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Sans Digital MOBILESTORE Hard Drive Enclosure Review

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AkG

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Sans Digital MOBILESTORE MS2UTN+B Hard Drive Enclosure Review




Manufacture Product Page: MobileSTOR MS2UTN+B
Model Number: MobileSTOR MS2UTN+B
Availability: limited
Price: $129.99 US
Warranty: 1 Year


In the past we have looked at single enclosures with slow connection options (USB), single bay enclosures with blazingly fast connectivity (eSATA), we have even reviewed dual bay enclosures which had RAID options but were bottlenecked by the USB 2.0 limitations. Today things are going to be different for not only will be reviewing a dual bay enclosure with enough RAID options to put a smile on the face of even the most jaded of tech geeks; but a dual bay enclosure which uses the ultra fast eSATA connection.

Just recently we reviewed a single bay enclosure which offered speeds that if you have never worked with eSATA before would be down right magical (as A.C. Clark said :sufficiently advanced technology is indistinguishable from magic.) The only problem with it was it left us wanting more; more speed more power and above all else, more safety. This of course is a lofty goal to try and surpass as a single eSATA connected hard drive gives some darn nice speed.

The subject of today’s review is the Sans Digital RAID dual bay external storage enclosure, which has both USB and eSATA connectivity options. This enclosure not only supports the normal range of RAID modes such as Raid 1 and 0 but even has what Sans Digital calls Safe33 and Safe66. We will go into detail about what these new hybrid RAID modes are all about later in this review, but for now it is suffice to say which they have the potential to bring a whole new dimension to your typical external enclosure experience! The MobileSTOR (as we will call it in this review) is available at many US e-tailers at retails for about $130 and should soon be available here in Canada as well.

When looking at external enclosures the biggest questions which one has to ask are: is this enclosure worth the money and more importantly are two hard drives in RAID faster than one when connected via eSATA; or will its controller not be able to handle the load? Hopefully, by the end of this review we will be able to not only offer our opinion but provide you with the tools you need to make this decision for yourself.

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AkG

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Specifications

Specifications


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Packaging and Accessories

Packaging and Accessories




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The box which the MobileSTOR comes in has a very nice and clean looking packaging scheme. It has large pictures of the two models on the front, loads of details on the back and even includes an integrated carry handle. What as especially pleasing about this unit was the amount of details the information on the back of the box goes into. If one is lucky, usually all an enclosure package will include is the dimensions of the unit and the kind of hard drives it accepts. Well, we are glad to report not only is this information present but also it includes connection diagrams so first time buyers will know exactly what to look for when they go to hook up this unit. It is the small touches which really highlight how much time and effort Sans Digital spent in making their product as user friendly as possible.


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This commitment to ease of use continues with the interior layout of the box, as the very first thing you will see when you open the container up is the accessory box right there on the top for easy access and removal. Not only is the accessory box on the top but it even has two good-sized holes designed to make it a snap to remove it from the larger container. No one likes having to tear up the packaging box just so they can remove everything from the inside and this is one of the simplest, most elegant solutions which we have seen to date. The elegance is in the fact that this box not only is the carrier for all the included accessories but also a very sturdy second level of protection. If one gets a little too enthusiastic with the old box cutter when opening it, the most likely results will be a gash in the accessory box or at worse a damaged cable.


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Once you are finished marveling at the ingenuity of the Sans Digital's packaging and actually remove the accessory box from the top of the container, you get the next enjoyable surprise. Instead of just using bubble wrap or cardboard cut outs to stabilize the MobileSTOR in transit, Sans Digital has taken the overkill route and used two large molded pieces of Styrofoam to allow the MobileSTOR the luxury of blissfully floating in the center of the box. This means for all but the most severe of bangs, crashes and other assorted disasters not much will affect the MobileSTOR itself. Quiet honestly, anything which could damage the enclosure would probably be severe enough to literally destroy the packing box first.


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As one would expect from such a high end unit, the list of accessories is long and very complete. In fact it is suffice to say that anyone who expects lots of goodies or swag for their money will not be disappointed. You get the normal range of accessories such as mounting screws, an instruction pamphlet, power cord, and keys to open the hard drive doors, USB and eSATA cables; then on top this list you get NTI shadow copy backup software and even a PCI eSATA bracket which allows older non-eSATA equipped computers the ability to use one of their free internal SATA ports as a virtual eSATA port. The list of accessories is not only long and very complete, but the quality of the parts used is also top-notch. For many enclosures the very first thing a lot of people do is replace the included connectors with better, higher quality ones; for this enclosure this is not needed as the connectors are durable, long and flexible. What more could you ask for?

Overall, this enclosure has to leave even the most cynical and morose buyer with a good first impression. For the first time in a long time, there is simply nothing on first inspection which one can point to is was subpar.
 
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AkG

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Exterior Impressions

Exterior Impressions




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With its gently sweeping front curve to its minimalistic approach to power and drive indicators, everything about this enclosure screams elegance and refinement. There are absolutely no rough or sharp edges anywhere on this device and even the hard drive doors blend seamlessly from one to another. Even with just a quick glance one can instantly recognize that a lot of time, effort and money went into refining this enclosure from just another ugly black box into a true work of art.


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As mentioned, the front of the MobileSTOR is not your typical blunt nose affair; rather, it has a gentle incline to the top third which allows the necessary height of the rest of the unit to blend seamlessly into the drive doors. If you look closely on the front right of the drive doors, you will notice two small holes. The large hole is where the door locking mechanism is hidden from view. By inserting the plastic tooth pick looking key into this hole, the door handle pops open, allowing you instant removal of not only the drive bay but also the hard drive (if one has been previously inserted).

The smaller hole located slightly lower and to the right of the large hole is where the power indicator, drive failure and even drive activity LEDs are housed. While on paper this sounds like a lot of indicators crammed into a small area it actually works very well in practice and keeps the amount of glare from these LEDs to a muted and user friendly level. This is especially nice if you’re using this device in a darkened room as the LEDs are more than bright enough to do their jobs, but they will not make a nuisance of themselves and ruin your night vision.


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When the drive doors themselves are opened you can see hoe Sans Digital designed these doors with internal air flow in mind, for just behind the door handle of the drive tray are large vents which allow the rear exhaust fan to suck fresh air in and over the hard drives. This is great engineering and is a very subtle yet effective way of shaping internal air movement.

Above the drive doors is where the power LED indicator, high temperature and alert indicator are located. The temperature indicator is a very nice touch since you can visually check and see if the enclosure is overheating without resorting to software-based solutions. As an added bonus, to the right of these LEDs is a button marked “mute” and as the name implies it mutes the audible warning which sounds if/when the unit begins to overheat. Yes, as this information does suggest, not only does the MobileSTOR come with visual alerts when things get to hot but also audible warning as well. This was certainly a feature and once again reaffirms Sans Digital’s obvious commitment to customer satisfaction.


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The back of the MobileSTOR is, as usual, where all the various connectors, fan and RAID adjustment are located. As a nice addition a diagram explaining what each of the numbers on the dial mean is silk screened onto the back lower right hand corner in bold yet clear white lettering. The only issue we have with the idea of having a recessed adjustment screw for the RAID control is the fact that there is no pointer (or any indicator for that matter) on the screw head to give you a clear idea of whether the enclosure is in JBOD mode (screw at position 1) or Safe50 (position 5) for example.

For all you eagle eyed readers who noticed we did not include the usual power brick in the long list of accessories, fear not for it was not an oversight. This unit has a built in power supply and just like your computer you need only a regular computer power cord to connect this unit to your power grid. Of course we still recommend you use a UPS or at the very least a surge protector since a bad brown out or surge will fry this enclosure just as fast as it will fry your computer.

Overall a close inspection of the outside of the MobileSTOR just reaffirms our first impression that this is a very nice piece of kit. It also obvious Sans Digital took the time to get it right.
 
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AkG

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Internal Impressions

Internal Impressions



Please note that opening your enclosure will void your warranty.


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In some ways we believe Sans Digital may have taken the clean smooth look a smidgen to far, especially when it comes to trying to open this sucker up. Maybe it was done to dissuade people from opening the case up and accidentally frying themselves on the now-touchable power supply internals, maybe they’re just bashful. Either way the only way you can open this case is by first moving the four rubber feet and then removing the screws which they were hiding.


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With those hidden screws removed, one has to simply slide the black case covering off the back of the silver chassis. On a side note, this is one slick way of doing things and certainly helps contribute to the MobileSTOR’s clean looks.


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When the metal covering is fully removed, the very first thing which pops out at you is the internal power supply. For the little amount of juice this unit requires, it was surprisingly beefy with two nice-sized heatsinks strategically located to take advantage of the enclosure's air movement. Even more impressive was the end user replaceable fuse located in the lower left hand corner of the power supply board. This means, for whatever reason the fuse blows you could theoretically replace it yourself. We say theoretically because this will certainly void your warranty and we are certainly not recommending it as once the power supply is energized it is not something you want to be mucking around with.


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The only downside which we can see with this internal power supply was the use of Fuhjjyu capacitors. While these caps can be found in some computer power supplies they have been know to swell and fail if put into a high-heat environment. We are not saying these will fail (far from it in fact); but you should be aware of this potential negative before buying a MobileSTOR. Let us reiterate: this unit uses very little juice and should therefore put very little stress on the caps so the chances of failure are just as slim as if they were any other brand. After all, Sans Digital has their good reputation to uphold; and in more mercenary terms; if the failure rate was unacceptably high they wouldn’t be able to make a profit, now would they?


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When one has carefully removed not only the power supply and its plastic anti static shield but also carefully unplugged the power connectors from the back of the unit you can then remove the whole power supply from the chassis. By doing this, it allows you the option of then removing the control PCB from the unit. This is accomplished by simply removing a couple more screws and removing the controller board from the back of the chassis.


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The very first thing which stands out on the PCB is that there is a small chip “missing” from the back of the board (just above the reset button and RAID controller knob). This makes it fairly obvious this PCB is used in multiple enclosures and the missing controller chip is either a Firewire controller or a NIC. Either way, this is a tried and true method which manufacturers use to help keep costs down. After all, why stock 4 boards when you can get a better deal on four times the amount of one board? So if you have gotten this far on your own MobileSTOR enclosure A) don’t panic…it didn’t fall out B) if you're nuts enough to try this at home we take absolutely no responsibility for it…we won’t even dial 911 for you…so there.


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The heat and brains of the MobileSTOR is the Silicon Image 5744 “SteelVine” RAID Storage Processor. The 5744 was released in late 2007 by Silicon Image and it is this processor which allows the MobileSTOR the ability to have not only JBOD, RAID 1 or RAID 0 capabilities but also SAFE33 and SAFE50 features. The 57xx series is the 2nd generation of the processor family called “SteelVine” and builds upon the initial success of the 47xx series. These controller chips are capable of supporting 3GB/s “SATA 2” hard drives and when bought in large quantities go for about $5 USD each. Needless to say these are very high end controller chips and it was great to see it being used as the controller for the MobileSTOR. It will be interesting to see how this controller chip’s test results stack up against not only previous eSATA enclosures tested but also USB controllers as well.


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The active cooling of the MobileSTOR enclosure is provided by one Y.S.Tech FD124010LB 40 x 40 x 10 mm fan which is capable of moving 4.3CFM of air. While this doesn't sound like much air movement, hard drives really do not need active cooling so any air movement at all is more than enough. This helps explain the temperature warning indicator located at the front. Of course, this lil’ guy is only held in place with the two screws and uses a standard 3 pin connector; so it can be easily swapped out for a more high performance fan if the need should arise (say cooling a pair of Raptor 150s). One thing worth mentioning is this fan is actually fairly loud; when we looked up its specifications we were shocked as we were expecting a high performance fan to justify its noise output. Don’t get us wrong, it is no where near buzz saw levels but it is louder than Scythe E fans.
 
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Installation

Installation



Unlike other enclosures which we have reviewed in the past, MobileSTOR requires tools for proper installation. Namely, it needs a good old fashioned Philips screw driver, which is not included. Actually, we are getting a little ahead of ourselves here so let’s start at the beginning of the installation process.


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To install a hard drive into this unit the very first thing one must do is open the front door on one of the two drive bays. As mentioned earlier in the review this is accomplished by using the small plastic key and inserting it in the front door opening hole. You will instantly know when you have inserted far enough as the spring loaded door handle will pop open when free of the locking mechanism. Then just like a server hard drive tray you gently tug on the door handle and slide out the drive tray.



When the drive tray is free of the enclosure you then have to use a screwdriver to remove the long chrome post which helps protect the drive tray and keep it from getting deformed during insertion/removal of an empty drive tray. Once this simple task is accomplished one simply has to line up a hard drive inside the drive tray so the three screw holes on each side of the drive tray line up with their counterparts on the drive itself. Then you simply screw in the included screws to hard mount the drive to the drive tray.


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At this point of the installation you are ready to remount the now loaded drive tray back into the MobileSTOR enclosure. You should notice the long plastic runner located on each side of the drive tray, these runners have to line up with the keyed cut-outs in the enclosure’s sides or you will not be able to successfully mount the tray. It was found during testing that in order to make insertion as easy and smooth as possible one should hold the drive tray as perfectly parallel to the floor as possible; this greatly increases your chances of a successful insertion, while lowering friction. It is not that inserting a drive is difficult, but as with any new device, the drive tray runners are “sticky” and have not worn down with use. After about a dozen or two insertions and removal this stickiness went away and the process becomes smooth as silk.

To install the second hard drive (which is completely optional unless you want RAID capabilities) you simply follow the above steps again for the second drive tray. We would strongly recommend you do not throw away the chrome protection bars as they should always be reinserted when a hard drive is not being used in a given drive tray. When you have installed the hard drives the only things left to do is pick your RAID level and plug in the device. To chose your RAID level one simply needs to use a small flat nose screw driver and twist the recessed selector knob located on the back of the MobileSTOR. If you wish to use eSATA and your system is does not have eSATA capabilities you will need to install the included PCI bracket first, but this is fairly self explanatory and we will not go into any more detail than that.

If you have selected JBOD, or RAID 0 the installation is now complete and you will get the full capabilities of the device as soon as you turn it on for the first time. However, if you selected RAID 1 or SAFE33/SAFE 50 when you first turn on the device it will start to build its array. You will be able to use it right away but it will take a few hours for the array to be built and thus give you its full speed potential. During this time you will also not have any data redundancy so please be careful. In testing it was found that two 320GB hard drive took about 3.5 hours for the array to build. Your time may vary (depending on speed of drives used) but this should give you a rough idea of how fast it is.

At this point your MobileSTOR is now ready for action and unless you want too you do not need to install the included software. The included backup software is NTI Shadow copy and it is an extremely easy to use yet highly effective backup program. While it will not replace Acronis or Norton Ghost, this software should be all the average user needs or wants.


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To install NTI shadow copy, one simply inserts the included CD Rom and answers the questions the install wizard asks of you. If you are like us and you have “autoplay” disabled you may have to manually start the process but otherwise as soon as your computer recognizes the CD a window will pop up asking if you would like to install it and then where it should install the software. Once this painless procedure it done you are now the proud owner of a NTI Shadow Copy. As the name suggests, it will run in the background and as soon as you save a file to your hard drive it will automatically be saved the enclosure as well. Of course you can setup manual backups as well, but for the most part this easy to use piece of software will do it for you as long the enclosure is turned on and available. What more could you ask for from a free piece of software?
 
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Testing Methodology

Testing Methodology


Testing any external storage enclosure is not as simple as putting together a bunch of files, dragging them onto the arrays drive folder in Windows and using a stopwatch to time how long the transfer takes. Rather, there are factors such as read / write speed and data burst speed to take into account.

For these tests I used a combination of the ATTO Disk Benchmark, HDTach and the SIS Sandra Removable Storage benchmark for testing the USB connection.

For all testing a Gigabyte PA35-DS4 motherboard with its built in USB controller was used.

All tests were run 4 times and only best results are represented.

Processor: Q6600 @ 3.2GHZ
Motherboard: Gigabyte p35 DS4
Memory: 4GB G.Skill PC2-6400
Graphics card: XFX 7200gt 128mb
Hard Drives:
1x Western Digital Se16 320GB (computer)
2x Seagate 7200.10 320GB (for MobileSTOR)
Power Supply: Seasonic S12 600W
Case: CM 690

Alternative Enclosures used for Comparison and Contrast:

1) Mediasonic HUR1-SU2. For more information on this unit please read our review on them here: http://www.hardwarecanucks.com/foru...al-bay-raid-hard-drive-enclosures-review.html

2) Thermaltake BlacX. For more information on this unit please read our review on them here: http://www.hardwarecanucks.com/forum/hardware-canucks-reviews/5476-thermaltake-blacx-review.html

3) Icy Box. For more information on this unit please read our review on them here: http://www.hardwarecanucks.com/foru...icy-box-jbod-hard-drive-enclosure-review.html

4) Consus-M For more information on this unit please read our review on them here: http://www.hardwarecanucks.com/foru...ech-consus-m-hard-drive-enclosure-review.html
 
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AkG

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Performance Results

Performance Testing



Read Bandwidth

For this benchmark, HDTach was used. It shows the potential read speed which you are likely to experience with these enclosures.

read.jpg

With read speeds it appears the MobileSTOR’s burst performance is more or less handicapped by either the motherboard’s SATA controller or the SIL 5744 controller. Either way it does not really matter as what is really important is the average read speeds. In this area the eSATA connected MobileSTOR simply walks away from the rest of the competition. Even in JBOD performance it is better than the rest. However, as is becoming a reoccurring theme, the USB results are less than one would like to see, they are not abysmal but by the same token you certainly wouldn’t purchase this unit based of those numbers either.


Random Access Time

Once again, HDTach was used for this benchmark. This benchmark tests how quickly different areas of the drive’s memory can be accessed. A low number means that the drive space can be accessed quickly while a high number means that more time is taken trying to access different parts of the drive.

random.jpg

When it comes to random access times the MobileSTOR is very good to good with eSATA but only mediocre to sub optimal over USB. The latencies when using USB are large enough as to be noticeable. It is becoming very obvious the SIL’s forte is not USB performance; this is OK as its main job is eSATA which performs very well.


SIS Sandra

This test was run with the removable storage benchmark in Sandra XII Standard. All of the scores are calculated in operations per second and have been averaged out from the scores of 4 test runs.

sis.jpg

As we saw with the previous tests, the MobileSTOR is only a mediocre performer when in USB configuration. Oddly enough, only while in RAID 0 is the MobileSTOR a better SiS performer than the single drive Eagle Consus-M.
 
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AkG

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Performance Results pg.2

ATTO Disk Benchmark

The ATTO disk benchmark tests the drives read and write speeds using gradually larger size files. For these tests, the ATTO program was set to run from its smallest to largest value (.5KB to 8192KB) and the total length was set to 256MB. The test program then spits out an extrapolated performance figure in megabytes per second.

USB

san_digital_usb_JBOD.jpg
san_digital_usb_raid0.jpg

san_digital_usb_raid1.jpg
eagel_USB.jpg

MEDIASonic_atto.jpg
icy_box_atto.jpg

BlacX_ATTO.jpg


Even when compared to another eSATA based solutions, the MobileSTOR’s SIL5744 just is not a great USB performer. While 30MB/s read and 27MB/s write speeds are decent, they just cannot hold a candle to the performance of dedicated USB storage solutions. All in all this is to be expected as the USB connectivity is more of value added feature to be used only when absolutely necessary. After all, anyone who buys an eSATA capable device would be foolhardy to use the slower USB option unless they absolutely had to.


eSATA

san_digital_esata_JBOD.jpg
san_digital_esata_raid0.jpg

san_digital_esata_raid1.jpg
eagel_eSata.jpg


Here is where the rubber meets the road so to speak. Without a doubt, these numbers are extremely good. Even when in non RAID JBOD configuration this enclosure posts some great numbers, and the RAID 0 numbers are excellent for a two drive RAID array. The Sil 5744 may not be good at USB but at its main job it is a wonderful performer.


Extended Runtime Testing

Where these units are marketed towards the home environment, it is reasonable to expect them to be able to handle moderate usage, with random insertion and removal and random requests for data. To test how robust this unit is, and how well the active cooling would work, the MobileSTOR was subjected to a 3 Day torture session. During this time the hard drives were inserted and removed 40 times (and yes we did count the number), the RAID 1 array was instructed to do a hard format and was filled and emptied numerous times.

During this testing the mute button did come in handy as the temperature alarm did go off, and if it wasn’t for the mute option it probably would have driven us insane. On the positive side, after 3 days the Seagate 7200.10s, while getting warm, were not anywhere close to being in danger of overheating. Their removal and insertion actually got easier as time went by and unlike some enclosures we have tested in the past we would not hesitate to recommend you use and hard drives you wish (even if the hot running WD Raptor, or any other hot running hard drive) with this enclosure.
 
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Disaster Recovery

Disaster Recovery



Testing Methodology

While a RAID Hard Drive Enclosure should be easy to use and have decent performance there is one area where it absolutely has to be 100% reliable and that is with its ability to recover from a dead hard drive (aka Disaster Recovery). Unfortunately, in the real world things are rarely as black and white as this and nothing should be taken for granted; especially when precious records are on the line. Even more basic is that while yes an enclosure should always recover from a bad drive, but what about its rebuild times? The amount of time it takes for an Enclosure to rebuild its array is very critical, as this is a time where it is most vulnerable to catastrophic loss of data. This test can therefore be considered a three part test.

The first part is PASS/FAIL and deals with did the RAID array work, is the array’s data still available and not corrupt when a hard drive “dies”.

The second part deals with how the array deals with replacement of the missing hard drive and is also a PASS/FAIL in that does the array start rebuilding or will it crash / hang? Does it require you to rebuild the array manually by first destroying all data on the array and starting from scratch (which is in our opinion unacceptable performance).

The third part (should it pass the first two parts) deals with how long it took for the array to get out of degraded mode and is also a PASS/FAIL. Regardless of performance we will inform you how long it takes but if its rebuild performance is less than 50 gigabytes an hour it is not fast enough to be considered effective.

To this end for each mode that the Enclosure offers that has disaster recovery, we start by first formatting and then filling them to the maximum capacity available in a given mode. After this was completed and we then verified that the data was indeed stored on the Enclosure before simulating a catastrophic failure. This failure was accomplished by removing one of the hard drives, while the unit is running (if it supports hot swapping, if it does not we power off the unit and remove the hard drive and then turn the unit back on). We then checked to see if the data was still available. If it is we then replace the “dead” hard drive and observe what the unit does with it. As soon as the hard drive is reinserted we start the timer and keep it running until the Enclosure informs us that it has finished its rebuild. All tests were run twice. All tests were not performed “one after the other”; rather they took place over a period of a couple of days and were widely spaced out so as to help reduce any possible chances of overloading the array and introducing any non repeatable errors. If for any reason, the array fails a section of the test. The test will be reran, if it fails a second time it will be considered a true FAIL, we will however inform you of any errors we get during testing even if the error did not reoccur.


JBOD Mode

In JBOD mode the enclosure hard drives will show up as 2 separate drives under USB but only one drive will be seen and be usable when using eSATA. This is because you need a port multiplier (sold separately) for you computer to be able to see and access more than one array per eSATA/SATA cable.

When USB was used and one of the hard drives was removed the data on that hard drive was gone, but all data on the other hard drive was still available. Conversely, with eSATA it all depends on which hard drive you remove, if you remove the one your computer can not see it does not appear to matter, as all data is still available from the single JBOD drive. If you yank the hard drive that the computer does see, the other JBOD array instantly appears. This can be confusing as it gives no indication that it is a different array.

While using USB, if the “dead” hard drive was reinstalled in the MobileSTOR the hard drive was instantly recognized and all data was still intact. If however, we replaced the “dead” hard drive with a freshly formatted drive (or just reformatted the dead one) all data was lost.

While using eSATA, if the “dead” hard drive was reinserted that array would instantly take over for the second JBOD array as if it had never be missing! This to us will just compound your confusion if suddenly your “new” data disappears and your old presumed missing data suddenly reappears!

Please Note: This is a common trait that many dual bay eSATA enclosures share and is more the fault of the eSATA standard than that of the manufacturer. For this reason this wonky behavior can not and will not be held against any enclosure that exhibits it. If we ever test an enclosure that does not exhibit this behavior and in fact has a built in port multiplier we will make sure to highlight this for you.

Overall this is a FAIL for all tests, as in the real world a dead hard drive would destroy all data. If, however you remove a good hard drive you can rest assured that you can simply reinsert it and everything will be fine when you reinsert it.


RAID 0 (BIG & FAST)

Spanning Mode (AKA “BIG”): The two hard drives will show up as one large single double capacity drive and data is written sequentially filling one hard drive before starting to write to the second drive.

RAID 0 Striping Mode (AKA “FAST”): The two hard drives will show up as one large single double capacity drive and read/write performance will be increased. This is because the array controller splits each piece of data across both HDDs in segments.

For both of the RAID 0 modes the results were the same. When a hard drive was removed from the enclosure the entire array became inaccessible (even in disk management it was not accessible; rather an 8GB unknown partition showed up but you could not format it nor assign a letter to it). When the hard drive was reinserted the array was instantly recognized and all data was not only safe but was also accessible. If the removed hard drive was first formatted the enclosure would also know this and start to rebuild the array which was darn near instantaneous for both modes, of course if Striping mode is used ALL your data on that array is gone but that is what happens when a zero redundancy RIAD level, but at least the new array is quickly available so you can get on with your post hard drive crash life. For SPANNING mode the data on the original drive (hard drive we left alone) is still there just any data from the replaced drive is gone. Either way, with these two modes expect data loss and plan accordingly (i.e. don't store anything that you think is important).

Just as with JBOD this is a FAIL for all sections as a dead hard drive will kill all your data, but once again if you remove a good hard drive you can rest assured that you can simply reinsert it and everything will be fine when you reinsert it.


RAID 1

In RAID 1 the enclosure's hard drives showed as one single drive. Initial array build time was about 2 and half hours.

When one of the hard drives was removed all data was still secure. The only noticeable difference was that the Alert LED went on. If we reinserted the “dead” hard drive the MobileSTOR was smart enough to recognize it and realize that no rebuild was necessary (recognize / quick test phase was about 5 seconds). However if we formatted second drive before insertion the enclosure was even smart enough to know that it needed to rebuild the array which it did so almost immediately (once again after 5 or so seconds). Just as when first created the Array rebuild time took about 2.5 hours to complete. Overall, this is amazingly good performance for an enclosure in this price range and can be considered an easy PASS.


SAFE33 & SAFE50

SAFE33 mode creates a secure RAID 1 array using 33% of the drives’ capacity. The remaining storage will be transformed into a quick RAID 0 (FAST) array, which works perfectly for fast, temporary work storage. As with JBOD you need a port multiplier to see both arrays when using eSATA, as only one RAID will appear. It is always the RAID 1 array but this negates the speed advantage this hybrid RAID level offers. When using USB, both arrays do appear and are accessible. Regardless of connection type, initial build takes about thirty to forty minutes longer than RAID 1 does.

SAFE50 mode creates a secure RAID 1 array using 50% of the drives’ capacity. The remaining storage will be transformed into a quick RAID 0 (FAST) array, which works perfectly for fast, temporary work storage. As with JBOD you need a port multiplier to see both arrays when using eSATA, as only one RAID will appear. It is always the RAID 1 array but this does negate and speed advantage this hybrid RAID level offers. When using USB both arrays do appear and are accessible. Regardless of connection type, and as with SAFE33, initial build takes about thirty to forty minutes longer than RAID 1 does.

The results for both Safe33 or Safe50 are exactly the same. The only difference is the amount of storage space the RAID 1 array has. When a hard drive was removed from the enclosure under USB the RIAD 0 “drive” in Windows disappeared, however all data on the RAID 1 array was still accessible and except for the Alert LED on the front of the enclosure glowing there was no visible indication that anything had changed. When the drive was reinserted the RAID 0 array drive reappeared and all data was fine. The enclosure was smart enough to recognize it and did not instigate a rebuild of the array.

When eSATA was used the enclosure acted the same way except that the RAID 0 array was never visible (as discussed earlier a port multiplier is needed). Regardless of connection type used, if the “dead” hard drive was formatted before reinsertion the array would recognize that a hard drive was insert and begin its rebuild process. Just as the initial building of the array took about 3.5 hours to complete, so did the rebuilding process.

Overall you can consider this a PASS on three tests for the RAID 1 array and for RAID 0 it is a FAIL for all tests (with the same caveats given with JBOD and normal RAID 0).


Disaster Recovery Conclusions

When you take all this data and assimilate it as a whole a few things to tend to stand out. The first and biggest of these is the fact that this is a super fast enclosure when it comes to building arrays. Heck, approximately 150GB an hour for RAID 1 rebuild speed is downright amazing.

The next thing that stands out is that this enclosure is not just fast; it is smart too! With a lot of enclosures (even ones costing a heck of lot more than this one does) once a hard drive is pulled and the array goes into failure mode and the only way out of it is to rebuild the entire array from scratch. This is a long, tedious process that leaves your data vulnerable for hours; whereas this unit is smart enough to not only know when you reinsert the same hard drive back in but knows when the data is still there. This makes this enclosure extremely user friendly and a lot more attractive than its competition.

The only thing that does stand out that is less than optimal is the fact that SAFE33 and SAFE50 are very gimmicky in this specific implementation. If you are going to advertise the benefits of these hybrid arrays you should at the very least include any and all necessary equipment to get the most from them. As it stands those two Hybrid arrays are only practical when the customer uses a USB connection.
 
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