License related - How to calculate license.

Question

I am in bit trouble about licensing part. I have two server with dual CPU with 40 Cores each. So total cores are 80.

We want to install ESXI on these both host and want to run 4 windows server as a guest VM.

Please let me how many cores license we need to buy as per Microsoft compliance.

In addition for future use If I want to add another Windows server how many core license I need to run new VM.

Answer 1

so, it depends on which licensing model you are on.

for instance, if you are on some subscription licenses it is like what you can find here: https://www.microsoft.com/licensing/docs/view/Windows-Server

specifically: https://wwlpdocumentsearch.blob.core.windows.net/prodv2/Licensing\_guide\_PLT\_Windows\_Server\_2022\_Oct2022.pdf?sv=2020-08-04&se=2123-10-06T07:11:03Z&sr=b&sp=r&sig=b0VfS%2Fges7x3tP1JKVXDSKF6ewqZ3rDbWvVR8rxPmPM%3D

Which states:

Server licensing and feature overview

Windows Server 2022 Datacenter and Windows Server 2022 Standard are licensed under a core-based license

model. For both Datacenter and Standard , the number of core licenses required depends on whether a

customer is licensing based on the physical cores on the server or by virtual machine. The option to license

Windows Server by virtual machine was added in October 2022, and is available to customers with subscription

licenses or licenses with active Software Assurance only.

• When licensing based on the physical cores on the server, the number of core licenses required equals

the number of physical cores on the licensed server, subject to a minimum of 8 core licenses per

physical processor and a minimum of 16 core licenses per server.

• When licensing by virtual machine, the number of core licenses required equals the number of virtual

cores in the virtual operating system environment (i.e., virtual machine), subject to a minimum of 8

core licenses per virtual machine and 16 core licenses per customer.

Core licenses are sold in 2-packs and 16-packs. For complete details and information on licensing, refer to the

Product Terms. To learn more about core licensing see the Introduction to Microsoft Core Licensing licensing

brief.

it all depends on how many cores you hand out to your virtual servers, and if you have subscription licenses with Software Assurance.

If you have licenses with SA, it depends on how many cores you hand out to your virtual servers.

you need to use minimum 8 core lisenses pr VM and a minimum of 16 core licenses total.

you said that you need to license 4 MVs, that means minimum 8cores*4VMs is 32core licenses.

But if your VMs have more than 8 cores, you need to license all the cores.

if your VMs are: vm1(4cores), vm2(10cores),vm3(12cores),vm4(2cores) you would have to license them like this:

vm1(8cores), vm2(10cores, vm3(12cores), vm4(8cores)= 38cores

at some point it might make sense to change to datacenter licensing, but that calculation gets complex when you can license the virtual machines by virtual CPU.

If you are on SPLA Licenses: (https://www.microsoft.com/licensing/spur/productoffering/WindowsServer/all#UseRights) Server Licenses (per core)

1. Customer may use the server software on a Licensed Server, provided it acquires sufficient Server licenses as described below.
2. The number of Licenses required equals the number of Physical Cores on the Licensed Server, subject to a minimum of 8 Licenses per Physical Processor.
3. Standard edition

• Standard edition permits use of the server software in one OSE on the Licensed Server.
• Standard edition permits use of one Running Instance of the server software in the Physical OSE on the Licensed Server (in addition to one Virtual OSE), if the Physical OSE is used solely to host and Manage the Virtual OSE.
• Customer may assign additional Standard edition Licenses to the Licensed Server equal to the number specified in 2 above and run the server software in one additional OSE on the Licensed Server.

1. Datacenter edition permits use of the server software in any number of OSEs on the Licensed Server.

Server Licenses (per processor)

1. Customer may use the server software on a Licensed Server as described in the Product-Specific License Terms, provided it acquires sufficient Licenses as described below.
2. One License is required for each Physical Processor on a Licensed Server.
3. Each License permits use of one Running Instance of the server software in one OSE.

which means you have to license according to the physical cores or processors.

Then it means you would need to license each VM for all the potential cores it might run on.

If the ESXi's are set up with HA and vMotion, that means all the cores in each hypervisor.

If your servers have 80 physical cores pr server, that means you need to license each VM for 160cores.

so that makes it 640cores for standard licenses for 4 VMs.

At some point it makes more sense to buy 160core datacenter licenses. From what I remember the price cutover used to be at about 7 VMs

So first you need to figure out which license plan you're on, and then read the documentation for that plan

hope this is helpfull :D

-Ole

Answer 2

Hi Ole,

what if I have on ESX HA/DRS enabled but VM mobility disabled?

Do I still need to license the servers serving as non-production DR backups in the cluster?

Regards,

Rudolf

Answer 3

Hi Rudolf.

From what I remember the DR rights are pretty much the same between the different license models, but check your specific license type to be sure.

For SPLA licenses these are the DR rights (Commercial Licensing Terms (microsoft.com):

For each Instance of eligible server software licensed in the Per Processor, Per Core (Applications), Per Core (OS), or Per Core (Management) licensing models that Customer runs in a Physical OSE or Virtual OSE on a Licensed Server, Customer may temporarily run a backup Instance in a Physical OSE or Virtual OSE on a Server dedicated to disaster recovery. The license terms for the software and the following limitations apply to Customer’s use of software on a disaster recovery server. Permitted Periods of Use The disaster recovery server can run only during the following exception periods:

• For brief periods of disaster recovery testing within one week every 90 days.
• During a disaster, while the production server being recovered is down.
• Around the time of a disaster, for a brief period, to assist in the transfer between the primary production server and the disaster recovery server.

Conditions on Use In order to use the software under disaster recovery rights, Customer must comply with the following terms:

• The disaster recovery server must not be running at any other times except as above.
• The disaster recovery server may not be in the same cluster as the production server.
• Use of the software on the disaster recovery server must comply with the license terms for the software.
• Once the disaster recovery process is complete and the production server is recovered, the disaster recovery server must not be running at any other times except those times allowed here.

Use of Windows Server Windows Server Licenses are not required for the disaster recovery server if the following conditions are met:

• The Hyper-V role within Windows Server is used to replicate Virtual OSEs from the production server at a primary site to a disaster recovery server.
• The disaster recovery server is used only to:
  • run hardware virtualization software, such as Hyper-V,
  • provide hardware virtualization services,
  • run software agents to manage the hardware virtualization software,
  • serve as a destination for replication,
  • receive replicated Virtual OSEs, test failover, and await failover of the Virtual OSEs, and
  • run disaster recovery workloads as described above.

Which I read as:

You don't need to license the servers serving as non-production/DR servers as long as they are only used for DR solutions. You can also test the DR solution and turn it on for up to 1 week every 90 days without paying extra in licenses.

Check your specific license model user rights and if necessary check with your license provider. They should be able to give a definitive answer.

Hope this helps

Ole