|At a Glance|
|Product||Iomega UltraMax Pro Desktop Hard Drive (33744)|
|Summary||High-performance dual-drive DAS with RAID 0, 1 support and USB 2.0 and eSATA connection|
|Pros||• Easy to install
• > 100 MB/s RAID 0, eSATA writes
• Unhelpful front panel indicators
• Relatively high power consumption
• No monitor utility
• No RAID rebuild progress indicator
We generally have stuck to reviewing NASes when it comes to storage, in keeping with SmallNetBuilder's networking focus. But since there are not many sites reviewing attached storage and because it plays an important part in NAS storage expansion and backup, we are going to take a shot at adding it to SmallNetBuilder's coverage. First up is Iomega's UltraMax Pro Desktop Hard Drive (UMP).
The UMP is a dual-drive SATA-based NAS that attaches via USB 2.0 and eSATA or USB 2.0 and FireWire 400 / 800, depending on the model you choose. It comes in 1.5 and 2 TB capacities. But it appears that the 1.5 TB eSATA version is being phased out. Note that the USB / eSATA connection is either / or—you can't use both simultaneously.
Bill Meade actually wrote our first DAS (Direct-Attached Storage) review of the Norco DS-500 around two years ago. As I re-read it and compared it to the UMP, I was struck by the difference in ease-of-use between the two products. For example, some of Bill's review focused on his struggle to get the Norco's bundled PCI-X SATA adapter installed and running.
In contrast, the UMP will require no software installation for most users, as long as it is installed on a system that supports SATA drives. Even if your system doesn't have an external eSATA connector, you'll still be ok. All you need is an unused internal SATA port and the addition of an eSATA PCI bracket. You can also use a SATA to eSATA cable if you want to skip the bracket. Of course, if you choose the USB / FireWire 400/800 version, forget what I just said.
Figure 1 shows the rear of the USB / eSATA version that I requested for review.
Figure 1: Rear panel
Selection of individual drive, JBOD, RAID 0 and RAID 1 modes is done by setting three miniature switches and then pressing a recessed switch for about three seconds. The mode change took under 10 seconds, even for RAID 1. But I had to judge mode change completion mostly by listening for the hard drives to quiet down because the front panel indicators weren't very helpful. As Figure 2 notes, the bright white power light makes it difficult to see at least one of the disk activity indicators.
Figure 2: Indicator explanation
But it would also be helpful if Figure 2 provided an indication of each indicator's location and function, since the two indicator groups are not the same and there are no markings on the front panel to help. I understand that Iomega was going for a clean and elegant look for the UMP. But when form interferes with function, that's just poor design.
The UMP draws a surprisingly high 28W and there doesn't appear to be any idle drive spin down or other power saving mode. It is surprisingly noisy too, despite its lack of a fan. But the noise from the drives alone make the UMP noisier than some of the quad-drive NASes that I have used it with to test NAS backup performance.
I didn't take the UMP completely apart and didn't really have to. There isn't much inside, only two 750GB Seagate Barracuda 7200.10 (ST3750840AS) drives and a small circuit board, visible in Figure 3.
Figure 3: UltraMax Pro internal assembly view
The heard of the UMP is a Silicon Image Sil5744 Storage Processor (near the lower left corner of the board),which handles all RAID duties for both USB and eSATA connections. The USB / Firewire version uses a different device, which is probably not from Silicon Image, whose Storage Processor lineup doesn't include any FireWire models.
Once I set the volume configuration using the rear panel switches, I connected it to the Vista SP1-based NAS testbed system for formatting. Windows supports only NTFS formatting of volumes over 32 GB. But Iomega includes a FAT32 formatting utility if you want to use that most widely-supported format and can live with its 4 GB file size limit.
The Iomega FAT32 Formatter utility seemed to work ok to format RAID 0 and 1 volumes. You will need to use the Windows Disk Manager to create a RAW partition first, however. I found that the utility will even work with a NTFS-formatted volume, although you need to run it twice and ignore the format fail messages it will throw.
There really isn't much more to the set up. The Vista system had no problem recognizing the UMP when connected via either USB or eSATA. Iomega's documentation notes that eSATA is not plug-and-play like USB and recommends powering down both the host system and the UMP when connecting and disconnecting eSATA.
By the way, the HTML user manual that came on the UMPs included CD is out of date and lacking important information. So be sure to download the latest version from the Iomega support site.
With no admin interface and no monitor utility, it's up to you to interpret the indicator lights on the UMP's front panel to see what it is up to. This was a challenge when I performed a pull-a-drive test on a RAID 1 array.
Iomega's instructions emphasize that you must leave the UMP powered up when replacing a failed drive. So I started a long file copy, then pulled the top drive and waited to see what happened. Contrary to the Iomega manual, I did not see a red light to indicate a failed drive. Instead I saw a flashing green light in the top light group that started immediately after I pulled the drive.
Shortly after the drive was pulled, the file copy progress indicator stopped and I eventually had to kill the process. But I was able to access files on the UMP with the drive pulled out without a problem and also able to restart another file copy.
I then reinserted the top drive and the green indicator continued to blink. But the User Manual said that I should see a flashing blue light to indicate a RAID rebuild, which I never did see. The top green light continued to blink, even after I deleted all the files on the UMP and emptied the Recycle bin that is visible in the UMPs root directory.
I waited around 15 minutes and then shut down Vista and then powered off the UMP. Then I turned the UMP back on and booted Vista. Vista came up fine and showed the UMP both in My Computer and in the Windows Disk Utility. But the green light continued to flash, even with everything appearing to be ok. I think the light means that the RAID 1 array is still rebuilding, but have no way of knowing for sure, since there is no way to query the UMP to see where it is in the rebuild process. By the way, the light continued to flash until I shut down the system that it was attached to.
Performance - File Copy
Since we're just starting DAS coverage, I experimented a bit with a few performance measures. I tried our NAS iozone and Vista filecopy test tools and also tried HD Tune. I found that iozone, even when I used the -c switch, which in NAS across-the-network testing has the effect of removing higher-than-network-speed cached performance, provided results that were above both the 150 MB/s and 300 MB/s maximum transfer rates of 1.5 and 3.0 Gbps SATA connections until file sizes grew above 256 MBytes (Figure 4).
Figure 4: iozone performance
On the other hand, the Vista SP1 filecopy results were more realistic. Figure 5 is a summary of the write test results with the UMP configured in RAID 0 and 1 and with FAT32 and NTFS formatting. The USB 2.0 connection is clearly limiting the UMP's performance to the low 20 MB/s range. With a switch to the eSATA connection, write speeds jump to almost 108 MB/s for RAID 0, FAT 32 and 96 MB/s with RAID 0, NTFS.
Figure 5: Vista SP1 Filecopy write performance summary
The read test summary shown in Figure 6 again shows USB 2.0 connected performance in the 20 MB/s range, but slightly higher than write. The eSATA results are once more much higher, although only reaching a maximum of 83 MB/s for RAID 0, NTFS format.
Figure 6: Vista SP1 Filecopy read performance summary
These above results are all obtained with Windows drive write caching disabled because the Windows properties for the drive said that its write cache setting couldn't be modified (Figure 7). Each value is also the average of three filecopy runs.
Figure 7: Write caching can't be changed
Performance - HD Tune
This was my first experience with HD Tune, so forgive me if I err in interpreting its results. I started by running the Benchmark test, which runs on an unformatted drive partition, with the UMP in RAID 0 and 1 modes with an eSATA connection. I didn't bother testing with the USB 2.0 connection, since I know from the file copy results that it limits performance.
Figure 8 shows the result plot. The line trace represents write speed in MBytes per second, plotted across all sectors of the array. Since the outer sectors of a disk have a higher rotational velocity, we can assume that the test moves from the outer (0%) to inner (100%) to inner sectors. The average of 102.4 MB/s correlates pretty well with the 107.99 MB/s obtained with the Vista File copy.
Figure 8: HD Tune Benchmark - RAID 0 Write
Figure 9 displays the read benchmark results, which average around 81 MB/s. This is in the ballpark of the 75 and 83 MB/s readings for the file copy RAID 0 tests for FAT 32 and NTFS formats. More importantly, the lower read results correlate with the lower read results we found with the file copy test.
Figure 9: HD Tune Benchmark - RAID 0 Read
HD Tune also provides a File Benchmark test, which I also tried. This test writes and reads a test file of selectable size (I used 512 MB) using block sizes ranging from 0.5 KB to 8192 KB (x-axis). Figure 10 shows the results for a FAT32 formatted RAID 0 array. I'm not quite sure how to evaluate the results, since the block size used in file operations isn't something that is under user control. Peak performance is reached at the 128 KB block size and stays flat after that.
Figure 10: HD Tune File Benchmark - RAID 0, FAT32
Figures 11, 12 and 13 are the equivalents of the previous three plots, but with the UMP's two drives configured in RAID 1.
Figure 11: HD Tune Benchmark - RAID 1 Write
As expected, RAID 1 performance is lower than RAID 0. But the 61.7 MB/s average write correlates pretty well with the 62 and 63 MB/s measured via file copy. Read is also lower at 55.2 MB/s, but it again doesn't correlate as well with the 63 and 75 MB/s obtained with file copy.
Figure 12: HD Tune Benchmark - RAID 1 Read
The File Benchmark results for RAID 1 shown in Figure 13 show a different pattern from RAID 0. Performance continues to climb, although more slowly, after 64 KB block size, with read speeds even exceeding writes at some of the higher block sizes.
Figure 13: HD Tune File Benchmark - RAID 1, FAT32
My bottom line from all this is that I will probably use Vista SP1 file copy and HD Tune write and read benchmarks going forward and dispense with using iozone and HD Tune File Benchmark tests for DAS testing. Of course, I am interested in your thoughts on this.
This is my first DAS review, so my ability to compare the UltraMax Pro to other RAID DASes is limited. But I can say that it is easy to use with a SATA or eSATA equipped system—pretty much plug and play. It's also pretty fast if you like to live a bit dangerously and use it configured in RAID 0. But 50 to 60 MB/s RAID 1 performance isn't too bad either, if you opt for that safer mode.
The big downsides for the UMP are its relatively high power consumption, noise and cryptic front panel indicators that appear to be improperly documented. And while data seemed to survive the RAID 1 fail test, the lack of a RAID rebuild progress indicator and / or some sort of status monitor utility would make me feel a lot better.