To get Microsoft documentation that explicitly characterizes Azure Stack as a closed-box system, focus on key themes like restricted access, vendor-controlled infrastructure, and sealed appliance architecture.
This Stack Hub document underscores the vendor-locked integration and the lack of user control over the underlying infrastructure, aligning with the closed-box system concept.
Azure Stack Hub is delivered as an integrated system, the security posture of the Azure Stack Hub infrastructure is defined by Microsoft. Just like in Azure, tenants are responsible for defining the security posture of their tenant workloads. This document provides foundational knowledge on the security posture of the Azure Stack Hub infrastructure. Azure Stack Hub infrastructure security controls
This document indicates that hardware updates are managed through OEMs, and users have limited control, consistent with a closed-box system.
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