}
+Release: 3%{?dist}
 Summary: libvirt provider for Vagrant
 Group: Development/Languages
 License: MIT
@@ -10,6 +10,10 @@ URL: https://github.com/pradels/vagrant-libvirt
 Source0: https://rubygems.org/gems/%{vagrant_plugin_name}-%{version}.gem
 Source1: 10-vagrant-libvirt.rules
 
+# Pass MAC addresses up to vagrant to ensure interfaces are configured correctly
+# https://github.com/pradels/vagrant-libvirt/pull/408
+Patch0: vagrant-libvirt-match-interface-by-mac.patch
+
 Requires(pre): shadow-utils
 Requires(posttrans): vagrant
 Requires(preun): vagrant
@@ -50,6 +54,7 @@ gem unpack %{SOURCE0}
 
 gem spec %{SOURCE0} -l --ruby > %{vagrant_plugin_name}.gemspec
 
+%patch0 -p1
 
 %build
 gem build %{vagrant_plugin_name}.gemspec
@@ -109,6 +114,9 @@ getent group vagrant >/dev/null || groupadd -r vagrant
 
 
 %changelog
+* Fri Jul 10 2015 Dan Williams <dcbw@redhat.com> - 0.0.30-3
+- Fix: pass MAC addresses to vagrant to configure interfaces correctly
+
 * Fri Jun 19 2015 Fedora Release Engineering <rel-eng@lists.fedoraproject.org> - 0.0.30-2
 - Rebuilt for https://fedoraproject.org/wiki/Fedora_23_Mass_Rebuild