MS Windows Server 2019 Licensing FAQ (unofficial)
We’ve put together this FAQ to help you navigate through the Windows Server 2019 licensing options and to answer some of the most common questions related to Windows licensing in many deployment scenarios.
What editions are available with Windows Server 2019?
What licensing options are available for Windows Server 2019?
What additional benefits does Windows Server Software Assurance provide?
What is Microsoft Azure Hybrid Benefit for Windows Server?
How to license a Windows server under the Per Core/CAL licensing model?
What is an External Connector License?
How to license a container running Windows Server software?
What editions are available with Windows Server 2019?
WIndows Server is offered in the following editions:
- Windows Server 2019 Datacenter - for highly virtualized datacenters and cloud environments;
- Windows Server 2019 Standard - for physical or minimally virtualized environments;
- Windows Server 2019 Essentials - for small businesses with up to 25 users and 50 devices;
- Microsoft Hyper-V Server 2019 - free stand-alone product that contains only the Windows hypervisor, a Windows Server driver model, and virtualization components.
One of the major differences between Datacenter and Standard editions is the number of allowed operating system environments (OSEs) or Hyper-V containers. OSE is just a more general term for a virtual machine (VM). Windows Server Standard Edition license includes permission for two OSEs, Datacenter Edition - for unlimited number of OSEs.
For complete list of differences between the editions see the Comparison of Standard and Datacenter editions of Windows Server 2019 web page.
What licensing options are available for Windows Server 2019?
Windows Server 2019 Datacenter and Standard editions are licensed under the Per Core/CAL model. This model requires licensing all cores in a server with core licenses and licensing all users or devices accessing a licensed server with Client Access Licenses (CALs) or CAL equivalents.
For more detail about the Per Core/CAL model see the following question: How to license a Windows server under the Per Core/CAL licensing model?
Windows Server 2019 Essentials edition is licensed per instance under the Specialty Servers licensing model with no CALs required.
What additional benefits does Windows Server Software Assurance provide?
Software Assurance (SA) is an optional software support offering available through the Volume Licensing programs. SA must be purchased together with the product license and renewed on a periodic basis to remain active.
Windows Server SA provides many benefits, including:
- 24x7 Problem Resolution Support;
- New Version Rights - customers are entitled for a free upgrade to a new version of the software when it becomes available;
- Semi-Annual Channel Releases - customers may install and use Semi-Annual Channel releases, including both Pilot and Broad releases (SA coverage for both server and access licenses is required);
- License Mobility - for External connector only;
- Microsoft Azure Hybrid Benefit (see the next question for more details);
- Disaster Recovery Rights (see the Product Terms for detailed benefit explanation and conditions);
- Step-Up License - allows to purchase an upgrade from Windows Server Standard to Windows Server Datacenter.
For more information on these and other SA benefits, see the Software Assurance overview web page.
What is Microsoft Azure Hybrid Benefit for Windows Server?
Under the Microsoft Azure Hybrid Benefit (AHB) for Windows Server, customers may use Windows Server Virtual Machines on Microsoft Azure and pay only the cost of compute, excluding license and client access charges.
Each set of 16-core Datacenter or Standard Editions licenses are entitled to two instances of up to 8 cores, or one instance of up to 16 cores. Datacenter Edition licenses allow for simultaneous usage both on-premises and in Azure (Dual Use Rights). Standard Edition licenses must be used either on-premises or in Azure, although customers get 180 days of concurrent use rights while they are migrating their servers.
AHB can be applied either to new or existing Azure VMs. For more details about the process see the Azure Hybrid Benefit for Windows Server page.
Azure Hybrid Benefit also allows customers to use any number of instances on an Azure Dedicated Host server (Unlimited Virtualization Rights on Azure Dedicated Host) if customers allocate Windows Server Datacenter licenses with SA for all of the physical cores on that Azure Dedicated Host server. In this case concurrent use is permitted only during the 180 day migration period.
How to license a Windows server under the Per Core/CAL licensing model?
Windows 2019 server requires two types of licenses:
- Server per core licenses;
- Access licenses - Client Access Licenses (CALs) or CAL Equivalent Licenses.
Core Licenses :
The number of required core licenses equals
the number of physical cores on the licensed server, subject to a
minimum of 8 licenses per physical processor and a minimum of 16
licenses per server.
Datacenter edition allows to run an unlimited number of Windows server OSEs (VMs) on a fully licensed server (e.i., a server with all cores licensed with Datacenter edition).
On a server fully licensed with Standard edition customers are permitted to run Windows server software in two OSEs - one physical OSE and one virtual OSE. If the physical OSE is used exclusively to host and manage the virtual OSEs then an additional virtual OSE is permitted (two virtual OSEs in total).
Standard edition core licenses are “stackable”. Additional licenses can be assigned to a server to increase the number of allowed Virtual OSEs. Each additional set of licenses covering all cores on a server and satisfying the per processor and per server minimums permits two additional OSEs.
To estimate the number and cost of Windows Server core licenses required for different server deployment scenarios try our Windows 2019 Licensing Calculator
CALs :
There are two categories of access licenses: Base and Additive. Generally,
every user or device accessing a Windows server requires a Base CAL
or CAL Equivalent License. The Base CAL is called Windows
Server 2019 CAL. Access to some of the advanced Windows server functions requires
Additive CALs:
- Windows Server 2019 Remote Desktop Services CAL (Device and User);
- Windows Server 2019 Active Directory Rights Management Services CAL.
Additive CAL must be used in conjunction with a base CAL.
CAL Equivalent License means one of the following:
- an User subscription license (SL);
- an External Connector License (see the next question for more details);
- a CAL suite.
CALs may be assigned by users or devices, as appropriate. A user CAL allows access from any device by one user. A device CAL allows access from one device by any user.
CALs may not be used to access third party’s servers and only allow access to server software running on customer’s licensed servers.
CALs are version specific and allow access only to the corresponding version or earlier versions of the server software.
Multiplexing or pooling does not reduce the number of CALs required. To learn more about multiplexing and its impact on Windows Server access licensing see the Multiplexing - Client Access License (CAL) requirements brief.
CALs are not required:
- for access by another licensed server;
- to access server software running a web workload (public web sites) or High Performance Computing (HPC) workload;
- for access in a physical OSE used only for hosting and managing virtual OSEs;
- to access Windows Servers running in Azure environment (access rights are included in Azure per-minute charge for the Windows virtual machines).
What is an External Connector License?
Windows Server 2019 External Connector License (EC) is considered a CAL Equivalent License and used to provide server access for external users.
External users are defined as users that are not employees, onsite contractors or onsite agents of Customer or its Affiliates.
EC license is assigned per server and has no limit for the number of external users. Each physical server accessed by external users requires an External Connector license.
Note that external users can be licensed either with CALs or EC licenses. Customers may use a combination of User and Device CALs, and External Connector licenses as required. The decision to use CALs or ECs will depend on many factors, including:
- practical possibility of determining the number of external users;
- the cost of CALs for the external users vs the cost of ECs for all accessed servers.
Similarly to the “regular” CALs, there are two categories of External Connector licenses: base, called Windows Server 2019 External Connector and additive, such as:
- Windows Server 2019 Remote Desktop Services External Connector;
- Windows Server 2019 Active Directory Rights Management Services External Connector.
External Connector licenses are version specific and allow access only to the corresponding version or earlier versions of the server software.
How to license a container running Windows Server software?
Windows Server offers two distinct technologies for running containers - Windows Server Container without Hyper-V isolation (previously called Windows Server Container) and Windows Server Container with Hyper-V isolation (previously called Hyper-V Container). The difference between the technologies lies in the mode of runtime isolation: process or Hyper-V isolation, and therefore in different degrees of isolation between the container, the host operating system, and all other containers running on that host.
The two container technologies also have different licensing requirements. Windows Server Container with Hyper-V isolation utilizes a virtual operating system environment to host one or more Windows Server Containers. Each Hyper-V isolation instance is considered as one Virtual OSE for licensing purposes. On the other hand, Windows Server Container without Hyper-V isolation is a feature of Windows Server software and does nor require any additional licenses.
| Container Technology | Datacenter Edition | Standard Edition |
| Windows Server Container without Hyper-V isolation | Unlimited | Unlimited |
| Windows Server Container with Hyper-V isolation | Unlimited | Two |
Is Windows Server covered by License Mobility?
Windows Server licenses are not eligible for License Mobility through Software Assurance.
Customers may reassign a Windows Server License to another device, but not less than 90 days since the last reassignment of that same License, unless the reassignment is due to permanent hardware failure or loss.
Only External Connector licenses with active SA coverage are eligible for License Mobility.
How much do Windows Server licenses cost?
As per the Pricing and licensing for Windows Server 2019 page the approximate costs for different license types are as follows (US$):
- Datacenter Edition (16-core pack) - $6,155
- Standard Edition (16-core pack) - $972
- Essentials Edition (server) - $501
- 1 Device CALs - $34
- 1 User CALs - $42
The yearly Software Assurance cost can be estimated at 25% of the base license cost.
Core licenses are sold in 2-packs and 16-packs.