When the server is configured in UNIX security mode, it supports UNIX security for SMB and NFS clients. However, all security settings are saved with UNIX file attributes. As a result, NFS clients are always accessing files in native mode, while SMB clients are always accessing file non-native mode.
Note: With UNIX security mode, NFS users do not need to rely on the presence of a Windows domain controller (DC) in order to access files. As a result, they are fully isolated from potential DC failures.