Automating Virtual Machine operations on ESXi Server from C#

VMware provides two really useful API’s for automating virtual machine (VM) tasks on both VMware Workstation and VMware ESXi server.

  • VI Infrastructure API

These are extremely easy to use from C#. In a QA environment, the automation of VM’s can be hugely benifical, wheather attempting to automate an environment for build sanity checks or functional tests.

This post will outline the basics of using the VIX API from C#, in order to perform operations on VMware ESXi server. If you don’t have access to an ESXi server, you can install it on a VM, it’s free to download from the VMware website!

For starters, you will need to install the API’s on your development machine. In order to download, you will need to create a VMware account, which you may already have if you have downloaded Workstation or ESXi server in the past. If you dont, you can create an account for free. Once logged into your account, you can download both API’s from the ‘Support & Downloads’ section.

Let me explain the differance between these two API’s. From VMware’s own documentation:

The VI API provides access to the VMware Infrastructure management components—the managed objects that can be used to manage, monitor, and control life-cycle operations of virtual machines and other VMware infrastructure components (datacenters, datastores, networks, and so on).”

VIX on the other hand, is used to automate the actual operations on VM’s, such as booting them, copying in files, getting/setting VM environment varibles and other tasks you may wish to perform. The coolest part of VIX is that a wrapper for C# exists, created by Daniel Doubrovkine over at This wrapper, ‘VMwareTasks’, provides a simple object-orientated approach to VIX, which will be familar to C# developers. Download the wrapper here.

Now for the basics of using the VIX API and VMwareTasks wrapper. Create a new console application project in Visual Studio. You will need to add a reference to the VMwareTasks DLL, which is located in the ‘bin’ directory when you extract the VMwareTasks download.

Look how simple it is to power on a VM!

// Declare a new virtual host
VMWareVirtualHost host = new VMWareVirtualHost();

// Connect to the ESXi server
host.ConnectToVMWareVIServer("", "root", "password123");

// Power on an existing VM by name
VMWareVirtualMachine machine = host.Open("[datastore1] XPP_SP2.vmx");

The simple code above just connects to an ESXi server, and powers on an existing VM, but you can see how easy it is to perform operations on VM’s.

Here’s how to create and revert to a snapshot:

VMWareVirtualHost host = new VMWareVirtualHost();
host.ConnectToVMWareVIServer("", "root", "password123");
VMWareVirtualMachine machine = host.Open("[datastore1] Vista_EN.vmx");
machine.Login("Tester", "testing");

string snapShotName = "base";
machine.Snapshots.CreateSnapshot(snapShotName, "Clean");

VMWareSnapshot snapshot = machine.Snapshots.GetNamedSnapshot("base");

Or to create a directory:


You can see from the above examples how easy it is to perform operations on VM’s using these API’s. Install the API’s and play around with the functionality, I guarantee you’ll be impressed!