This might sound like a pretty simple and basic question, right? However, the answer will actually depend on what you are trying to do. The motivation for this blog post actually stemmed from a conversation I had with one of our Engineers who works over in our core Platform Management Infrastructure which includes VMware Tools, Guest OS Customization, Guest Operations, etc. Although I was aware of some of these methods in determining when a VM was ready, I came to learn about a few new other methods that I was not aware of before. This is really one of the things I love about my job, constantly learning new things and diving deeper into our technologies and sharing that back with our customers to help enable them and their business.
So, what does it even mean for a Virtual Machine to be "ready"? Is it when the VM is powered on? Is it when the VM obtains an IP Address? Is it when the GuestOS is fully customized or is it when I can SSH or RDP to the system? Depending on what you are trying to accomplish, the answer will vary. In addition to that, there are two distinct VM states to consider. The first being the actual Virtual Machine state and the second being the GuestOS state.
Virtual Machine State
The VM state is pretty straight forward, it describes the "Hard" power state of the VM which can either be powered on, powered off or suspended. As you can probably guess, you will need to make sure the VM is powered on before you attempt to check whether the GuestOS is ready 🙂
Using the vSphere API, you can find the VM powerState under:
VirtualMachine->Runtime->powerState
Here is a PowerCLI snippet using the out of box cmdlet to get the power state for a VM named "air":
Get-VM -Name air | Select PowerState
Here is a PowerCLI snippet that uses the vSphere API via Get-View to retrieve the exact same information:
$vm = Get-View -ViewType Virtualmachine -Property Name,Runtime -Filter @{"name"="air"}
$vm.Runtime.PowerState
