Windows servers are now licensed by core count. You'll also need windows Cals plus RDS Cals for each device or user. If you purchase from a microsoft reseller then you'll get the current version Server 2022 so if you need 2019 ask the seller to also provide a downgrade product key for activation.
Some general info
- Each host needs to be licensed.
- A minimum of 8 core licenses is required for each physical processor and a minimum of 16 core licenses is required for each server.
- Core licenses are sold in packs of two.
- Standard Edition provides rights for up to 2 Operating System Environments or Windows Servers containers with Hyper-V isolation when all physical cores in the server are licensed. For each additional 1 or 2 VMs, all the physical cores in the server must be licensed again.
- DataCenter Edition provides rights for unlimited Operating System Environments or Windows Servers containers with Hyper-V isolation when all physical cores in the server are licensed.
A Windows Server CAL is a license that grants access Windows Server. CALs are used in conjunction with Microsoft Windows Server OS licenses to allow Users and/or Devices to access and utilize the services of that windows server
- User CALs allow a single user access to any number of Windows Servers from an unlimited number of devices
- Device CALs allow an unlimited number of users to access any number of Windows Servers from a single device
- CALs are licensed to access servers of the same level and below. (not forward compatible)
Some info here on RDS Cals.
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