NAS Drives for your Home or the Small Office
Introduction
It is not uncommon today to have multiple computers at home. The small office home office or a office in the small and medium segment will have a few machines connected together in a LAN. It is a given that our data needs have grown. Even at home we have a movie collection, music collection, photo collection and of course a bunch e-mails and other stuff. The offices have their own storage needs.
Direct attached storage (DAS) or a drive attached to the individual machine used to suffice. Today you may be using multiple machines and have data synchronization problems. Besides you may want to share things between family members. In offices you certainly have a need to share things. In all such cases, it is good be networked. Rather than trying all kinds of mapping of individual drives to be mapped and shared it is nice to have a centralized unit where everything can be stored. This needs to communicate with individual machines of course. A nice high capacity storage system that simply attaches to the LAN is a solution in such cases. These boxes are the so call network attached storage or NAS drives.
Desirable specifications
The most important specification is that it should be network-ready. Since the drive has to support streaming video, streaming music and other processes simultaneously it has to be a complete network device. For the sake of performance, it should be able to support the speediest network. It should be the Gigabit Ethernet support.
Next most important specification is the capacity. As we all know, basic capacity is not a problem these days. So more storage we can get for money is good to have. Typically, it’d be a couple of TB of storage capacity that should be good for the given context. This capacity is usually built up by using multiple drives. Whether single or multiple drives, what is an important specification for capacity is the protection against crash. Easy back up and restore is essential. When a crash actually occurs restoration can be a major pain still. Unless the back up took place exactly before the crash, there is always some data loss. Ideal then would be something that can reconstruct my data completely.
We are into RAID territory then. RAID 1 creates a complete copy on a second disk so that only about half of the total capacities of the two disks are available for use. A complete copy of data is reconstructed easily as it is always available on disk two. RAID 0, 5 and 6 stripe data across available disks and use some extra data bits for redundancy. Therefore there is no significant capacity loss, yet data can be reconstructed in case disk loss. RAID 5 data can be reconstructed in case of one disk loss of an array of disks, RAID 6 can get your data back even when two drives go out at the same time.
Read/write times are the most important performance parameters. You should always check out the storage system under your usage conditions. Typically, this would be a few streaming operations simultaneously with large file transfers. Time taken to read or write a large file when the other streaming operations are going on simultaneously is a good indicator of average read and write times you are going to see.
Most such devices have USB ports attached to the NAS boxes which allow you to attach additional devices such another disk or a printer. We take a look at some actual devices that are good for this role in the following.
Representative Devices
The characteristics as discussed above for a few commercially available devices are described here.
Maxtor Shared Storage II:
Network: Gigabit Ethernet
Capacity: Enclosure holds 2 TB of data in two drives. Can be RAID 0 or 1.
Others: Back up & restore, web Interface, 2 USB ports for expansion and printer. Prices around $600.
Iomega StorCenter ix2:
Network: Gigabit Ethernet
Capacity: The enclosure can hold 2 drives in either RAID 1(mirror) or JBOD (just a bunch of drives). In this configuration it is one logical drive with a total capacity of the two individual drives inside the enclosure. Total capacity can be up to 2x1 TB.
Others: Scheduled back up & restore software, Price $299 for 1 TB device to $479 for 2 TB device.
Promise SmartStor 2300N:
Network: Gigabit Ethernet, 2 ports
Capacity: The enclosure can support RAID 0/1 with 2 drives. The model 4300 has 4 drive bays, 1 is a hot standby. You can add drives you choose to and the capacity would depend on that. With 1.5 TB drives, the 2300 can have a capacity of nearly 3 TB in RAID 0 configuration. 1.5 TB in RAID 1.
Micronet MaxNAS RAID iSCSI:
Network: Gigabit Ethernet, 2 ports
Capacity: The enclosure can support RAID 0/1/5/6 or JBOD, just a bunch of drives. Up to 5 drives, included in the system. Total capacity 2.5 TB, 5 TB and 7.5 TB in 3 models.
Others: Back up & restore software, 3x USB ports, Hot swappable drives, iTunes compatible audio streaming server, Price $1349, $1699 and $2499 for the three models.
In general, reads are a little slower that writes on these devices. Some perform better when small files are being transferred, others in a multimedia scenario when video or photo transfer operations are being done. The first one would be suitable for a office while the ones good for multimedia mix will be good for your home use. None of the devices stand out on performance, they are more or less similar. Intel NAS Performance toolkit (https://software.intel.com/en-us/articles/intel-nas-performance-toolkit/) is a benchmark suite that can be tweaked to test out devices in your actual use scenario.
