The NAS market is a truly mature market but is also a rapidly changing one. Its latest iteration, clustered or scale-out NAS—which allows the linking of multiple NAS devices under a single file system—has risen rapidly to meet the needs of organisations’ needs to store large amounts of unstructured data. But, there is still...
a need for traditional NAS products to meet the needs of SMB NAS use cases such as small business and departmental/branch office file serving.
While higher-end NAS products have gone scale-out/clustered, SMB NAS products have in some cases evolved to offer iSCSI and Fibre Channel block access connectivity options in addition to support for traditional NFS and CIFS protocols. In this they have arguably become multiprotocol storage subsystems, though majoring in NAS. Other products have remained true to file access and added performance enhancers such as SSD.
In this article we examine some of the current offerings in the non-scale-out SMB NAS marketplace for low and midrange use cases and its benefits for organisations that want to consolidate storage.
NetApp virtually invented the NAS product space, or at least made itself synonymous with it. Its FAS filer products can be linked together to serve files from multiple nodes, but there are severe limits on this capability, and so it is not a truly scale-out NAS product set. Products start at the entry-level FAS2000 range. The FAS2020, for example, offers 20 onboard disk slots, externally expandable to 68, and a total capacity of 68 TB on either SAS or SATA drives with Fibre Channel, Fibre Channel over Ethernet (FCoE) and iSCSI connectivity as well as NFS and CIFS file access options. The hardware comes bundled with an extensive range of NetApp software, including options for thin provisioning, snapshotting and data deduplication. Optional extras can be added, such as remote-volume mirroring. Dual controllers in the same chassis powered by the NetApp Data Ontap operating system provide failover in the event of controller failure. The range extends to include full-scale enterprise systems in the FAS6000 family via the FAS3000 midrange devices.
EMC’s Celerra NX4 combines traditional NAS with iSCSI and optional Fibre Channel connectivity and has the option to add a second X-Blade controller for failover capability. It has a maximum disk capacity of 60 drives, which can be SAS, SATA or a mixture of both; built-in file system deduplication; virtual provisioning; automated volume management; and fully automated storage tiering. The NX4 is the only unit in the Celerra storage range that does not feature the Celerra Multi-Path File System (MPFS), which allows scale-out NAS deployments. Consequently, it is billed as an entry-level storage system.
HP’s X1000 G2 Network Storage System is slightly less feature-rich than NetApp’s FAS2000 series and EMC’s NX4. Powered by Windows Storage Server 2008 R2, it offers iSCSI connectivity and can be managed by HP X1800sb G2 Network Storage Blades. The X1000 has a maximum raw capacity of 24 TB with either SATA or SAS drives. Its feature list also boasts file deduplication, quota management, file screening, reporting, Microsoft Windows Volume Shadow Copy Service (VSS) snapshots, Windows Active Directory integration and Windows Distributed File System (DFS) Replication. In HP environments, administrators can make use of integration with other HP products, such as the HP BladeSystem.
IBM’s N-series system storage NAS range is OEMed NetApp hardware and so offers iSCSI, NAS and Fibre Channel connectivity. The N3000 Express is the entry-level system of the N series and is presented as a consolidation solution for data formerly held in direct-attached storage (DAS). The rebadged FAS2020 unit offers SAS or SATA disk types and features the NetApp Data Ontap operating system, which manages thin provisioning and dual-controller options for data protection. This fits into a 24 TB array, which comes standard with the initial N3000 2U unit. The N series allows interoperability with external storage units and controllers from higher up in the range. The N series is an affordable small and medium-sized enterprise (SME) NAS solution that can be scaled up easily to an enterprise-level array with minimal migration pain.
Dell offers a number of NAS and multiprotocol storage product families, including the NS and NX product lines. In the NX series, the entry-level model is the tower-format NX200, which provides capacity of up to 8 TB on four hot-swappable SATA drives. The NX4 is a rebadged EMC NX4 and offers NFS, CIFS, iSCSI and Fibre Channel access in a 5U rack with as many as 120 TB of SAS or SATA drives. Meanwhile, the NX300 is NAS protocol-only, 1U in size and provides up to 8 TB of internal capacity. The NX3000 and NX3100 offer CIFS and NFS access, with optional iSCSI access on the NX3000. Both are in the 2U rack-mount format, with 24 TB of internal capacity on the NX3100 and 12 TB on the NX3000. Dell’s NS products are rebadged EMC devices, providing NFS and CIFS file access with iSCSI and Fibre Channel block access. They come in an 8U rack-mount format; the NS120 offers expandable capacity up to 120 SATA or Fibre Channel drives, while the NS480 can scale to 480 drives.
Nexsan announced the launch of its E5000 NAS range in August this year and has taken an interesting approach to differentiate its product range from competitors. Rather than adding block data functionality, the company has concentrated on file system performance optimisation, and the E5310 (the midlevel system in the range) showcases Nexsan’s FASTier SSD cache for high-speed data access. The E5310 features a maximum of 240 externally connected SAS or SATA disks, with a maximum capacity of 720 TB, and an SSD cache consisting of two 100 GB drives, with an additional 8 GB of DRAM cache. Thin provisioning, snapshotting and replication features come standard, and dual-controller options can make the system resilient against hardware failure. Readers should note the entry-level E5110 system does not support the SSD caching feature available in the higher-level models.
The SnapServer NAS range from Overland Storage is set at a similar market level to the HP X1000. It is powered by GuardianOS, developed by Adaptec, from which Overland acquired the SnapServer line in 2008. The SnapServer N2000 unit is stackable up to six units with a maximum capacity of 12 drive slots per array. The system supports either SAS or SATA drives and offers NFS and iSCSI connectivity options via dual 1 Gbps Ethernet ports. Snapshotting is included via Microsoft Windows VSS. Replication services are an optional extra via the Snap Enterprise Data Replicator add-on.
While not offering the extended capabilities of scale-out NAS, the SMB NAS products here still have an important role to play in SME system environments. NAS systems have evolved from being dedicated NFS/CIFS file serving solutions into products that also offer block-level storage. This extended functionality is now within the reach of SMEs and will allow them to address their data consolidation needs whilst also offering a cost-effective storage platform for virtual server environments.