Sharing is good. Networks were created so people could share and communicate with each other, and network attached storage (NAS) provides an extra option that can often increase the benefits.
NAS refers to any device dedicated to storing files that can be accessed over a network by a group of users, usually through a number of standard network protocols.
It may sound simple, but it amounts to a full computer system capable of handling multiple high speed file requests, managing a file system with all of its oddities, and dealing with transmission control protocols (TCPs) and services you need to throw at it. All that demands a basic computer with a processor, memory, ports and OS connected to a bank of hard drives and networked via a LAN controller and sometimes wireless.
This means that a NAS has a specification beyond its storage capacity. The processor, for example, will dictate the maximum speed and number of requests that the device can handle. NAS devices can be based on everything from low power ARM or Intel Atoms processors to those for a full desktop, depending on the class of the device.
NAS models come in basic sizes based on the number of drives that can be installed. Home and small business models will only use a single internal drive, which limits capacity and does not provide the security that can be obtained with multiple drives when some are redundant.
The next step up is to dual-drive models. These can work as storage and, more importantly, as two mirrored drives storing identical data, so if one drive fails no data is lost.
Small and midsized businesses are more likely to need a redundant array of independent drives (RAID), using four or more to increase their storage capacity and provide data integrity through a number of error checking schemes. If one or more drives fail the RAID can continue to function without interruption to services, while the failed drives are replaced. The number of drives required increases as the specification increases.
At this level you can expect to see multiple gigabit LAN ports, which can be used for load balancing, redundancy if a port falls over or split network domains. It is also possible, if the business has the right infrastructure in place, to provide options for a 10GbE Ethernet through add-in cards or by default.
Moving beyond these standalone NAS boxes, larger businesses will be looking at rack based systems and enterprise level scale-out NAS solutions. These effectively virtualise the NAS storage as a pool, so it is easier to maintain and update multiple racks without worrying about the stored data.
Back-up power supplies and batteries, alongside multiple gigabit and 10GbE port adaptors can all be offered at this level. Storage on racks can reach the 1,000Tb levels if required.
A NAS will provide a wide number of services, ranging from standard network connectivity with support for standard file sharing protocols to internet services like FTP and HTTP. Back-up services are another core feature, and more advanced systems support iSCSI protocols that extend file transfer commands over an IP network for a SAN, and certification for virtual environments such as Microsoft Hyper-V help expand a growing SMB.
1. QNAP TS-879 Pro
Designed for the larger end of the SMB market, the QNAP TS-879 Pro is an accomplished eight bay NAS.
It has eight hotswap bays for flexibility and an Intel Core i3 processor, supports the latest 6Gbps SATA III interface, offers a pair of USB 3.0, four USB 2.0, two eSATA ports and a PCIe slot. This last item supports a dual-port 10GbE add-in card or additional dual-port gigabit adaptor, running alongside the existing dual-port gigabit LAN port.
The front mounted hot swappable drive bays are securely locked and the front USB 3.0 port provides a 'Copy to' button. The dual-port gigabit ports can be configured in a number of ways including fallback, load balancing and split network modes with full dual IPv4 and IPv6 support.
Beside the usual user management for security there is AES 256-bit volume-based encryption, HTTPS support and SSL/TLS FTP transfers.
Fired up with 10GbE connections, the QNAP TS-879 Pro can touch 600Mbps for file transfer, although with GbE it's a solid 110Mbps all the way.
If you've invested in a 10GbE infrastructure then the QNAP TS-879 will deliver. Also, a rackmount model is available with the QNAP TS-879U-RP.
2. Synology DiskStation DS1812+
Designed for any business wanting copious amounts of storage, the Synology DiskStation DS1812+ is an eight bay NAS capable of being expanded up to 18 via two additional DX510 units. With SATA II 4Tb drive support, this offers a maximum base capacity of 32Tb and a maximum expanded capacity of 72Tb with a file system limit of 108Tb.
Alongside this it offers two USB 3.0, four USB 2.0 and two eSATA ports. It's running a 2.13GHz dual core processor and is kitted out with 1Gb of memory.
For networking it offers dual port gigabit LAN connections. These can be run in either a redundancy or load balancing mode with a suitable switch.
In redundancy mode this will limit transfer speeds to just over the 100Mbps mark, but with load balancing it will go up to 195Mbps average read and writes.
The Synology DiskStation Manager software offers RAID 0, 1, 10, 5 and 6, beside an utterly comprehensive list of services, management and virtulisation support for VMware, Citrix and Hyper-V. It only sits below the QNAP TS-879 Pro model due to its lack of 10GbE support.
3. D-Link DSN-6120
For larger SMB and enterprise network storage the D-Link DSN-6120 offers a suitable 2U rackmount solution. Its 12-bay design can provide 48TB of SATA II storage and the system scales to 60 drives using four DSN-6020 JBOD expansions for a total 240TB of capacity.
Designed with data centres in mind, the D-Link DSN-6120 comes with speed and redundancy at hits heart. It has twin 500W PSUs, no less than eight gigabit LAN ports on two controller cards and 4GB cache cards per controller.
The PSUs, LAN controllers and cache can be all hot swapped if one should fail. Dual port 10GbE support is offered via replacement controllers, but at extra expense.
The D-Link provides all the core storage and network services you would demand: all the RAID modes through to 6 with global hot spare from a dual RAID controller, iSCSI SAN and visualisation support for VMWare, Citrix and Hyper-V. It also provides snapshot, cloning, rollback and remote duplication.
Thanks to its quad port controllers, even with a gigabit LAN connection, cumulative read speeds can touch 450Mbps and writes as high as 305Mbps, providing the throughput without the need for 10GbE infrastructure. It is well worth the investment when high redundancy, high throughput is required.
4. Iomega StorCenter PX6-300d
The six bay Iomega StorCenter px6-300d is an SMB level NAS suitable for distributed enterprise level businesses.
It's built around a compact, quiet chassis running a dual-core Intel Atom 1.8GHz processor with 2Gb of memory. Unusually for this level, it utilises an external power supply, which some users will not be keen on.
The hotswap drives cannot be locked but are covered by a basic front cover. Connection wise there's a single USB 3.0 and two USB 2.0 ports.
For network action are dual-port gigabit LAN connections that can be used in a redundant or load balancing mode with a suitable switch. The NAS uses SATA II and is limited to 3Tb drives for a maximum capacity of 18Tb.
With support for usual virtualisation standards VMware, Citrix and Hyper-V, iSCSI support for SAN use and straightforward encrypted volumes, on top of the basic back-up and network services, this is a well priced, well performing NAS for SMBs.
5. Thecus N4800
Despite the low price, the Thecus N4800 is a highly competitive and capable NAS drive, as long as the volume of storage is not an issue. Despite that its four hot-swap bays can still cater for a total of 16Tb.
Inside it's running a capable dual core 2.13GHz Intel Atom with 2Gb of memory. It has a built-in OLED status display, HDMI output and even comes with a mini UPS for safe shutdown without power.
Even at this price it offers dual port gigabit LAN connection with load balanced and redundancy modes. Dual stack IPv4 and IPv6 is in there. Connection wise you'll find one eSATA, two USB 3.0 and two USB 2.0 ports. There's even a single lane PCIe slot.
The management software supports RAID 0, 1, 5, 6 and 10 with full volume AES 256-bit encryption. Virtualisation support for VMware and Citrix is in there, along with support for iSCSI for SAN use. Cloud support is the usual Amazon S3, Dropbox and ElephantDrive.
6. QNAP TS-469 Pro
A four bay NAS that can support higher end needs, such as virtualisation standards and iSCSI for SAN.
Based around the dual core Intel Atom 2.13GHz processor with 1Gb of memory, it still retains the performance to keep up with demanding business needs.
The four loackable hot swappable drive bays support the latest SATA III 6Gbps 4Tb drives for a maximum 16Tb of storage. External connections are two eSATA, two USB 3.0 and 5 USB 2.0 ports.
A dual port gigabit LAN connection caters for the networking and can be run in the usual redundant or load balancing modes with a suitable switch. This means speeds can reach 220Mbps with load balancing and 107Mps with standard gigabit LAN port.
Given that it offers the same comprehensive cloud, back-up, encryption and other network services as the more expensive QNAP TS-879 Pro, this four-bay model seems excellent value.
7. Synology DiskStation DS712+
For the smaller end of the SMB segment or demanding home office user, the Synology DiskStation DS712+ provides a high end NAS in a tiny dual drive chassis. While there is no doubting the capability of this NAS, there is an issue around why you would opt for this dual drive model over a slightly more expensive quad model?
With the same styling as the far larger Synology DiskStation DS1812+, the pedigree of the DiskStation DS712+ shines through. Based around an 1.8GHz Intel Atom with 1Gb of memory, the NAS can support a maximum internal capacity of 8Tb, but can be expanded via the DX510 to seven drives and 28Tb.
Despite its diminutive size it has dual port gigabit LAN connection that in load balancing mode can top 180MB/s read and 105MB/s write, which is not too shabby. It does lack USB 3.0 but has three USB 2.0 and a single sATA port. Most importantly it supports all the network protocols and services of its big brother, including iSCSI and visualisation with VMWare, Citrix and Hyper-V.
If you can live with RAID 0 or 1 support for the base NAS, then there's little else here to criticise.
8. Imation DataGuard T5R
This Imation DataGuard T5R is an interesting NAS, as alongside its five locked SATA II drive bays is a SATA RDX cartridge drive. RDX is Imation's solution to the death of tape back-up, a hard drive in a removable, rugged cartridge.
The main bays are SATA II 3Gbps with support for 4Tb drives, providing a maximum of 20Tb. The RDX catridges sit alongside an eSATA, two USB 3.0 and three USB 2.0 ports. The DataGuard system supports RAID 0, 1, 5, 6 and 10 with iSCSI for SAN deployment.
Inside the NAS is powered by a dual core 2.13GHz Intel Atom with 2Gb of memory. A dual port gigabit LAN connection can happily hit 100Mbps.
Good cloud support helps makes the Imation DataGuard T5R a good all round back-up solution with Dropbox, Amazon S3 and OpenStack support. The inclusion of RDX could make this attractive to some businesses and it performs well, but otherwise it lacks services provided by many other NAS models and it is costly.
9. Netgear Ready NAS NV+ v2 RND4000
The Netgear Ready NAS NV+ v2 is classed as a "prosumer" device by Netgear, but remains suitable for home offices and the smaller end of the SMB segment when low demand expanded shared network storage is required. With four removable SATAII drive bays the Netgear RND4000, to use its Netgear codename, supports 3Tb drives for a maximum capacity of 12Tb. Currently 4Tb are not on the comparability list.
Based on the slower 1.6GHz Marvel ARM processor with 256MB of memory, it's not going to provide the raw power to handle demanding environments. It does support RAID 0, 1 and 5 plus the Netgear X-RAID2, which makes on-the-fly upgrades very easy. Impressively there are three USB 3.0 ports and a single USB 2.0 port installed.
A basic software back-up solution is provided. CIFS, NFS, FTP and HTTP network protocols are supported with DLNA for media streaming, which are the basics you'd expect.
In use sequential reads hit 80Mbps but writes suffered at under 40Mbps, showing the slower processor struggles with anything but basic access. The saving grace is that the build quality is solid, and at this price with its four bays it's ideal if you just want basic NAS storage.
10. Buffalo TeraStation Pro Rackmount
Built around a slimline 1U rackmount, the Buffalo TeraStation Pro Rackmount model comes in 8Tb or 4Tb models with its four hot-swap drive bays preinstalled. This might not be to everyone's liking, and only Buffalo's drive kits can be used as replacements.
This new range is built around a 1.66GHz dual-core Intel Atom and 2Gb of memory, so it's suitable for the SMB that's after increased storage capacity.
Dual port gigabit LAN connection caters for the networking connections and supports load balancing. While there are two USB 3.0 and two USB 2.0 ports beside this, iSCSI is not supported, which limits its usefulness in larger IP SAN environments.
In-use RAID 0, 1, 5, 6 and 10 are supported, along with automatic replication to a second TeraStation and Amazon S3 cloud storage. Performance manages to hit around 100Mbps read but writes seem to struggle. For back-up a ten user NovaBACKUP licence is thrown in.
The system supports the less useful 128-bit AES per volume. Buffalo seems to have taken a potentially useful product and hobbled it with its insistence on proprietary media, the lack of iSCSI functionality and mediocre performance.
