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Everything you need to know about Windows Server 2019 Client Access Licenses (CALs)

Windows Server 2019 Client Access Licenses (CALs)

HPE ProLiant Gen10 servers and Windows Server® 2019 were made to work together, giving customers more flexibility, enhanced security, and innovation. With the end of service for Windows Server 2008 and the release of Windows Server 2019, many of your customers are probably upgrading to the latest servers and operating system (OS)—which is resulting in a lot of questions about client access licenses (CALs).


First, remember that Microsoft® moved to a core-based licensing requirement (instead of processor-based licensing) starting with Windows Server 2016, and that’s still in effect with Windows Server 2019. Core-base licensing helps customers better align costs with their server performance requirements, and also better enables the transition to hybrid and multicloud IT. But core-base licensing is just the beginning.

When a customer purchases a Windows Server license, that gives them the right to install the OS onto the server. However, the Windows Server license does not give them the legal right for users or devices to connect to that server. So, in addition to the Windows Server 2019 license, customers also need to make sure they have the right number and type of CALs in place. The only exception is for customers with a Windows Server 2019 Essentials Edition license, which does not require CALs.

While this might seem like a confusing way to handle licensing, it’s actually better for the customer. It enables Microsoft to offer a low entry price and allows customers to only pay for what they use, making an enterprise-class OS more affordable for a wider range of organizations.

User CALs or device CALs: Which is best?

There are two types of Windows Server CALs—one for users and one for devices.
Here’s how to decide which is best for a given situation.

·   Device CALs allow an unlimited number of users to access Windows Server from a single device. So, only one device CAL is required for each device, no matter how many users access it. This is the easiest and most economical choice if there are multiple users per device, such as a call center or other type of shift work where several employees share the same workstation. As a rule of thumb, if there are fewer devices than employees in an organization, this is the right choice.

·   User CALs allow a single user to access Windows Server from an unlimited number of devices. That means one CAL is required for each person accessing the server, no matter how many devices that person uses. This is the most economical choice if your customer has remote or mobile employees accessing the network from multiple or unknown devices. In other words, if there are fewer employees than devices, this is probably the right option.

Do I need Remote Desktop Services (RDS) CALs?

Some customers may need RDS CALs in addition to user or device CALs. An RDS CAL is required for users or devices who access Windows Server 2019 remotely using RDS.

What version of Windows Server CALs do I need?

Windows Server CALs must be the same version as the server software they access or later. So, users or devices accessing a server running Windows Server 2019 must have Windows Server 2019 CALs. Windows Server 2019 CALs may be used to access Windows Server 2016, but Windows Server 2016 CALs cannot be used to access Windows Server 2019.

How are Windows Server CALs sold by HPE?

Once you’ve determined the right number and type of CALs, they’re available from HPE or an authorized partner in packs of 1, 5, 10, and 50 for user and device CALs and packs of 5 for RDS CALs. CALs don’t require a new server purchase, they can be obtained at any time—and should be assessed regularly as the number of users/devices grows.

If you are a reseller, be sure to check in with your customers to ensure they have all the CALs needed, as requirements can change as businesses grow. If you're a customer, now is a great time to check to ensure you're in compliance.

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Willa manages the HPE | Microsoft Coffee Coaching program. Follow along to learn more about the latest HPE OEM Microsoft product releases and how the HPE Microsoft partnership can benefit partners and customers.