Merge pull request #5884 from dcbw/dcbw/fedora-network-mac-address

[fedora] honor MAC address when configuring networks

plugins/guests/fedora/cap/configure_networks.rb

@@ -16,6 +16,7 @@ module VagrantPlugins
 
           virtual = false
           interface_names = Array.new
+          interface_names_by_slot = Array.new
           machine.communicate.sudo("/usr/sbin/biosdevname; echo $?") do |_, result|
             virtual = true if ['4', '127'].include? result.chomp
           end
@@ -25,7 +26,7 @@ module VagrantPlugins
               interface_names = result.split("\n")
             end
 
-            interface_names = networks.map do |network|
+            interface_names_by_slot = networks.map do |network|
                "#{interface_names[network[:interface]]}"
             end
           else
@@ -44,18 +45,39 @@ module VagrantPlugins
                "eth#{network[:interface]}"
             end
 
+            interface_names_by_slot = interface_names.dup
             interface_name_pairs.each do |interface_name, previous_interface_name|
               if setting_interface_names.index(previous_interface_name) == nil
-                interface_names.delete(interface_name)
+                interface_names_by_slot.delete(interface_name)
               end
             end
           end
 
+          # Read interface MAC addresses for later matching
+          mac_addresses = Array.new(interface_names.length)
+          interface_names.each_with_index do |ifname, index|
+            machine.communicate.sudo("cat /sys/class/net/#{ifname}/address") do |_, result|
+              mac_addresses[index] = result.strip
+            end
+          end
+
           # Accumulate the configurations to add to the interfaces file as well
           # as what interfaces we're actually configuring since we use that later.
           interfaces = Set.new
           networks.each do |network|
-            interface = interface_names[network[:interface]-1]
+            interface = nil
+            if network[:mac_address]
+              found_idx = mac_addresses.find_index(network[:mac_address])
+              # Ignore network if requested MAC address could not be found
+              next if found_idx.nil?
+              interface = interface_names[found_idx]
+            else
+              ifname_by_slot = interface_names_by_slot[network[:interface]-1]
+              # Don't overwrite if interface was already matched via MAC address
+              next if interfaces.include?(ifname_by_slot)
+              interface = ifname_by_slot
+            end
+
             interfaces.add(interface)
             network[:device] = interface