PowerFlex File Controllers (sometimes called File Nodes) are the physical nodes that enable the presentation of PowerFlex software defined File Services. They host the NAS Servers, which in turn host the tenant namespaces and file systems, mapping PowerFlex volumes to the file systems presented by the NAS Servers. All major protocols are supported: NFS, SMB/CIFS, FTP, NDMP, and so on. Moreover, the NAS Servers support multiprotocol access to the shared file systems.