Design and features
Thecus has carved quite the name for itself amongst network storage enthusiasts; however, of late it's faced stiff competition from the likes of QNAP and Synology, which offered similar performance and features, but with a much nicer looking chassis and interface. To this end, Thecus has released a new look firmware for its NAS, which is now rather AJAX heavy just like its competitors. The result is the inevitable increase in lagginess of the interface, but as a trade off the ease of use is significantly higher.
A five-bay NAS, the N5500 straddles the prosumer to SMB category. This in particular is highlighted by the presence of two Disk On Module (DOM) units, one containing the operating system, the second a mirror of the first, adding some redundancy for more demanding environments. There's still the power supply as a single point of failure, or potentially even the motherboard, but doing anything about that would likely drive costs up substantially.
Of course the usual iSCSI support is there too, and through USB it can act as a DAS too, offering a fairly large degree of flexibility. You can even choose the file system, a welcome addition, either going with EXT3, XFS or ZFS, although the latter would have to be run in user space to avoid licence issues, meaning performance wouldn't be too great. Not to mention it's there as a file system only — RAID-Z is not offered on the N5500, leaving the user with the choice of RAID 0, 1, 5, 6 or JBOD (and whether or not to encrypt those volumes). If you run out of space, you can stack multiple N5500s together using iSCSI to make it appear as a single storage unit to the outside world.
The dual-gigabit Ethernet ports support 802.3ad link aggregation, although as usual with Thecus we had fun navigating through it's not-so-intuitive LCD screen to manually set an IP to begin with — for some reason Thecus chooses to ship with DHCP disabled, a practice we wish it'd reverse. In setting the IP, we also noticed that the access door to the drive bays was a little flimsy and difficult to open via its magnetic-push latch.
Inside is an Intel Celeron 440, clocked at 1.86GHz and a 1GB DDR2-667 SODIMM, although there's a place for a second should you wish to upgrade. Expandability is decent too, with five USB ports and an eSATA port, should you need to attach additional storage to the unit temporarily. An RS232 port is supplied for UPS management, and if you're so inclined you can share a printer off one of the USB ports. All this seems to come at the cost of noise though, with the N5500 packing some relatively noisy fans to push the heat out.
Typically with NAS devices it seems those with the most features wins, and so the N5500 is stacked to the gills. On the server front, it can be an NTP server and a DHCP server, and also packs FTP, iTunes and UPnP media servers. For networking protocols it covers CIFS/SMB, NFS, AFP and Bonjour, and you can mount ISOs if you so desire. The usual email notification and wake on LAN is present, as is scheduled power on/off and disk spin downs for power management.
Active directory is supported, as is local user and group control. Thecus offers its unfortunately named Nsync for backups, although you're free to use whatever backup solution you like, so long as the NAS understands the protocol you're using.
Finally, the Thecus supports modules to expand capability — Thecus by default offers download manager, IPcam, web server and mySQL modules, although the community has long been developing its own modules for Thecus' range. While there doesn't seem to be any dedicated N5500 modules yet, no doubt some of the pre-existing ones will simply work off the bat.
Bugs and performance
Thecus' beta firmware (3.00.07) clearly isn't fully baked yet — which, given its beta status, is to be fully expected. In our testing, logging in as users other than anonymous caused the FTP server to hang when receiving passwords, and eventually claim the password was incorrect. We also found that you could not change the machine's workgroup without turning on ADS.
Thankfully, performance was fine. Copying across a 2GB file saw a maximum of 85MB/s read speeds from the NAS, while write speeds peaked out at 63MB/s. We would have preferred that the unit wasn't so noisy though — trapped in a server room it's fine, but given the Thecus effectively straddles from home user to small business, a quieter operation would have been a plus.
Thecus' N5500 is, like all of Thecus' lines, best suited to the professional user who doesn't mind tweaking the unit to get the most out of it. We believe QNAP and Synology currently have the edge in terms of ease of use, design and quietness, but the N5500 is not too far behind for those who know what they're doing.