The Little Duck

The good:

• It's relatively cheap.
• Decent amount of storage.
• Plugs into ethernet.
• Web based management interface is strong.
• Reasonably quiet.
• Sleek looks.

The bad:

• It's quite slow.

This all started because one of the drives in my RAID1 array started dropping out. I felt I should take a full backup right away, but my existing backup drives did not have enough free space. I'm already running out of USB ports, and its always a hassle to hang the drive off a machine, so I decided to look for external drives with ethernet capabilities.

The Western Digital drive was the cheapest option that my five minute search turned up, and it was available at OfficeWorks near my work, so I went in and picked one up. I took it home and initially plugged it into the gigabit switch in my room while I got it set up. I skimmed the manual and it suggested that I install some windows software to help me setup the drive. That seemed like a lot of effort, so I just looked at the DHCP leases on my router, and navigated to the IP of the new entry in a browser. This took me to the login screen for the management interface.

At this point I hit my first snag, I had no idea what the default username/password combination would be. I tried the usual combos, admin/admin etc, and eventually got in. My first task was to rebuild the drive as RAID0, since I need all the space available on the drives. This was thankfully quite straightforward. My next task was to disable MioNet, and enable SSH + NFS, all of which was possible through the web interface, and no longer requires hacking the box. Again, all pretty simple stuff.

I mounted the NFS export on my Linux server, and I was away (slowly). I kicked off a backup of my home directories using DaR. I expected this to take about 350GB of disk space, and didn't have any firm idea of how long it would take. I left it running for a couple of hours, and was a little dismayed when I checked it before going to sleep and found it wasn't finished. This leads me to one of the good points about it, it's quiet enough to sleep while it is powered on. Unless the fan spins up. So I wake up the next morning and check on it's progress. Still going. At this point I'm starting to worry a bit that it's taking so long, but I head off to work.

So while I'm at work I start reading forums and reviews, and it seems that it is fairly well known that this NAS is quite slow. I am slightly comforted by how cheap it was. When I get home I find that it is finally done, and shut it down so I can move the NAS to it's final location. It's possible to sleep with this thing running, but it's not that fun. The new location runs off a 100Mbit switch, and after some problems on my end everything works out fine. I kick off a backup of my media and the system files, and resign myself to the backup taking a long time.

And take a long time it did. Five days since I purchased it, and the backups are done, 1.2TB space used. So its not really going to cut it if you need to make or restore your backups at line speed. I was interested in finding out exactly where the bottleneck was, so I ssh'ed into the box, and did some sequential reads and writes, getting about 35MB per second. Not great for RAID0, but much better than the 8MB per second I see over the network. At least we know the disks are not to blame. (They're 1GB WD Green drives i believe.) I ran 'top' while the backups we're going, and the cause became apparent. The nfs daemon sitting on 80% CPU usage. Since i also get the same speeds using SAMBA(cifs) I think I can rule out the implementations.

This leaves us with the real culprit, a weak CPU.

~ $ cat /proc/cpuinfo
Processor       : ARM926EJ-S rev 5 (v5l)
BogoMIPS        : 183.09
Features        : swp half thumb fastmult edsp java
CPU implementer : 0x41
CPU architecture: 5TEJ
CPU variant     : 0x0
CPU part        : 0x926
CPU revision    : 5
Cache type      : write-back
Cache clean     : cp15 c7 ops
Cache lockdown  : format C
Cache format    : Harvard
I size          : 32768
I assoc         : 4
I line length   : 32
I sets          : 256
D size          : 32768
D assoc         : 4
D line length   : 32
D sets          : 256

Hardware        : Oxsemi NAS
Revision        : 0000
Serial          : 00000b01fdad7040

It has 128MB of RAM, and it looks like most of it is being used for cache, although that may not help much in the case of full backups/restore.

The good bits...

It looks really sleek, and the front LEDs can be disabled. The management interface is nice. It would probably be fine as network storage for documents and bulk media. It supports all the protocols you might want to use, and has SSH access out of the box.