Hello
Thank you for your question and reaching out.
You wouldn't need anything else if you were using User CALs and the Users already had CALs. User CALs, which are obviously not required for Linux machines, cover every Windows server on the network.
However, they would require Device CALs if you were using them.
Every Workstation (Windows, Linux, Apple, or other) that utilises any service from a Windows server will still require a CAL. Even your Linux server will require CAL protection. It's unlikely that using a remote terminal through an intermediary host will eliminate the need for those CALS.
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