The Live Duo was tested with 02.30.19-277 firmware using our standard NAS test process. Tests were run in both Span and RAID 1 modes and are included in the benchmark summary for the Live Duo shown in Figure 9.
Figure 9: My Book Live Duo Benchmark summary
Windows File Copy writes measured 41 MB/s for span mode and a slightly-lower 35 MB/s for RAID 1. The same pattern was followed in the read results, yielding 63 MB/s for span and 40 MB/s for RAID 1.
Intel NASPT File Copy write was significantly lower for both span and RAID 1, coming in at 26 MB/s and 24 MB/s respectively. Read results were a bit mixed—65 MB/s for span (about the same as Windows File copy) and 54 MB/s for RAID1 (about 10 MB/s higher).
To see how the Live Duo fares against other dual-drive NASes, check the RAID 1 Write (Figure 10) and Read (Figure 11) File copy charts. The only other Applied Micro-powered NAS is the single-drive Live, which isn't shown. But the Live Duo's RAID 1 write performance compares most closely to Buffalo's LinkStation Pro Duo LS-WVL, which is powered by a 1.6 GHz Marvell 88F6282 Kirkwood SoC.
Figure 8: My Book Live Duo File Copy performance comparison - R1 write
Figure 9: My Book Live Duo File Copy performance comparison - R1 read
If you're interested in how single drive Live compares to the Duo, file copy writes (span mode for the Duo) are close at 43 and 41 MB/s and further apart at 78 and 63 MB/s for the Live and Live Duo, respectively.
Use the NAS Charts to further explore performance.
Drive Pull Test
As is our practice with new NASes, I performed a drive pull test on the Live Duo in RAID 1 configuration. Note that the default Span mode offers no data protection; if a drive fails you lose the volume.
I started a large folder file copy, let it run for awhile, then pulled the A drive. The file copy paused almost immediately for about 40 seconds then resumed. The first fail indicator was the tiny front panel light blinking yellow. Upon logging into the admin interface, the indications in Figure 10 appeared.
Figure 10: Login drive fail indicators
Browsing to the storage page revealed additional failure indications shown in Figure 11. And finally, an alert email arrived a few minutes after the drive was pulled.
Figure 11: Internal Storage page drive fail indicators
For recovery, as per instructions in the user manual, I first powered down the NAS, reinserted the drive, then powered back up. When I logged in after boot was complete, I found my data intact. But there was confusing information presented in the user interface. The little icon in the lower left of the admin screen had a green halo, but showed Status:Bad. Navigating to the Internal Storage page shown in Figure 10 still showed Drive A as failed and there was no alert / event shown at the top of the page.
But after a few minutes of revisiting the drive storage and home pages, I returned to the Internal Storage page and found Status had changed to Good. But the front panel light was still blinking yellow. A reboot eventually caused the little icon to change to Status:Good. But despite a complete shutdown, including a power cable pull, I was not able to get the front panel light to stop blinking. I also never received any indication via email alert that recovery had finished or even started.
So the good news is that it looks like automatic recovery ran ok. But given the confusing indicators, the average consumer will be in for a scary ride when a drive goes bad. Looks like WD has some work to do here.
If you like the features and price of the single-drive My Book Live, you'll like the Duo even more. In addition to a second drive that brings either more capacity in span mode or a bit more piece of mind with RAID 1 mirroring (which is no substitute for backup), you get whole-NAS backups to either an attached USB drive or any networked share. And the much-improved WD2go cloud-based remote access [reviewed here] is a nice plus, which is also available on the original Live via firmware update.
As usual, WD is aggressive on price, beating the comparable 4 TB Buffalo LinkStation Pro Duo by about $60. So in all, the WD My Book Live Duo is sure to provide attractively-priced, midrange performance networked storage with easy-to-use remote access for many value-focused buyers.