Foreword
Yeah I’ve totally gone there; I’m actually including a foreword. I figured it was important to set the context of a
NAS build because understandably not everyone might understand what it entails.
The responsibilities of a NAS has become somewhat blurred over the years thanks to commercial offerings from the likes of QNAP, Netgear and Thecus ranging their NAS products from single bay disk enclosures to seven bay behemoths running a host of additional services like DAAP servers, bit torrent clients, UPnP streaming services and even databases.
This build focuses on some of the more traditional aspects of a NAS but using readily available components. The goal is to strike the balance between:
1) Upgradability
2) Performance
3) Power consumption
4) Physical size
5) Acoustics
This system should be able to perform on par, if not better than, the high end commercial NAS solutions. Obviously the cost will be slightly higher, as it often is when building your own systems, but just like other systems, we have full control over the machine.
A $1000 budget for such a system is fraction low in truth. I’ve not included storage drives that would be used in the RAID array - just like the commercial solutions. Sure you could probably match some of the goals for cheaper, you may even consider resurrecting that old Pentium 4 system you’ve got to make a cheap NAS, but I guarantee that you won’t meet all 5 goals I listed doing this.
Rusting’s Leviathan
Processor:
Intel Core i3-2100T @ $134.99
Motherboard:
ASRock H67M-ITX @ $86.99
RAM:
Corsair XMS 4GB DDR3 @ $39.99
Graphics Card: Onboard
Hard Drive:
Kingston SSDNow S100 16GB @ $51.99
Case:
Lian Li PC-Q08B @ $109.99
Power Supply:
Seasonic X series SS-400FL 400W @ $129.99
Cooling: Stock
DVD Burner: None
RAID:
Areca ARC-1220 @ $449.99
Total: $1,003.93 (I’ll give you the $4 mkay?)
Reasoning
I figured when constructing this it made little sense to just link to components without explaining why I selected them or what my criteria was. Hopefully below is helpful to someone.
RAID
The Areca 1220 card is somewhat pricey but is really the focus of this build. If the budget was slightly higher I'd go for the 1880 instead. This card has a good set of RAID options. You may want to replace the fan with something like a
Mini Zaze as the stock fan is almost certainly louder than 20db.
"A RAID card? It costs so much! Why don't you use a ZFS filesystem and ECC RAM? Why don't you just use software RAID?"
Personally I'd pay for the cost of improved performance and ease of configuration. It also means I can choose whatever OS I want to run on this rather than being forced to choose something that supports ZFS.
CPU
Several commercial high end NAS boxes opt for Dual Core or Atom processors. An i3 can idle at a lower wattage than Atom processors and whilst it will use more during operation it's processing power trumps the Atom. Those with dual core processors are using previous generations and do not benefit from the improved performance per watt. A regular i3 would fit the bill here. However I've taken it a step further by picking up a T model which has a TDP of 35W instead of 73W.
Some may argue that an i3 is a bit overpowered here especially when the RAID calculations are being done by the RAID card. My retort would be that given it's idling capabilities and the ambiguous use of NAS devices these days, it's a very flexible CPU for a NAS device.
Case
One of the fundamental problems with building a NAS is the case. In an ideal world NAS boxes are quiet, small and out of the way. It's the size of the case that is the biggest concern.
A small build will cost you more and will see you using specialist components rather than readily available components with competing manufacturers. Additionally a NAS with significant storage needs to actually be able to house all the drives which are rather likely to be 3.5" drives.
There are plenty of NAS cases out there but few support 6 with potential to cram more in there. The
Lian Li PC-Q08B does and it has USB3.0 slots and interestingly a 5.25 bay.
Why would you want a 5.25 bay? Well for a start you can throw in an optical drive in there and backup media directly on the NAS.
"But I can do that from a connecting machine?" I hear you spray at your monitor. Very true. How about a multi function panel with a variety of connectors that helps you directly transfer content to external devices? Still a bit boring. Let's up the ante.
How about streaming the contents of a Blu-Ray / HD DVD disc over the LAN to a machine that doesn't have these drives. Possible with clever use of a Blu-Ray/HD DVD combo drive and VLC. How about automatically backing up the contents of an audio disc to MP3 or perhaps even creating a convenient AVI / MKV version of a DVD you've put in the drive without even needing another machine to be on. Understand the benefit of a 5.25 bay in a NAS now?
PSU
I'm mad keen on using high end PSUs; they are the foundation of any computer system.
NAS machines should be designed with power consumption in mind as often they are on for long periods of time. A more power efficient PSU will help with this but it's very important to understand that these efficiency measurements are done at particular load percentages.
This system won’t have a particular high load on the PSU. A gold efficiency 400W does fit the bill well though. It’s difficult to find a gold rated ATX sized PSU for lower wattages.
HDD
I haven’t included storage hard drives in this configuration. With a variety of possible RAID configurations it’s hard to say what’s best to use. Most 2TB drives have the best capacity per dollar right now. Whatever you’d choose it’s best to diversify your drive selection. The probability of two drives failing at the same time from the same manufacturer from the same batch is far higher than completely different drives with the same capacity.
I’ve elected to use a SSD for the OS drive. Due to budget constraints I was forced to go for a lower capacity SSD. I would have preferred to use something that was 30GB or bigger. Here we are using the SSD for low power consumption and quiet operation; speed benefits are not our primary concern here but a helpful benefit.
If you configure the RAID card to idle the storage hard drives in the array where possible you’ll make significant power savings. This works even better if you ensure all your NAS services/servers are only using the RAID array when they really need to.
RAM
I’ve opted to go for a single 4GB stick of DDR3 RAM. This is plenty of RAM for a NAS; even arguably too much as the additional memory chips are being powered even if they aren’t being used by the system.
Others may choose ECC RAM over my selection and that’s entirely reasonable.
Motherboard
Solid little motherboard with USB3.0 support. Does what we need it to do. It would have been better if we had multiple gigabit ethernet connectors but you’d be hard pushed finding a readily available socket 1155 mITX board with this feature.