Dell EqualLogic PS6210XS EqualLogic Group Manager Administrator s Guide PS Ser - Page 364

NOTE: Only an account with group administrator privileges can view or manage a NAS cluster. When you configure a NAS cluster, you specify the network configuration for the service and the amount of storage pool space for the NAS reserve. The NAS reserve is configured with Fluid FS and stores client data, in addition to NAS cluster metadata. The NAS reserve is divided into NAS containers in which you create SMB shares and NFS exports to make storage space available to users. NOTE: Depending on the NAS appliance model, the NAS member might show its controllers organized under the NAS member as a NAS controller pair. Both NAS controllers in a NAS controller pair operate simultaneously. Each NAS controller has a high-performance cache that is mirrored by its peer NAS controller. If one NAS controller in a NAS controller pair fails, the other NAS controller automatically continues operation with no impact on availability. Just as you can add arrays to a PS Series group to expand SAN capacity, you can start with one NAS appliance and then add another NAS appliance to the NAS cluster as a NAS controller pair. Adding a second NAS controller pair increases NAS cluster performance. You can create multiple NAS containers in a NAS cluster. NAS containers have robust security mechanisms and support snapshots and NDMP for data protection. On each NAS container, you can create multiple SMB shares and NFS exports. Clients with the correct credentials can access the shares and exports. Clients connect to NAS containers through a single NAS cluster IP address, providing a single-system view of the NAS storage environment. For availability and performance, client connections are load balanced across the available NAS controllers. A NAS cluster can serve data to multiple clients simultaneously, with no performance degradation. Clients connect to NAS storage through the NAS protocols of their operating system: • UNIX users access NAS storage through the NFS protocol. • Windows users access NAS storage through the SMB protocol. After the client establishes the preliminary connection, the NAS storage acts as a normal storage subsystem, accessed in the usual way by users or applications. The NAS cluster hardware and network configuration is described in detail in your NAS appliance hardware documentation and includes the following components: • NAS controller pair • Client network Used for client access to the NFS exports and SMB shares hosted by the NAS cluster. For security, the client network is typically separate from the SAN and internal network. • SAN/internal network Enables internal communication between the controllers as required for failover, communication between controllers, and communication between the NAS cluster and the PS Series SAN. The SAN/internal network is connected to the same set of switches. For performance and security reasons, Dell strongly recommends that this network be in a different subnet from the client network. A NAS cluster supports various network topologies. From a performance perspective, it is important to consider the subnets to which the clients belong (they might belong to more than one) and the subnets to which the NAS cluster belongs. For example, if the NAS cluster and all clients are on the same subnet, the network is considered "flat," which provides the best performance. If clients reside on a subnet that is not the same as the NAS cluster client subnet, the network is routed, and clients can access NAS container data by using a router or layer 3 switches. In a routed network configuration, you should configure multiple NAS cluster IP addresses for proper load balancing. 364 Reference: GUI Panels, Wizards, and Dialog Boxes