Added option for NIC type.

builder/virtualbox/iso/builder.go

@@ -55,6 +55,15 @@ type Config struct {
 	// The size, in megabytes, of the hard disk to create for the VM. By
 	// default, this is 40000 (about 40 GB).
 	DiskSize uint `mapstructure:"disk_size" required:"false"`
+	// The NIC type to be used for the network interfaces.
+	// When set to 82540EM, the NICs are Intel PRO/1000 MT Desktop (82540EM). This is the default.
+	// When set to 82543GC, the NICs are Intel PRO/1000 T Server (82543GC).
+	// When set to 82545EM, the NICs are Intel PRO/1000 MT Server (82545EM).
+	// When set to Am79C970A, the NICs are AMD PCNet-PCI II network card (Am79C970A).
+	// When set to Am79C973, the NICs are AMD PCNet-FAST III network card (Am79C973).
+	// When set to Am79C960, the NICs are AMD PCnet-ISA/NE2100 (Am79C960).
+	// When set to virtio, the NICs are VirtIO.
+	NICType string `mapstructure:"nic_type" required:"false"`
 	// The guest OS type being installed. By default this is other, but you can
 	// get dramatic performance improvements by setting this to the proper
 	// value. To view all available values for this run VBoxManage list
@@ -200,6 +209,17 @@ func (b *Builder) Prepare(raws ...interface{}) ([]string, []string, error) {
 		b.config.HardDriveInterface = "ide"
 	}
 
+	if b.config.NICType == "" {
+		b.config.NICType = "82540EM"
+	}
+	switch b.config.NICType {
+	case "82540EM", "82543GC", "82545EM", "Am79C970A", "Am79C973",  "Am79C960", "virtio":
+		// do nothing
+	default:
+		errs = packersdk.MultiErrorAppend(
+			errs, errors.New("NIC type can only be 82540EM, 82543GC, 82545EM, Am79C970A, Am79C973, Am79C960 or virtio"))
+	}
+
 	if b.config.GuestOSType == "" {
 		b.config.GuestOSType = "Other"
 	}

builder/virtualbox/iso/step_create_vm.go

@@ -26,7 +26,7 @@ func (s *stepCreateVM) Run(ctx context.Context, state multistep.StateBag) multis
 
 	name := config.VMName
 
-	commands := make([][]string, 8)
+	commands := make([][]string, 9)
 	commands[0] = []string{
 		"createvm", "--name", name,
 		"--ostype", config.GuestOSType, "--register",
@@ -47,6 +47,16 @@ func (s *stepCreateVM) Run(ctx context.Context, state multistep.StateBag) multis
 
 	commands[6] = []string{"modifyvm", name, "--chipset", config.Chipset}
 	commands[7] = []string{"modifyvm", name, "--firmware", config.Firmware}
+	// Set the configured NIC type for all 8 possible NICs
+	commands[8] = []string{"modifyvm", name,
+                          "--nictype1", config.NICType,
+                          "--nictype2", config.NICType,
+                          "--nictype3", config.NICType,
+                          "--nictype4", config.NICType,
+                          "--nictype5", config.NICType,
+                          "--nictype6", config.NICType,
+                          "--nictype7", config.NICType,
+                          "--nictype8", config.NICType}
 
 	ui.Say("Creating virtual machine...")
 	for _, command := range commands {