Secure Multi-Tenancy (SMT) provides complete secure isolation between Storage Virtual Machines (SVMs) in an ONTAP Cluster. This makes ONTAP platform ideal when they are multiple tenants using it as a shared platform. ONTAP provides this capability by logically separating SVMs using IP Spaces so that inbound and outbound network communication intended for an SVM is not accessible from another SVM on the same storage platform or within the ONTAP cluster. There is also third-party certification which validates this claim.
The Common Criteria certification for ONTAP 9.3 provides an overview of the Target Of Evaluation (TOE) which includes information on domain separation.
Domain Separation: The TOE can function as a storage server for multiple groups of users within the TOE's control that must remain isolated from one another through the implementation of SVM technology.
In addition, a third-party audit that validates ONTAP SVM having an SMT capability can be found in TR-4512: NetApp Secure Multi-Tenancy (SMT) Validation Report.