Automatic Virtual Machine Activation was a feature that was added in Windows Server 2012 R2 that enables the activation of your VMs without using a KMS server or MAK key without the requirement of  internet connectivity.  As you create new VMs they activate against the host Hyper-v server. This method of activation only lasts 7 days before the VM renews it’s activation.  Ideal for Datacenter hosts as you can also report on this too.
AVMA requires the Hyper-v host to be running Server 2012 R2 or 2016 Datacenter and it must be activated.   The VMs that run on the host must be at least 2012 R2 or above to activate.  VM’s that can be activated using this method include 2012 R2/2016 Datacenter, Standard and Essentials.
When installing / entering a product key for the the guest VMs, you must enter the AVMA product key displayed below:
Windows Server 2012 R2
EditionAVMA key
DatacenterY4TGP-NPTV9-HTC2H-7MGQ3-DV4TW
StandardDBGBW-NPF86-BJVTX-K3WKJ-MTB6V
EssentialsK2XGM-NMBT3-2R6Q8-WF2FK-P36R2

Windows Server 2016
EditionAVMA key
DatacenterTMJ3Y-NTRTM-FJYXT-T22BY-CWG3J
StandardC3RCX-M6NRP-6CXC9-TW2F2-4RHYD
EssentialsB4YNW-62DX9-W8V6M-82649-MHBKQ

In order for the VM’s to talk to the host for activation, the Data Exchange option needs to be activated on the Integration Services.  To ensure this is enabled click on the Settings of the VM and ensure the option is selected:
image
If you need to changed the product key of a VM to activate it using AVMA then open a command prompt as an Administrator and enter the following command:
slmgr –ipk
e.g.
slmgr –ipk C3RCX-M6NRP-6CXC9-TW2F2-4RHYD
How easy is that?