Introduction
The Sans Digital TowerRAID TR4M-B Enclosure is a Direct-Attached Storage (DAS) unit. A DAS unit refers to a device that is directly attached to a server or workstation, without a network in between. What this allows a WHS user, such as myself, to do is provide an opportunity to increase storage capacity beyond what is possible in the physical WHS computer. In my case, I have plenty of bays to add additional drives, but my motherboard supports only 4 SATA on-board devices. Using today’s 1TB drives, I would be nominally limited to 4TB’s of storage capacity. Using one of Sans Digital’s optional host adapters, it is possible to create an array of TR4M-B devices, which use port replication, to obtain a total WHS capacity of 20TB using a JBOD configuration. For those of you out there that must have the security of a RAID array, the Sans Digital device will allow you do this in a way that is transparent to WHS. Very nice!
So who is Sans Digital? From the Sans Digital website:
Sans Digital is a provider of high capacity, multi-functional advanced storage solutions. These storage units can be used in home offices, small and medium-sized businesses, video editing, data backup, surveillance systems and many other industries. Sans Digital’s products provide great solutions for companies and individuals across the world who need effective and reliable data storage systems.
Technology and Service Differentiation
Sans Digital offers storage products for RAID and bare-bone systems. With technologically advanced products, Sans Digital ensures that the products will meet the customers’ needs. By incorporating the latest technology, Sans Digital sets the standard in the storage industry.Product and Service Innovation
Sans Digital offers products and services that are exclusively unique, which help customers improve their productivity. With over 10 years of experience offering complete storage solutions, Sans Digital’s products have come to be distinct with their unmatched technology.Business Productivity Solutions
Every customer is different and Sans Digital recognizes that one size fits all storage solutions are unlikely to meet everyone’s requests. As a result, Sans Digital joined a wide variety of industry leaders to offer storage applications that are specific to various industries. This includes off-the-shelf or fully customized solutions.Audiences
Sans Digital’s main customers include business and enterprise, government and education, creative professionals, as well as consumer and SOHO, which are reached through our Distributors, System Integrators, Value-Added-Resellers, and Dealers.Sans Digital specializes in, but is not limited to, serving these vertical industries:
Audio-Video Editing, Data Backup, Surveillance Systems, Database Storage, Imaging, File Servers, and etc.
Specifications
Once again, from the Sans Digital website:
Overview
The TowerRAID TR4M-B is a compact RAID tower utilizing the latest SATA II port feature, where one single eSATA cable connects to four 3Gpps SATA II hard drives. Designed with easy installation in mind, the trayless TR4M-B allows instant installation by simply inserting the hard drives after opening the protective ventilating cover. It supports JBOD and Spanning modes for instant storage expansion. It also supports RAID 0, 1 0+1, 5, 5+spare via included software utility, for high performance and hard drive redundancy. The package includes a 2-port eSATA PCIe card at no additional cost, which allows the connection between two TR4M units (up to 8 hard drives) using only two cables. PCI/PCI-X options are also available.
Features
- Accesses four hard drives using only one cable.
- Host interface:
- eSATA with Port Multiplier.
- Supports RAID 0, 1, 10, 5, 5+ spare, spanning and JBOD using bundles software utilities.
- Drive interface: 4 x 3.5″ SATA I / SATA II Hard drive.
- Supports the latest 1TB Hard Drive. Up to 4TB in storage capacity.
- Supports Windows 2000, XP, Vista, and Windows Server 2003.
- Supports MAC and Linux. (Please note that the host adapter card is based on Silicon Image chipset, which currently only support up to MAC OS 10.5.1 by Silicon Image.)
Specifications
| Model | TR4M-B |
| Form Factor | Compact Tower |
| HDD Trays | 4 Hot-Swappable 3.5″ |
| RAID Level | RAID 0, 1, 10, 5, 5+spare, spanning and JBOD (using bundled utilities) |
| Maximum Capacity | 4TB |
| Auto Rebuilding | N/A |
| Hot-Spare | N/A |
| Host Interface & Transfer Rate | eSATA 3Gbps (via Port Multiplier) |
| Drive Interface | 4 x 3.5” SATA I/ SATA II |
| Cooling Fan | 3.15″ Ball Bearing Fan |
| Power Supply | 150W (120V-240V) |
| Control Interface | N/A |
| Status Indicators | Power LED and 4 * Access LED |
| Dimension (in) | 5.3″W x 7.1″H x 10.0″D |
| Weight (lb) | 5.9 |
| Safety Regulations | CE, FCC, UL |
| Limited Warranty | 1 Years |
| Package Contents | TR4M-B (1) Power Cord (1) eSATA Cable (1) 2-Port eSATA PCIe Adapter Card (1) Screws (1 set) Quick Installation Manual & CD (1) |
Available Models
| Model | TR4M-B | TR4M-B1T | TR4M-B2T | TR4M-B3T | TR4M-B4T |
| Hard Drive | No HDD | SATA II * 4 250GB | SATA II * 4 500GB | SATA II * 4 750GB | SATA II * 4 1TB |
| Total Storage Size | N/A | 1000GB = 1TB | 2000GB = 2TB | 3000GB = 3TB | 4000GB = 4TB |
Optional Accessories
- HA-SAN-4ESPCIX – PCI-X eSATA 4 Port Host Adapter
- Silicon Image SIL3124.
- Supports SATA II, up to 3.0Gb/s.
- Supports NCQ and LCQ.
- HA-DAT-4ESPCIE – Four eSTATA Ports PCI-Express (x8) Host Adapter
- Fully compliant with SATA I and SATA II.
- Supports Serial ATA Generation 2 transfer rate of 3.0 Gbps.
What’s In the Box
The TR4M-B|TR4M comes in a box with pictures of the main components inside, as well as as list a features, specifications and hardware connections on the various sides. The TR4M-B has the black enclosure while the TR4M has the silver enclosure. The box even includes a nice carrying handle.
When you open the box, the first item you will find inside is small placard that provides general contact information as well as technical contact information. This is a nice touch that should be the first item that any buyer should see with any consumer device. The box that you see first inside contains the ESATA card, DVD disk, and other accessories for the unit.
Burrowing down the past this box, you will find the the actual DAS enclosure and 4 small boxes tightly packaged around this enclosure. These boxes contain the physical hard drives. According to Sans Digital:
The hard drive bundles are not prepackaged at the factory to prevent hardware damage during shipment. They are all freshly installed and tested by our technical team. Once the testing has been completed, the hard drives are then taken out and packaged separately for the same reason. This is usually the case with units that require more than 2 hard drives, because with the weight of these drives, many things could go wrong during shipping. If the units come with hard drive trays, the hard drives are left within the trays when repackaged, so the customers simply need to plug the trays back into the unit. All of this is to ensure our customers receive thoroughly tested units, requiring as little installation as possible, so they could have the units up and running right away.
When you first see the unopened box, one must think that the TR4M-B is quite large. Looks can deceiving, however. The physical TR4M-B enclosure measures only 5.3″W x 7.1″H x 10.0″D. It is quite small and very unobtrusive. And did I mention that is has a very nice shiny black casing?
What is shown below are the items included in the accessory box. eSATA card, low profile bracket for the card, power cord, eSATA cable, DVD containing drivers and manuals, and a small bag containing the screws to attach the hard drives inside the enclosure.
The eSATA card and bracket are shown below after removal from their protective anti-static bag. The card itself contains 2 external eSATA ports. The chipset is a common Silicon Images SiI 3132 controller.
Installation
As stated by Sans Digital, installation of the hard drives is a relatively simple process. Remove 3 thumb screws from the back of enclosure, lift off the top cover, open the mesh front door, and slide in the drives. Secure the drives with the included thumb screws, reassemble the cover, and the unit is ready to hook up to your computer
One of the advertised features of the TR4M-B device is hot-swap capability. Installing the hard drives as indicated above eliminates this capability. I posed the question to Sans Digital regarding this installation procedure and their response was:
Our customers usually take advantage of the hotswap feature by simply sliding the hard drives into the unit from the front without taking off the top case. However, if the unit needs to be frequently moved around, we recommend the hard drive to be secured by screws to stop them from sliding out.
So, if one does not intend to move the unit after intial placement, all you need to do is open the front door and slide in the hard drives. One door, 4 hard drives. Simple hot-swap.
The picture below simply shows the inside layout of the enclosure prior to hard drive installation. You can see the backplane and just behind that is the 80mm exhaust fan.
This is shot of the back of the enclosure. Located on the back of the unit are the power connector and switch, power converter switch, exhaust fan, and eSATA port. The Sans Digital unit use Port Multiplier technology which requires just one eSATA connector between this unit and the host computer.
Just a couple of pictures of the TR4M-B unit sitting on top of my WHS CoolerMaster case. The enclosure finishes match perfectly! These 2 pictures give you and idea of the size of the unit. Very small and unobtrusive. If desired, you could easily stuff it out of the way in a corner. But why do that? It simply begs to be displayed up close and personal.
I reassembled the WHS computer and installed the drivers. I pointed the OS to the appropriate folder on the included DVD. WHS also checked the Microsoft web update for any updated drivers. In the end, driver installation was quite painless.
Once the drivers were installed, I simply plugged in the power cord and eSATA cable in the appropriate places. I had instant increased hard disk storage space! The following 2 pictures gives you a indication how the LED lights work. The lights on the right indicate power and the host indicator status. The 4 lights on the left indicate hard drive status. The second picture shows the change in disk status as a hard drive is being accessed.
And for those who like a nice LED fan, simply turn the enclosure around. The exhaust fan produces a nice soft blue hue from the LED’s. I can take or leave LED fans, but it is nice to be able to have an easy way to check for a correctly operating fan. And for you noise fanatics, of which I have to include myself, the fan is very quiet! I turned off all the noise producing devices in the area, with the exception of the Sans Digital unit. I could barely hear it from less than 3 feet away. I would call it a near-silent fan.
Total time to get this point? It is rather difficult for me to be definitive, as I was documenting all this as I went through the process. I would estimate that the total time from initial opening of the package to the point where I took the above pictures would be less than 30 minutes. At least for those that are at ease putting this this type of hardware together. It also depends on how much documentation you wish to read prior to getting the unit up and running.
Performance
Sam Wood makes a very nice add-in for WHS aptly named Windows Home Server Disk Management. With this nifty add-in, I was able to take a very definitive snapshot of WHS disk array, as can be seen below.
I clicked on the WHS Server Storage tab, which provided an alternate view of the storage array.
So, now for the real question. How does the Sans Digital device perform? Originally, I was going to use ATTO Disk Benchmark software, but it only recognizes logical drives, not physical drives. As I wanted to compare drives in my WHS array to the Sans Digital drives, I was forced to use the HD Tach Disk Bench software. While slightly outdated, it does recognize physical drives, which ATTO does not.
I first tested my WHS boot disk, which is a newer production model than any of the other drives. I also ran a test on a WD1600JS disk, which just so happens to be the same model as the drives Sans Digital sent me for this review. That was a nice coincidence. I ran my initial tests with the Sans Digital drives outside of the WHS drive pool. The following comparison chart shows my WD5000AAKS against the one of the Sans Digital WD1600JS drives. As expected, the later generation 500GB drive beat the 160GB drive easily. Of course, I expected this.
I than ran a test comparing my Seagate ST33206 320GB drive to Sans Digital WD1600JS. Once again, the newer generation drive easily beat the older generation drive. One item that surprised me somewhat is that the Seagate drive ate up CPU cycles. Must be one the reasons why these drives were selling so cheaply when I picked this one up.
Since I had a hard drive model of the same type in my WHS, a more fair test would be to compare these drives. The following picture provides this comparison. It was nice to see that the performance numbers were nearly identical. Whatever overhead that is required to attach this DAS unit to the host computer has minimal effect, if any, on performance. With the exception of Burst Speed which was considerably higher on the internal hard drive.
I emailed Sans Digital and asked them if they could provide some insight into this difference. Their response:
The Burst Speed is slightly delayed when the hard drive is in the unit because the data must be processed by the chipset of the Port-Multiplier feature. The Port Multiplier allows 4 hard drives to be accessed by one cable, and therefore the chipset scans all four connections when processing data (even if only 1 hard drive is present). While when the hard drive is in the computer, data is being accessed directly without going through additional chipsets.
Is Burst Speed important for a Windows Home Server? Possibly, but I doubt anyone would see a real difference in actual use. Regardless, I would rather have the single eSATA cable connection.
As a last benchmark, I simply compared 2 of the Sans Digital drives, just to make sure that they ran about the same. As can be seen below, the numbers were almost identical.
It was now time to add the Sans Digital drives the WHS array. I initially added these drives in a JBOD configuration.
I ran a test on one of the Sans Digital drives and compared it to the same drive when it was outside the WHS array. As can be seen, about the only item that changed was Random Access time. As this changed somewhat from test to test with various WD1600JS drives, I considered this to be a non-factor in real-life performance.
It was at this point that I decided to let the unit sit there in the array and do quietly do what hard drives do. Unfortunately, WHS’s drive balancing has changed significantly with PP1. I could probably let it sit there for a month or so without any data being put on. Most, if not all, of the data I have on my WHS is backed up in some form or another. As a result, I have never turned on folder duplication. It was about time to try out this feature, in an effort to make use of this increased storage capacity. As I turned on duplication of 500Gb’s worth of shared folder data, the transfer rate that can be seen in Windows Home Server Disk Management on the Sans Digital drives immediately took off like a rocket. It was quite interesting to watch the LED light show that the Sans Digital unit started to display. It kind of reminded me of a one of those display consoles in the original Star Trek episodes! The following picture shows how WHS spread Folder Duplication over the Sans Digital disk array.
One piece of technology that I have on my WHS is a Crystalfontz LCD display. I use this item to display several key performance factors of my WHS. While the folder duplication was occurring, I took some photos of a CFA-635 in action. What I saw was very little difference in CPU usage during this period. Most of the CPU usage that occurs on my WHS is from my BOINC program, which can be fairly CPU intensive. The CPU usage that I saw was in line with what I have seen in the past without heavy disk usage and/or without the Sans Digital unit.
Please note that I took the above pictures in a dimly lit room, so that the displays can actually be seen in the pictures.
It was now time to dismantle the JBOD setup and check out the RAID functionality of the TR4M-B unit. Setting up a RAID array is a relatively straightforward process. Simply insert the supplied DVD into your drive, locate (sataraid_utility folder) and execute the SATA install file. I used the Windows XP 2000 installer. The following pictures document the install process.
Once the RAID utility program has been installed, execute it and you are presented with the following screen.
Under the RAID Group menu, you will find the Create RAID Group item. Opening that brings you the following screen.
Select your RAID options and create your array.
The array I created is a RAID 5 array. If you look close, there is one item you may have noticed that created a problem for me the first time I created the array. You will notice a pull-down menu item: Capacity. The first time I went through this task, I did not scroll far enough down the menu. All I saw was 1GB, 2GB, etc. options. It is only at the bottom of the menu did I eventually find a “Max” option. I would suggest to Sans Digital that this option be the first item in the list, not the last.
Once I straightened out this anomaly, I went to Windows Computer Management, opened the Disk Management menu and prepared the disk for use in WHS.
Please note that I took these pictures before I realized that I had made the aforementioned disk capacity error. If done correctly, I promise that you get much better results!
Once I had successfully setup the RAID array and prepared it for use the operating system, it was time to see how it worked with the WHS Storage Array. If you set it up correctly, you will see the RAID array added instantly to the WHS Console Storage Array.
I followed the same procedure, using HD Tach, I had previously used by testing the Sans Digital drives outside the WHS and as part of the pool. The following picture compares the RAID array to one of the drives in the JBOD array.
The following picture compares the RAID array outside the the WHS drive pool and as part of it.
From the above pictures, one can come to 2 conclusions.
- As with a JBOD configuration, there is minimal difference between drive performance inside or outside of the WHS pool.
- There is a significant penalty for using a RAID 5 array. Both in performance and available drive space.
I do need to stress that the penalty for a RAID 5 array is not a Sans Digital problem. There are 4 basic types of RAID array available, RAID 0, RAID 1, RAID1+0, and RAID 5. RAID 5 provides the best balance of capacity, speed, and failure recovery. The key word is balance. In the end, I am happy to report that if you desire to use RAID in a WHS, it is rather painless to implement using the Sans Digital device.
Costs and Conclusion
The TR4M-B can be configured anywhere from the base unit without drives all the way up to (4) 1TB drives. One can spend anywhere from $295 to over $1200 for a fully loaded unit with the optional 4-port PCIe card. I took a quick look at Newegg to see what the street price of the base unit might be: approximately $225 shipped. That is a very nice price for what you get: a 4 HD enclosure, power supply, JBOD to RAID 5 capability, port replication, hotswap capability, and a PCIe eSATA adapter. The chart below provides you with the list price breakdown for the various versions.
| Model | TR4M-B | TR4M-B1T | TR4M-B2T | TR4M-B3T | TR4M-B4T |
| Cost | $295 | +$240 | +$360 | +$560 | +$800 |
| Optional PCIx 4-port Adapter | +$44 | +$44 | +$44 | +$44 | +$44 |
| Optional PCIe 4-port Adapter | +$154 | +$154 | +$154 | +$154 | +$154 |
With the cost of hard disks dropping on a weekly (or daily) basis, it would seem to be a little difficult to justify the cost of a fully configured case at this time. That is one area that manufacturers are at a disadvantage. They can’t/won’t adjust their Retail Price based on a fluctuating component market. Sans Digital’s response to this observation was:
Sans Digital uses Seagate or Western Digital for hard drive bundles. The pricing of the HDD bundles are slightly higher because they must be tested after the hard drives are installed, before they are released to customers. It benefits the end-users by saving them a lot of installation and setup time. One could also purchase the enclosures and install the hard drives himself.
One question that you may have regarding the TR4M-B device is what is the maximum storage capacity of the unit? What is noted below is my question to Sans Digital and their response.
If one purchases their own HD’s, is the maximum capacity 1TB per bay, or will these units accept the 1.5TB units that are coming on the market at this time?
Because the 1.5TB is not readily available, the compatibility is yet to be confirmed. We do not suspect there to be any problems because they are based on the same SATA technology. There was no compatibility issue when the HDDs went from 750GB to 1TB. The written specs will remain at 1TB, until the 1.5 has been tested and confirmed.
Pros
- Easy to setup. 0 maintenance after initial setup
- Direct Attached Storage is a perfect solution to increase storage capacity on a WHS
- Very reasonable price for the base unit
- High capacity four drive enclosure
- Trayless construction (my personal preference)
- RAID 0, 1, 10, 5, 5+spare, spanning and JBOD support
- hotswap capability
- Port replication requires just one eSATA connector
- Includes a 2-port PCIe eSATA card
- Extremely quiet
- Quality construction
- Small footprint
- Tool-less construction
Cons
- Can get rather expensive if one buys the unit with Hard Drives
- Port replication degrades Burst Speed performance
- Hotswap removal feature is for stationary units
Overall, I was very impressed with the Sans Digital TR4M-B DAS device. The pros noted above pretty much says it all. The cons that I noted are quite minor. Would I recommend it? Without hesitation. If you are out of SATA ports on your motherboard or out of storage bays in your case, this device should be on your short list of devices to consider to increase your storage capacity.
I would like to thank Sans Digital for sending me this sample for review.
24. February 2009 at 10:17 am
Using the TR5M eSata unit with HP Mediasmart HP470
I have seen many posts both here and on other sites in which people refer to using the Sans Digital TR5M eSata unit with an HP Mediasmart Home Server and have purchased a unit and installed a single 1TB drive.
No matter what way I manage the plugging in on the unti and the powering up of it and the Home Server, I cannot get the Home Server to see the attached tower and drive. Obviously, because the Home Server is an HP Mediasmart Server, there is no way to use the supplied sSata controller card.
So, my question is, can anyone out there tell me how they managed to get the Sans Digital unit to be recognised by their HP Home Server?
Thanks,
Patrick
24. February 2009 at 11:58 am
Hi,
Cancel my last post and question. After battling for days and reading everything I could find on the subject, I decided to try removing the hard drive from the Sans Digital device, removing it from the tray and then re-installing it.
While doing this, I noticed that the location of the drive, in the tray, was such that the drive connector was not reaching the backplane connector in the Sand Digital tower. I moved the drive further along the tray holder and remounted it. After starting the Sans Digital and then the HP media Smart Server, hey presto, I have another drive ready to add to the pool.
Boy, do I feel stupid.
Regards,
Patrick
13. March 2009 at 5:28 am
Hi Jim,
I bought one of these today and installed 4 500GB Seagate drives. Sans Digital is rather nebulous about what this unit really is (and they have no contact info at their website). It isn’t a hardware RAID unit like they imply, with a “free” eSATA interface. After wasting a lot of time on this (and I am a storage engineer), I figured out that the unit is merely a 1:4 SATA port multiplier. All of the work is done by the HBA. The SATARAID5 utility is configuring the HBA (not the box), and saving the config info in the HBA ROM. One clue to this true state of affairs is the enormous RAID level format time required to create 1 RAID-5 group (32KB chunk size) of the entire space – 9 hours! On a real multiport RAID card like my 4-port RocketRAID 2300, this same RAID level formating takes about 45 minutes.
If you configure the TowerRAID and create NTFS volumes on it, then move it to some other eSATA port, you will see the first disk in the unit and nothing else. (Standard SATA only allows 1 device per bus.) If you were expecting to use this unit as an external, self-contained RAID unit (like me), you will be rudely surprised when you attach it to another eSATA port on another HBA (or MB port) on the same or another system. Everything disappears, and you see an unformatted device (1 disk).
The Thermaltake MUSE R-DUO RAID (2 disk) is an example of a real, external, self-contained (entry level) RAID unit. The TowerRAID is best described as a JBOD disk cabinet with the addition of the Silicon Image 3726 Port Multiplier chip added (which only works in conjunction with the SI HBA providedby SD).
13. March 2009 at 6:16 pm
@Alan Benway -
Hmmm.. yeah.
The value to me is that it is a backplane 1 cable esata port multiplier that allows me to add 4 disks to my WHS storage pool. I guess you are right in that they do not make it obvious that the RAID setups require the sata card, therefore is not a fully portable storage unit (or self contained).
Wasn’t looking for that myself, was looking for exactly what I got. Using it with WHS as a way of adding additional storage space would preclude, I would think, detatching it and hooking it up to another server.
13. March 2009 at 6:26 pm
Maybe this will help you to understand what this is (DAS):
Entry-level DAS systems most often are made of an enclosure without active components such as controllers, thus access logic and fault tolerance patterns are provided by the server HBA.
I would hesitate to call myself a “storage engineer” although I work with storage on a daily basis, FC switches, Clariion, etc, however, I don’t expect a lot for around $170 when I purchase a DAS for home use. I expect what I got.
13. March 2009 at 7:43 pm
@Patrick Greene -
Since I am using the TowerRAID for external storage to my rather full PC tower (primary home office system), and it is merely a backup copy of some internal volumes, the shortcomings (other than being slow compared to the 2-disk Thermaltake MUSE Duo) can be overlooked. But this isn’t a DAS unit – that would mean that all disks are visible on any eSATA port on any host. The TR4M uses a specialized interface requiring the pairing of the SI HBA and the TR4M. At least it looks nice and is very quiet!
As a senior storage research/analysis engineer at a large enterprise storage manufacturer, I should be used to encountering marketing-speak instead of engineer-speak from a vendor.
BTW: The documentation (the SATARAID5 utility) at Silicon Image is far better than the version from Sans Digital. There is considerable design and functionality discussion of the various SI HBAs there as well.
I just wanted to post some comments here since this seems to be the only serious review of this unit (well done except for this one issue) on the web, likely to be read by others looking for such information. I wanted to help others avoid getting blindsided by the actual nature of this system.
14. March 2009 at 11:30 am
@Alan Benway -
I can understand where you are coming from; but again, you are confusing a mid to upper level DAS unit with a bottom of the line unit. Yes, more full featured (and much more expensive) Direct Attached Storage units can allow access from up to four severs – they can be accessed by multipule HBA’s, in fact, they have many of the same features as a SAN. But nobody (except you – it seems) is going to confuse this bottom of the line DAS for a top of the line unit.
You seem to make a big deal out of the fact the HBA must be paired with the unit to use raid – well, I have worked with SANs that HAVE TO USE an exact approved model of HBA. If I put in an unapproved HBA, I can’t see the LUN. So again, what is your point? That this unit isn’t a portable Thermaltake unit? Yes, we get it.
Here is probably what you wanted- LACIE 301355U 5TB Network Storage – cost $1,000. Has three SataII ports, gig E, USB. However, they don’t call it a DAS – they call it “network storage”.
Although the reach or capabilities of DAS have increased, the basic idea was it was “island” storage – hence directly attached – meaning directly attached to a server, you had to go through the host to get to it. I know that has expanded in the upper range, but again, this is a bare bones unit. I certainly don’t expect a KIA to keep up with my twin turboed 350Z, yet they are both automobiles. Perhaps in a few years the bottom of the line DAS units will have what you want. When you do discover a 4 drive DAS that has the features of a mid or high level DAS for under $200 please let me know so I can purchase a couple.
14. March 2009 at 11:36 am
I must disagree with you here. The definition you are using for Direct Attached Storage is not an industry definition. Perhaps you google it or whatever. You are much too narrow and confined in your thinking. As for SansDigital, yes, the documentation they provide is worse than bad – it is incorrect as many have posted here.
16. March 2009 at 2:54 pm
FYI, the base model is currently on sale at Newegg for $179. Other than the annoying blue light and the fact that the instructions are wrong about the drive order (it goes bottom to top!) this is a GREAT unit. I replaced my other no-name eSata enclosure that sounded like a wind tunnel with this and have never been happier.
18. March 2009 at 11:38 pm
@Patrick Greene -
Patrick,
1. My point in emphasizing the need for the included HBA was so others who read this same review (the only decent product summary out there) aren’t mislead by the statement that the HBA is optional. It is required unless you happen to have another SI 3232-based controller and it works with the TR4M (no guarantee).
2. I had not encountered the idea of a simple ‘port multiplier’ before. This entry level unit is thus even more entry level than I was lead to believe by the Sans Digital web site and the box labeling. This small learning experience made the $150 purchase (I bought it at a much better price than normal – it goes for $200 – 260 in Silicon Valley and the internet) more worthwhile to me, but maybe not so to others who are on a much tighter budget.
3. I have no misconceptions about the place in the world of these entry level (almost toy) units. I live in the world of state-of-the-art midrange and enterprise systems ( what we manufacture and sell). But with ASIC integration levels making the costs for small RAID arrays very low (as is the case with my MUSE RAID unit), I expected that the TR4M was indeed a stand-alone RAID box (with the expectation that it would have limited performance and maybe 1-2 years of use before it broke and was tossed out).
4. Sorry, but you are somewhat mixed up about what DAS means. It simply means Direct Attached Storage. Examples: internal disk on PC/workstation, internal disks on an internal RAID HBA; external disks in a JBOD cabinet (not what the TR4M is) attached to a port on a host; external disks in a semi-intelligent box (TR4M) attached to a host port; external RAID array attached over 1 or more host ports. The point about the port multiplier making the TR4M a non-DAS unit doesn’t work. Nearly every external array has intelligence that hides the physical disks and presents logical LUNs from RAID Groups to the host.
Also, a “storage island” describes all DAS storage, including the TR4M. In fact, most IT directors and CTOs will describe a commercial class midrange or enterprise array as “DAS attached” if there is no SAN involved. Usually this means unique attachment to a single host, but it could also be 8 servers direct attached (with 2 ports) to the 16 ports on a mid-sized midrange array used in isolation from other servers and arrays in a center. Each server uses different LUNS from the internal RAID Groups (of course), but it is still considered to be a DAS rollout by most.
5. I am well aware of DAS, SAN, NAS commercial-grade environments, especially the high-end (that is what I do 60 hours/week). The compatibility issue that you mentioned of host ports to SAN arrays is almost always the SAN switch at fault. It can also be an operating system patch problem, driver problem, or HBA design deficiency (one demised FC HBA vendor in particular). A NAS solution can be useful to both a home office (entry level) or a corporation (very costly, like BlueArc’s high performance units). Nearly all home-grade units are a joke, with major performance problems, reliability issues, and lack of CIFS support (Buffalo, Drobo, etc.). But they are easy to use and portable, if very slow.
New item: I have run into an annoying problem with the TR4M. I have run some tests and verified the problem. You cannot do a simple reboot of the WindowsXP host with the TR4M. The PC will never recognize. But the same is true of the MUSE box (on a different eSATA controller). One must power down the entire system, wait 15 seconds or so, then power up the TR4M and MUSE, then the PC a few seconds later. If you power up all 3 at the same time you have a 50% chance the TR4M HBA won’t see the TR4M box. On a simple reboot it will never work. Have you seen this?
19. March 2009 at 12:03 am
@Alan Benway -
I really don’t want to waste anymore space or time of the readers of this excellent review of a great low cost product on your ego trip about how you are right because you work with everything every day so you cannot be wrong. Whatever buddy.
I personally work with 4 EMC Clariion CX3-40s daily. Whatever and so what. Again, whatever. Like you said, this is a $170 “toy” next to the real stuff, and again, your point is you don’t get the features of the million dollar units? Whatever.
19. March 2009 at 2:13 am
@Patrick Greene -
No problem. Actually, I have no ego in this – I barely care except for the teaching aspect to help others avoid problems – what I do most of the time. I stopped being ego-centric way back when I passed 50. You apparently react with hostility when your view of the world is challenged (a classic sign of imprinting – not internalized knowledge). You threw up a scattered handful of what you thought were facts, but then didn’t like being challenged on your accumulted ideas – that is an ego-centric at play. So why are you so defensive when you encounter someone who has experience that is far above yours? That is a truism in everyday life. There are those who know more and have done more than I, and I am glad to chat with them since one can always learn new bits and pieces along the way.
I noticed you had no comment about the TR4M reboot issue, something useful for folks who might read this review.
BTW: Since you mention it, the CX3-40 is a good entry-level midrange box for an IT dept for edge solutions and such.
19. March 2009 at 2:28 am
Hi Jim
Say, I can’t make out the scales on the charts. I would recommend either saving these figures as higher res embedded images, or make them larger, or create a simple summary table of results.
In my backup tests (WinXP SP3, Explorer copies) from internal disks to the TR4M (in R-0 mode, 4 500gb7200RPM disks), I found that it could absorb about 38 MB/s on sustained writes (about 360GB and > 120k files and folders). Reads were about 45MB/s.
In R5 3+1 mode, I found that writes were about 12MB/s, and reads about 23 (same large copy workloads). R5 costs 4 disk IOs per host write, so no surprise there, except that the SI HBA doesn’t perform full stripe writes with heavy incoming workloads. But, for the money, probably shouldn’t expect that.
I would ask you to change the comment about the TR4M’s HBA – it is the guts of the TR4M and not a freebie eSATA interface for those who don’t already have one.
Thanks for putting together the review. It was helpful. Maybe add a comment to point folks to the much better documentation at the SiliconImage site.
19. March 2009 at 2:35 am
Hi Jim,
Disregard the comments about the chart sizes. Just noticed that they pop up when you click on them – duh.
19. March 2009 at 2:58 am
To Alan and Patrick: Regardless of who is right or wrong, both of you have provided some interesting points about the Sans Digital unit. Egos aside
, good stuff! Some of the points made probably go a little over my head, as I certainly do not consider myself a storage expert.
I will point out one thing. No where in my review do I indicate anything about hardware Raid. Everything at the beginning refers to software-based Raid. I would hope that most users/readers would understand that one is not going to get hardware Raid at this price point.
And FWIW, I did plug this directly from the original eSATA card to another one w/o a problem. Granted, it was another variation of a 3132 chip. From comments here and from Sans Digital, it also works with the HP MSS units. I would be curious to know what eSATA chip they use.
21. March 2009 at 7:45 pm
To all,
Thanks for the clarification on the SI chipset restrictions to use this device. My Express Card adapter has a 3132 chip, and the last comment suggests it should work. Going for it!
21. March 2009 at 10:36 pm
@Jim Clark -
Hi Jim,
I bought some extra hardware at the local FRYs yesterday to try an experiment. I added an internal 1TB Seagate drive and backed up everything on my 2 TowerRAID volumes to it to start with. I also bought an IOGear GICe702S3R5 2-port PCIe HBA which is also an SiI 3132 chip just like the rebranded SiI HBA included with the TR4M. I have 3 eSATA attached DAS units to experiment with: TR4M with 4 500GB HDDs, RAID-0 is one; the Termaltake MUSE R-Duo with 2 400GB HDDs, RAID-0 is the second; and a Vantec eSATA enclosure with 1 320GB HDD is the third (these run too hot after a few hours of moderate use for a work disk on my system).
I did have an SIIG PCI HBA with 2 eSATA ports (not an SiI 3132 ASIC) already in my main PC before I added the HBA from the TR4M. I had the MUSE and Vantec attached to that original HBA. Once I added the TR4M to the system, port-1 on the SIIG stopped working, and port-2 was eratic. Some sort of system conflict that I couldn’t find. Hence the removal of the SIIG HBA (it was just PCI anyway), and the installation of the new IOgear PCIe HBA ($30).
All 4 eSATA ports work reliably now, although I still must power up the TR4M unit about 5 seconds before the PC power, or the TR4M will not get picked up on the port scan (no green light, no disks visible).
As an experiment, I moved the TR4M to a port on the IOgear, and moved the other units over to the TR4M’s HBA. All units worked fine. I was wondering where the config info was kept for the RAID configurations, and evidently it is on the multi-port logic in the TR4M unit itself. I would have to install another IOgear HBA in a second PC here to verify that this is not captured in the Registry somewhere, but I doubt that is the case.
BTW: When I backed up the TR4M file systems to the new 1TB Seagate I timed the operations. The first volume on the TR4M contained 80.2GB of data (82,370 files, 6353 folders) and averaged 51MB/s (since this was a sequential operation). The second volume had a lot more very large Zip files (2-3 GB each), so the sequential efficiency was higher. That volume had 184.3GB (107,834 files, 10,887 folders) and it averaged 65MB/s. Hence, read performance out of the TR4M (in RAID-0)is very good, as is the write performance to the 1TB Seagate.
I haven’t had time yet to run multi-threaded IOmeter tests and conduct small block random tests (an IOPS measurement) to compare the 1TB Seagate with the TR4M and the MUSE boxes. As random (IOPS with a Response Time) and sequential (throughput as MB/s) workloads are at the opposite ends of the spectrum, a unit-unit-test can behave very differently. A sequential workload is the easiest test for any system controller, but it also shows up the back-end design limitations (larger arrays) as well.
BTW: At FRYs yesterday, there were 5 returned TR4M units on the shelf, and the sales dude who manages that section said those people couldn’t get more than one disk to work. So they were also tripped up on the nature of the box and required use of the 3132 controller.
21. March 2009 at 11:02 pm
@Alan Benway – Sounds you look have a pretty array of tools and understanding of how to test this kind of HW. Very nice!
It has been long enough that I do not remember some details: I had to return the drives, but they let me keep the enclosure. I had at one point 2 drives and later 3 drives in the unit. iirc, I had drives installed opposite (top down?) of what one responder indicated they needed to be. Worked fine.
Currently, it is not in use as I lost 3 drives in one day. 2 were in the Sans Digital and 1 in my computer. As a result, I have nothing ATM to test with.
I do not use RAID arrays much anymore, I’m more a JBOD user now, since is independent of having to match drive models. So I can not discuss much on that. In my review, it worked quite well, but it was of course 4 drives w/the provided controller.
When you say the Sans Digital works only 3132 controllers, I get the impression that this is RAID setups? If I am wrong there, correct me. Assuming that, what about JBOD/San Digital/non-3132 controllers? Go or no go?
26. March 2009 at 6:22 am
Because this enclosure uses a port multiplier your eSATA chip set must be “multiplier aware”, not all chip sets are. If you move to one that isn’t, it will only recognize the first drive, if any at all. The first gen HP MediaSmart servers use a different motherboard and chip set that are multiplier aware, so they will work with this box. However the new HP servers use an intel chip set that does not support multipliers and won’t work with them at all. I hope this clears up some of the confusion about it being a true DAS or not.
1. April 2009 at 5:39 pm
@Kevin Davis -
Kevin is correct. But there are only 3 eSATA chipsets out there (I had a list of their names but now I can’t find it) and only the SI seems to support the proper port-multiplier feature. Some motherboads have SI SATA controllers – don’t know if they would work using an eSATA finger connector plugged into a M/B SATA socket.
Anyway, I am having even more problems with the TR4M not coming up when the system boots. My method of powering up the eSATA units 10 seconds before the PC has stopped working for the TR4M. So far I can’t get it to work today (I only see the orange power LED, no Green host connect light once the bus scan detects the HBA). Since I have too much work lately to do I don’t have time to mess with it anymore. Going to replace it, and use the TR4M on another PC that rarely gets rebooted (security camera system controller and CIFS backups for the other 4 systems I have. I will send an email to tech@sansdigital to see if they have an answer (or even do answer).
18. August 2009 at 11:39 am
Thanks for your review. It helped me decide to try the Sans Digital TowerRAID with my Acer easyStore Home Server. It works flawlessly.
30. September 2009 at 9:16 am
I just ordered my third one, this one from newegg – $149, free shipping, and they included a Segate 1 TB 5900 RPM 'green' drive for free – that's a $79 drive on the site. I call them my 'mini' Clariions.