Windows Activation
There are two main scenarios for Volume Activation of Windows:
- Multiple Activation Key (MAK)
- Key Management Service (KMS)
MAK
MAK keys activate individual Windows installations on each machine. Each MAK key has a predetermined number of activations associated with it. Once all activations are used up, the key must be re-purchased or extended.
You can centralize the management of MAK and KMS keys with Volume Activation Management Tool (VAMT), VAMT is distributed as part of the Windows Assessment and Deployment Kit (Windows ADK).
When a computer in Host Provisioning receives a vDisk update or the option to wipe-out the disk when rebooted is enabled, the system may need to be re-activated. Host Provisioning Client automates this when you set a Windows Key in the Computer Group, as many computers can be updated many times, you may run out of activations very soon.
You can set a Windows MAK Key in the Computer Groups configuration.
KMS
In a KMS setup, a KMS host server is set up on the network. This server activates Windows clients using a KMS key.
This is the recommended aproach in virtualization systems, as there is no activation limits associated with a KMS Key, the same computer can be re-activated unlimited times. We highly recommend using KMS on Host Provisioning Services.
In KMS you set a public key (GVLK Key) to Windows Clients depending on the Windows Edition you are running, the KMS client is activated for 180 days and tries to renew the activation every 7 days. If the KMS client is unable to contact the KMS license server for 180 days, a 30 days grace period is granted. After the 30-day grace period expires, Windows will switch to Reduced Functionality Mode (RFM). You can get the public GVLK Keys in Microsoft's website.
You can set a public Windows GVLK/KMS Key for clients in the Computer Groups configuration.
KMS server can activate clients in different domains and workgroups. During the installation of a KMS server, you can automatically register a SRV record in the domain's DNS, any client can find the name of the KMS server in the domain using this DNS record. Learn more about planning your KMS infraestructure.
A KMS Host Key (CSVLK key) can be obtained by any Microsoft corporate customer in their personal account on the Microsoft Volume Licensing (VLSC) site, but currently is not listed by default. Microsoft will generate a KMS host key for you if you contact technical support. Learn more about Windows Product Keys.