Tag Archives: vsphere

*Note: This is a repost due to moving my posts from SystemsGame.com to 2ninjas1blog.com”

I was surprised recently to find that no builtin workflow existed for changing the backing information for a VM if you aren’t using a VDS. Now, before I go any further, I’m a big fan of moving to a vSphere Distributed Switch mode, but there are certainly cases where you might encounter a standard vSwitch environment which you need to automate port group changes upon.

The Approach:

Essentially when it comes to changing NIC settings on a VM, you have to change the “Backing” information for the NIC associated with the VM. In my case this was for VMs which were just built as part of an overall automation process, and had only one NIC.

Step 1: Create Action Item.

I created an action item which has 2 inputs.

“vm” of type VC:VirtualMachine – This is basically so you can select the VM in vCO that you want to modify

“vSwitchPGName” of type String – This is so you can pass in the string value of the portgroup name for the vSwitch.

Code:

The code I then used is below. I’ve commented it but please let me know if you have any questions.

var spec = new VcVirtualMachineConfigSpec(); // Initialize a Virtual Machine Config Spec first
var myDeviceChange = new Array(); // Create an array to hold all of your changes
var devices = vm.config.hardware.device;

//Find devices that are VMXNET3 or E1000
for (var i in devices)
	{
		if 	(
				(devices[i] instanceof VcVirtualVmxnet3) ||
				(devices[i] instanceof VcVirtualE1000) 
			)
		{
			System.log("The device we are going to modify is: " + devices[i]);
			var nicChangeSpec = new VcVirtualDeviceConfigSpec(); //This is the specification for the Network adapter we are going to change
			nicChangeSpec.operation = VcVirtualDeviceConfigSpecOperation.edit; //Use edit as we are going to be modifying a NIC
			nicChangeSpec.device = new VcVirtualE1000;
			nicChangeSpec.device.key = devices[i].key; 
			System.log("NicChangeSpec key is : " + nicChangeSpec.device.key);

			nicChangeSpec.device.addressType = devices[i].addressType;
			nicChangeSpec.device.macAddress = devices[i].macAddress;

			System.log("Adding backing info" ) ;
			//Add backing information

			nicChangeSpec.device.backing = new VcVirtualEthernetCardNetworkBackingInfo();
			System.log("Backing info for nicChangeSpec is : " + nicChangeSpec.backing);
			nicChangeSpec.device.backing.deviceName = vSwitchPGName; //Change the backing to the portgroup input
			System.log("Backing info for deviceName on nicChangeSpec is : " + nicChangeSpec.device.backing.deviceName);

			//Push change spec to device change variable
			myDeviceChange.push(nicChangeSpec);

		}
	}

spec.deviceChange = myDeviceChange;
System.log("DeviceChange Spec is: " + spec.deviceChange);
return vm.reconfigVM_Task(spec);

Step 2:

I created a simple workflow which calls this action item and then has a vim3WaitTaskEnd so we can be sure the task is completed before moving on to any other workflows. This is useful if you are going to be incorporating this action into a larger process.

Running the workflow gives you this simple presentation.

And that’s basically all there is to it. Select your VM, type in your PortGroup name, and voila!

For a vDS, VMware included a workflow out of the box in vCO so there is no need to create any of the above.

Enjoy!