|Thecus N5550 NAS Network Storage Server|
|Reviews - Featured Reviews: Network|
|Written by Bruce Normann|
|Tuesday, 25 September 2012|
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Closer Look: Thecus N5550 NAS Server
The bottom line with any high performance storage solution is that the number of drive spindles in play is often more important than almost any other factor, assuming that everything else is based on reasonably modern technology. When you combine the higher level of performance with the greater flexibility for online RAID capacity expansion & online RAID level migration, the additional cost of the extra drive bays always looks like a bargain instead of conspicuous consumption. This is the reason more and more people are opting for NAS systems with at least four bays, even though they may not need all that capacity now. What initially looks like overkill in a NAS system might just be the very thing that saves the day some years down the road.
The Thecus N5550 is a relatively small unit, which is arranged in a tower format and should fit in anywhere, in a variety of home or business settings. The standard model is a diskless unit; Thecus doesn't sell them with drives installed, but there are a number of distributors that will bundle the NAS with some sensible drive combinations. The size and weight are a little smaller than the competition: 230mm (H) x 190mm (W) x 240mm (D), and 7.1 kg without drives installed. Each HDD you install will add about 1-1/2 pounds, depending on your choice of drive. Many users will be looking at 2TB and 3TB drives for a unit like this, and they're heavier than most. There are no handles on the unit, which can make it a bit difficult to pick the whole thing up once it's fully loaded. The top and side panels are metal, with a textured powder-coat finish, so they do provide some purchase for occasional transport.
We've all got data that we can't live without, the question is, how long do you want to be without it? Very few people are going to want to live without their important information for any length of time, and a RAID configuration that includes some redundancy is undoubtedly called for. With multiple SATA drives installed, you can have: RAID 0 (Disk Striping), RAID 1 (Disk Mirroring), RAID 5 (Block-level striping with distributed parity), RAID 6 (Block-level striping with redundant distributed parity), RAID 10 (Striped array whose segments are RAID 1 arrays), and JBOD (Linear Disk Volume). The most popular choice is going to be RAID 5 because it offers the highest capacity with built-in redundancy. RAID 6 offers additional redundancy, allowing for continued operation even with two simultaneous drive failures, and this option is available for the Thecus N5550. RAID 6 is very popular for larger NAS units and mission-critical data stores, because if one individual drive fails in a RAID 5 implementation, the array instantly starts operating as a RAID 0 configuration, which has NO redundancy. It stays in that vulnerable state until the array is rebuilt, which is a slow process that generally taxes the system and the remaining drives to the max, and can take several hours to complete.
Opening the plastic front door of the enclosure lets you access each of the five drive trays, with their locking handles. There are barrel locks on each of the handles, and two keys supplied in the accessory kit for them. My advice is to use the locks and think twice before unlocking the release lever. Trust me when I say that you do not want to start accidentally pulling drives out. The drive bays are not marked on the front bezel, the individual drive trays are not marked, and there was nothing in any documentation I could find that would identify Bay 1 v. Bay 5. Consequently, the first time I booted up the NAS and dug through the disk statistics in the web-based software, I found that I had a single drive installed in Bay 5. I'll tell you now (and for some number of months or years, this will be the only place you can find this information...), Drive Bay #1 is on top and Bay #5 is on the bottom. The LCD panel is providing useful information about the RAID system in the image below, and you can also see the backlit Power button, with its blue LED lighting up the universal on/off logo. The smaller button below it is the Reset switch. The four oval buttons below the display navigate through a number of system configuration settings. This is a relatively common feature on mid or high-end NAS products, but the Thecus N50550 goes way beyond this, with keyboard, video and mouse interfaces on the back panel that are fully functional for the normal user.
With the unit safely turned off, it's OK to remove one or more drives and they all slide out the front like this. Each steel-framed tray holds one individual drive in the N5550, and the tray is a common part across several models in the Thecus product line. The trays are not labeled with the chassis slot number. They are all physically identical and you can mix and match them all you want, until you build a drive array and then you had better remember which one goes where. I recommend making your own labels or marking the trays with a Sharpie as soon as you start installing drives into the unit; if you mix them up the NAS won't recognize the array, and worst case you could end up destroying data as you try to figure out which drive is which. Inserting and removing the drive trays was smooth and positive, both with HDDs mounted in the trays and without. The latches acted like a locking lever; once the trays reached the end of their travel, swinging the latch levers the tray firmly into place. It's a sturdy, well designed system for getting the drives in and out. Not that you want to take them out very often, maybe just for spring cleaning once a year!
Around the back of the Thecus N5550, you can see all of the hardwired I/O points. Starting at the top right is a trio of Audio jacks: Line In/Out and MIC In. Directly below them are a single eSATA connector and two USB 2.0 jacks, with an additional pair of USB 2.0 jacks below that. There are no USB 3.0 jacks on the back of the unit - they're all USB 2.0 spec, despite the different color coding for the two pairs. Still on the right side, about half way down are video connectors for VGA and HDMI, which can be used for system configuration in standalone mode, and as a regular computer monitor. Bottom right is where the two 1000BASE-T Ethernet jacks are located. Just to the left of that is the integrated power supply, with its own fan, IEC receptacle and power switch integrated into the rear panel. The main cooling fan is in the middle left, keeping both the drives and the electronics cool. I didn't see a spot for a Kensington lock hole.
There are ventilation holes on the sides, bottom, and rear of the Thecus N5550 chassis. The primary entry point for cool air is through the front of the drive trays; it passes over the HDDs and is then exhausted out the rear of the unit. The additional holes in the side panels help to balance the flow, especially if you let dust build up on the mesh front panel. I've yet to use a NAS that had effective filtering, but I guess the mesh on the front door does help catch some dust. In order to keep things cool when needed and quiet the rest of the time, the fan speed is modulated. I haven't paid much attention to fan noise in most of the smaller NAS models I've reviewed, as it was never really noticeable during my daily use. The Thecus N5550 continued that pattern, blending in to the background noise of my study, despite having two cooling fans exhausting out its rear panel.
The bottom of the Thecus N5550 is a simple affair with four composite feet, a few more ventilation holes to feed fresh air to the power supply, and a product label with Model and Serial numbers. All of the feet had slipped sideways a bit, as the adhesive holding them in place had loosened somehow. The unit was not subjected to any high heat conditions, but the power supply is located on the bottom, so maybe the heat was internally generated. The feet are pretty low profile, so there is normally not a lot of room below the bottom panel and I may have pushed the unit sideways when trying to lift it a couple times.
Now that we've had a thorough tour of the exterior, let's do a complete tear-down and see what the insides look like. The next section covers Insider Details.