Icy Box IB-RD4320StU3 External RAID Storage Enclosure for 2x 3.5 inch SATA HDDs with USB 3.0 interface

I recently got to the point where my PC's data storage disc was almost full (1.3TB of a 1.5TB disc) which left me the option of another internal disc or investigating some external storage. Having previously bought a dual drive external hard drive enclosure, the advantages were obvious to me (and if nothing else, in the event of having to race out of the house in an emergency, picking up the drive enclosure would be far easier than picking up the PC).

I settled on the Icy Box enclosure, having previously bought their products and been pleased with the performance and styling. The item arrived within a few days of ordering and as usual, the item arrived packed in a second cardboard box (I appreciate the touch, Amazon, but question whether it was strictly necessary or environmentally friendly).

On opening the retail box the contents were neatly packaged and held in place by an internal foam scaffold. The enclosure itself looked comparatively small and was made out of what looked and felt like black-anodised aluminium, with a silver surround to the grille of the fascia and was very light. However, when set up against my old USB2 external enclosure, the USB3 enclosure was pretty similar in size, although it was lighter than its USB2 cousin. It came with an external mains power supply (clearly it's not USB powered) and a USB3 lead as well as a small booklet containing multi-lingual instructions.

Installation of the SATA hard drives was a rediculously simple affair: the fascia unclipped from underneath, lifted up and off the front revealing two slots behind it (think of a typical 2-slot toaster). Orientated correctly, the drives slide in easily and require nothing more than a small push to make sure the ports at the rear seat into the connectors in the enclosure. Then the fascia is replaced with a slide and click. There: done!

Connecting the enclosure to the power supply and the PC (via a PCIe USB3 expansion card) was painless, as was turning on the power switch on the back of the enclosure. It seems that by default turning on the power also turns on the integral fan which doesn't make the unit silent, but doesn't add appreciably to the relatively minimal noise my PC generates anyway. After a few more minutes of configuring the drives in Windows (Win7 64bit), I had both the installed 2TB Seagate EcoGreen drives available (about 1.85TB each after formatting) and I transfered the data from my congested internal data drive to the external enclosure. I have to admit that the enclosure did become quite warm during the transfer - not hot, but very warm. However, the data transfer rate was pretty rapid (I seem to recall seeing a burst rate of 105MB/sec initially, but which settled to a rate of 65-85MB/sec). In routine use the amount of data shuttling in and out of the discs in the enclosure is far less and I've not noticed as dramatic a temperature rise (at idle it's barely warm, and cooler than the USB2 enclosure it sits next to).

The status lights on the front flash to indicate activity, as well as providing some trouble-shooting capability for faults (for which, read the booklet). At the back are some dip-switches which allow you to configure the unit for various RAID modes. My enclosure came with JBOD set up as default which I elected to continue using to get the full size of the installed discs, so I can't comment on the RAID functions. However, the booklet reports RAID 0 and RAID 1 to be available (and changing RAID mode requires a reformat before use), while the unit apparently has no limit to the size hard drives it will accept. Additionally, there is a Kensington lock slot at the back: nice touch, but as far as I can see it doesn't prevent anyone popping open the fascia and removing the hard drives.

In the month since purchase the unit has behaved impeccably and has given my PC much needed breathing space. Based on my experience so far, I can easily recommend this product to anyone needing a USB3 capable, dual hard-drive external enclosure, and even more so if the price falls below the £[] I paid for it.

I ordered this with 2 3TB hard drives but the drives were not in stock with the chosen supplier; a second supplier based in Germany was later selected but delivery has yet to be made. As I now use a 64-bit version of Windows 7, I can use drives larger than the previous 2TB limit with all recent 32-bit versions. Fortunately, I did have a couple of nearly identically sized disused 500Gb alternatives to hand as a temporary measure. One thing not made too clear is that the unit currently supports only SATA-I and SATA-II drives; others cannot therefore be used. If a faster SATA drive set is essential, you will need to look for an alternative solution.

I had repeatedly considered adding either an NAS/RAID combo unit or a simpler RAID unit to my hardware set-up. There are advantages and disadvantages to both but, currently using a single PC most of the time and only rarely using another, a network approach was considered less essential. But it is a solution I may return to at some future date as and when my needs should change.

I have used a variety of drive capacities over the years for my backups, getting progressively larger more or less every second year as the operating systems grew exponentially, and the range and volume of installed 'everyday' software has also increased. I have broken down my backups into a System set to guard against either a system HDD failure or system corruption, both of which I have experienced. The second series of backups covers my data sets, broken down into various groups, photos, music, database files, essential downloads and so on. To further complicate matters, I use an incremental system whereby I have a base backup file which is added to by a weekly file of changes and additions. This is preferable for several reasons than a series of separate complete backups.

Unpacking the unit from its considerably larger carton, provided the first surprise - the unit is really quite small. Initial assembly requires that the unit is not connected to power. Remove the front cover by sliding a lock slider at the base and the front then slides off revealing two open slots with guide rails to help alignment. The connection sockets for the drives are at the back, basically mirror images of each other. The drives need to be inserted with the manufacturer's labels facing each other. Gently press the drives to engage with the connectors. Springs on the front panel when it is replaced and locked help ensure the connections and perhaps reduce vibration.

The next stage is to choose the operating mode - three are on offer; RAID 0, RAID 1 and JBOD. Selection is made by amending the position of the two small switches according to the instructions within the manual and on a nearby label. A small screwdriver or similar may be needed as the switches are small and quite deeply recessed. Each of the available modes provide different capacities, writing/reading speed and security. RAID 0 demands a pair of identical drives, offers data striping with the data alternately written in small chunks first to one drive and then the other, but there is no redundancy or security, but the capacity is basically the sum of the two. Should one drive fail, the data set is irrecoverably lost. The unit cannot be used until the faulty drive is replaced. If the capacities differ, it is the capacity of the smallest that is used for both.

RAID 1 uses the same drive pair as RAID 0, but the data is written in entirety to both drives, more or less simultaneously. Consequently, the capacity is that of one drive alone but there is full redundancy. Should one drive fail, that can be replaced and the data on the survivor is used to recreate that on the replacement but the data is fully accessible in the interim. Adding or amending data is obviously not recommended until a replacement drive is installed, as the CRC data will have been altered.

JBOD (just a bunch of drives) can use two or more drives of whatever individual capacities that happen to be available. There are two modes that different manufacturers sometimes describe as JBOD; the correct definition is that the drives are seen as distinct entities, each with its own drive letter and capacity. The alternative, strictly described as BIG or Concatenated, shows the two as a single drive with the capacity of the two combined, although the drives retain a separate hidden identity and the second is used only once the first has been filled. Icy Box do not make clear which mode is actually employed by this unit, not in the manual or on their site, and I would assume that it to be true JBOD. I did not try this out so cannot confirm either way.

Once the mode is selected, there is a small CONFIRM button that needs to be pressed once the unit is under power. There are three indicator lights under the front panel to indicate operation and also by change of colour or pulsing, any problem or drive failure should something occur. Once the unit is switched on, the drives need to be partitioned and formatted before first serious use. The unit may not be ready for use for some hours if the more traditional methods are used, but this will be longer with increasing drive capacity. I would therefore suggest using Windows Disk Management tool that does both in seconds, regardless of drive capacity. If, at some future date, you decide to change the mode originally selected you will need to backup the data elsewhere as it will otherwise be lost as changing the mode demands that both drives be repartitioned and reformatted.

The USB 3.0 lead is rather short at about 1m in length but longer ones, or an extension, can be purchased if needed. The power lead is equally short so the unit may need to be placed close to a power socket.

There is an internal fan which is not switch-controlled, on or off, or speed adjustable as with other rather more expensive alternatives. It can be a little noisy, but not excessively, so you may want to position it to one side or the other. However, after a lengthy period on non-use, the fan will switch itself off.

Pricewise, it is an excellent introduction to the use of RAID. There are other, more advanced and more secure RAID types that use 4 or more drives but the cases are consequently larger, their internal controllers more complex and the complete assemblies considerably more expensive, often well over £1000 not including the cost of the drives. For use with this unit, some users may well choose to buy a third drive as a spare from the outset to maintain the match. Later series may be of slightly different capacity and some of that capacity may then be wasted.

A simpler RAID solution, comfortably priced, easy to assemble and use, a sensible first offering and therefore recommended.

UPDATE @ 05-03-2012

The 3TB HDDs arrived today. I removed the 500Gbs that were used to test rather than as a real RAID volume and installed the WD 3TB Greens which are a much more snug fit than the Seagate/Samsung conbo first installed. Their existence was quickly recognised and the next task was to format. Not having ever used a drive larger than 2TB, I had forgotten that the use of MBR with which I am familiar limits partitions to 2TB and I first made the mistake of making that selection. However, Windows Disk Management tool allows conversion to GPT which uses the full capacity of the drive. With the GPT partition in place, a fast format created a usable volume/drive in a few seconds.

According to Icy Box's web site, the unit will allow use of drives with individual capacity larger than 3TB, but nothing any larger is currently readily available. If and when such drives are released, it is probable that they will use SATA modes other than I or II that the current enclosure supports for their better rates of data transfer.

As my initial tests were conducted without the front cover in place, it may be that what I thought to be fan noise was more likely either the drives' motor noise or a degree of vibration. With the new HDDs installed and the cover closed, the fan noise is negligible and not obtrusive in a slightly noisy normal environment.

I have the enclosure connected to a USB 3.0 socket but I cannot yet put the new RAID volume to a practical test pending completion of a scheduled backup series previously started under my previous drive regime. It will entail creating a new backup set with the new volume as the target. As total backup time would be around 10-12 hours, based upon known history, it is something I will set up to run overnight. I do not expect write speeds to be much less as RAID 1 that I have chosen entails duplicating the data across both drive units but read time should be much less, if solely due to the USB 3.0 bus.

UPDATE @ 7-03-12

I created a suite of backup tasks to correspond with the previous set, but now using the RAID enclosure as the target. I cannot give a precise overall time as I started just before midnight and left it to its own resources. The final job started just after 3am and I would guess that the overall time from start to finish was about 4 hours, about a quarter or third of the previous timings. This was with a USB 3.0 connection but it would be considerably longer had I connected it to USB 2.0. Writing a duplicate data set, under RAID 1, does not seem to impact significantly. This is not scientific as the data set was not precisely measured, and neither were timings, but it does provide an impression.

UPDATE @ 05-12

The enclosure used as RAID-I was not recognising one of its drives and did NOT flash one of the LEDs to show that a drive had failed (all are 9-10 weeks old). Read more ›

I bought this because I wanted a simple USB-connected hardware RAID solution, and that's exactly what I got.

The box itself feels fairly sturdy and looks quite neat, being pretty much the same size as a normal external hard drive, just slightly fatter (to accommodate 2 drives). The 3.5" SATA drives simply slot straight in to the front and a fascia clips in position to cover them.

A series of 3 status LEDs on the front are bright and easy to see so it's simple to verify that the device is working.

You can set RAID 0 (striping, so that effectively the two disks appear as one single disk with their combined capacity), RAID 1 (mirroring, so that all your data is written to both disks simultaneously) or JBOD (just a bunch of disks, so that both disks can be used separately) by means of a small switch at the rear.

As this is a hardware RAID device the host computer operating system and the file system of the disks is irrelevant. I'm happily using this with a pair of 500Gb drives in RAID 1 configuration formatted as EXT4 and attached to my Ubuntu machine, which simply sees this as a single 500Gb drive presented on /dev/sdb1. It supports SATA hot-swapping so in RAID 1 config a drive can be pulled (or inserted) without needing to switch the device off, and the host computer carries on quite happily.

The only thing that slightly confused me is that when initially mirroring the newly-inserted drives, the small user manual says that the second disk's LED will flash quickly. However it flashes about once every 2-3 seconds which in my mind means a slow flash -- and the user manual says that a slow flash indicates a faulty disk. But after leaving it a few hours the flashing stopped and I've verified that both disks are readable and contain the same data, so I guess Icy Box's idea of slow and fast flashing isn't the same as mine!

Apart from that, a simple solution which Just Works. I'm considering getting a third identical drive so that on a weekly basis I can hot-swap one of the mirrored drives. This should give me a degree of redundancy just in case a drive fails, as well as a (potentially off-site) backup that should never be more than a week out-of-date.