Does anyone know if we need to purchase a Windows Server CAL for each device with Radmin Viewer? We're using it to remote into Windows Server console sessions. Thanks for any insight you may have on this topic.
No, you don't need to purchase any additional MS CAL's.
From a Microsoft Licensing standpoint, logging into the server console using RAdmin is exactly the same as if you were sitting in front of the server physically and logging on - i.e. covered by your existing licenses.