Wednesday, March 10, 2010

KMS requirements

Microsoft Volume Licensing Activation comes in 2 forms: Multiple Activation Key (MAK) and Key Management Service (KMS). It is also well published in Microsoft website if you have at least 5 servers or 25 clients, you should go for KMS.

Now, we have about a dozen of servers in a particular network activated by KMS. Recently, I joined the first Win7 client to the domain and was unable to activate this client. Error: "The count reported by your KMS server is insufficient". Ops! I thought I already have more than 5 servers in this domain!?

A further check with Microsoft now confirms this:
KMS volume activation requires a minimum number of physical Windows clients: five (5) for Windows Server 2008, or twenty five(25) for Windows Vista. However, KMS does not differentiate between the two systems when counting the total number of clients. For example, a KMS host with a count of three (3) Windows Vista clients and two (2) Windows Server 2008 clients would activate the two (2) Windows Server 2008 clients because the cumulative count is five (5) clients. But KMS would not activate the three (3) Windows Vista computers until the total client count reached twenty-five (25). Each time a new machine contacts a KMSHOST, it is added to the count for thirty calendar (30) days, after which its record is deleted, similar to Time-To-Live (TTL) for Domain Name System (DNS) records.

No comments:

Post a Comment