New NAS system

Afternoon all, I was very happy with the advice and guidance you gave me for my desktop build (still tweaking but should be my October project!). I still need to build a reliable NAS and an HTPC, this post is regarding the NAS.

I was going to just whack a load of old disks into an old desktop and run FreeNAS or something on there. But I'd rather build something specifically for the task. Below are the requirements and some thoughts on components. Any thoughts or recommendations are welcome.


The main uses for the NAS will be:
+ Media storage/streaming (HD video to XBMC etc., shouldn't require transcoding)
+ File/Backup storage

These are, for me, the important characteristics of the build:
+ Decent redundancy (RAIDZ2)
+ 24/7 availablity (although the option to schedule shutdown/WOL would be nice)
+ Low power consumption and low noise
+ Fast throughput to (potentially) multiple clients
+ Plenty of capacity (8TB+)

Motherboard/CPU/RAM
I've seen a few fanless motherboards with embedded Atom processors running between 1.6 and 2,0ghz. These seem ideal but also seem to have a lot of features that I won't need in a NAS (WiFi, Audio, GPU etc). There also seem to be about a million different versions of Atom chips available.

Ideally I'd like a basic board, with Gbit ethernet and 6+SATA ports for drives. Ideally, it would spin down the drives when not in use and maybe stagger the drive spin up on boot to avoid overwhelming the psu. Most of the atom board sI've seen only have 2 SATA ports, would I just need a PCI SATA card to add the extra ports?

I've seen boards with dual ethernet ports - would this make any difference to performance on my network? The house is fully Cat6 with Gigabit router and switches.

Note that I don't NEED it to be Atom based, happy to consider all alternatives if the price is good and can have fanless cooling.

RAM doesn't have to be spectacular, Ideally 4-8Gb and cheap.


Graphics/Audio
Basic on-board graphics that I can hook a screen up to for basic setup and diagnostics will be fine, but the machine will be run headless 99.99% of the time.

Storage
My current storage requirements are about 6-7TB. It'll increase gradually, but most of it is just media that I can move to optical storage once I'm bored of it. I see Amazon are doing WD Red 3TB drives for £104 delivered, designed for NAS and 3 yr warranty. http://www.amazon.co.uk/Western-Digi...dp/B008JJLW4M/ any thoughts on these?

I'd like some redundancy, RAIDZ1 seems to be optimal with 5 drives (1 for redundancy), giving me 12Tb of storage if I bought 3TB disks. If I went RAIDZ2 I would need to add an extra drive (6 appears to be optimal) giving the same storage but an extra disk for redundancy.


Chassis
This is just going to sit quietly in a room that is rarely used so doesn't have to look amazing. It'd be nice to be compact and have hotswap for 6 (or more?) disks. But hot swapping isn't important to me. Just something cheap and practical would be fine. I'll admit to not having done much research into NAS cases, so all suggestions welcome there.

OS
FreeNAS looks like it'll do everything I need. For free. I'll run it from a USB stick.

You seemed to have thought it through.

This keeps coming up, so when my DIY schedule calms down (soon I hope!) I will try and run some benchmarks for this sort of stuff. In the absence of hard data, here are my thoughts though:

1/ Atom is a bit gutless. In theory it should be able to drive gigabit speeds, but you want to handle stuff like raid parity calculations at the same time. Multi channel memory and a bit more grunt would be nice, as would the ability to plug in a ton of RAM should the prices drop again (I think many Atoms are still crippled to 2GB max).

2/ The hot air needs to be blown out by something. Unless you use the outside of the case as a heatsink (which is out of my budget, you don't say what yours is) then there needs to be a fan *somewhere*. Might as well put it on the CPU, the only component that really wants it.

I think the AMD FM2 platform is pretty good for this. The entry level dual core will flatten any Atom in CPU grunt, it can run 64 bit mode with lots of ram (specially if you pay more for a motherboard with 4 ram slots), the idle power is very good, and there are plenty of motherboards out there with 6 SATA slots on them.

The RED drives seem pretty good, I have a pair of 2TB drives in my home Linux server (which is socket FM1 for the reasons above). They are built to be low vibration and not lock up for ages if they get a sector error so that the RAID system can get on with its job of recovering the data. Even so, I think they are rated for use in a group of up to 4 drives? Best check on that in the data sheet. Cheap drives bolted together can generate some nasty harmonic vibrations and shake themselves apart, so although the RED drives are built with that in mind I would be thinking of how I can keep vibrations isolated in the design.

£32 CPU (A4-4000) http://www.scan.co.uk/products/amd-a...mhz-65w-retail
£66 for motherboard: http://www.scan.co.uk/products/asus-...hdmi-micro-atx

That motherboard is a tad expensive, but it has 4 rams slots, 7 internal 6GB/sec SATA ports + 1 e-sata and USB3. It also has a decent looking VRM which I like to see on a board I am going to want to trust for the next 5 years or so.

Edit to add: I doubt you will see real world performance improvements from bonding a pair of ethernet ports. There are cheap managed ethernet switches now that will support it, but it is extra expense and another thing to go wrong for only a doubling at best increase in performance so in a home environment I don't currently see it as worth it. Most of my machines at home are the other side of a wireless-n access point or a mains powerline adaptor, and they still work fine.

For hotswap I would be tempted to get something like this:

http://www.scan.co.uk/products/icybo...ckplane-module

Not tried that or one like it, for me it wasn't worth the money. If my home server dies, the family will have to contend with a half hour of downtime while I swap the drive over :D

I had provisioned a Zotac all in one board as a starting point: http://www.amazon.co.uk/ZOTAC-NM10-D.../dp/B003D3KASS which weighs in at more than your AMD suggestion, I'll definitely go for that as the extra grunt and RAM increase would be desirable for the parity work.

I also had a very brief look for a case and something like the Lian-Li PC-Q18B (cube style thing) seems good, that one in particular has 6x 3.5" internal bays. I wouldn't mind sticking a -quiet- fan in to this to move the heat. At just over a hundred quid I'd rather spend less on the case, but 6x 3.5" bays is a requirement.

I've gone for a Be Quiet 300W ATX12V / EPS12V PSU.

My budget is somewhat flexible, but I'd like to keep it around £800-850 if possible.


Edit: This motherboard is cheaper and seems to do pretty much the same, just removes a PCI slot and fancy Audio: http://www.scan.co.uk/products/msi-f...vi-d-micro-atx

Only 2 memory sockets, and the VRM doesn't look quite as beefy.

Are you in a hurry? The A88 chipset boards seem to be turning up with FM2+ socket, might stir the market up a bit.

Thanks Danceswithunix, sorry for the late reply. I'm not in that much of a hurry, was hoping to have something in place by Christmas to keep everyone quiet, but I can make do with my current setup if something good is looming. What advantages would the A88 chipsets bring?