@JamesPowell-6973 You would need Microsoft Defender for Endpoint. the updated document that you already found, mentions that the latest compatible OS
Windows server 2019 and Linux.
The other older documents will be updated to reflect the same information and avoid public confusion.
Once you have the License, you can use the Azure security center to onboard the servers to Defender for endpoint. Read option 2 here. Windows Server 2019, which must be onboarded via local script though.
The Security Center console displays Microsoft Defender for Endpoint alerts. but if you would like more detailed information or investigate further, you use Microsoft Defender for Endpoint's own portal pages where you'll see additional information such as the alert process tree and the incident graph. You can also see a detailed machine timeline that shows every behavior for a historical period of up to six months.
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