BUILD Fanless bookshelf NAS

[lorchi]

Hi there,

I would appreciate if you could give me your opinion on my home NAS concept. I am a NAS newbie, tried to read a lot, but need a second view now.

Purpose:

• home office file server
• media server (database and file system operations only, no transcoding requirements yet, maybe more advanced in future with different CPU)
• auto cloud backup
• git server

Wishes / Requirements:

• silent
• low power
• small bookshelf size
• upgradable
  
• low maintenance
• quantity status quo: about 0.5 TB of critical data (private + office + R&D) + 0.6 TB of consumer media, expected to double within the next 2 years

Idea:

• using 2.5" notebook disks (upgrade to SSDs in a few years)
• passive (fanless) case
• put up a future-proof concept now, start with the JBOD that I own right now (2.5" HDDs: 512 GB + 640 GB + 1 TB + 2 TB), then upgrade iteratively (I don't expect the number of disks to exceed 4, I'd rather replace the smaller ones by new bigger ones) (correction: I had misspelled GB as MB before)
  
• spin down disks during long idle hours

Concept:

• Board: ASRock E3C236D2I
• CPU: Intel Celeron G3900T (best-priced low-TDP CPU with AES support)
• Case: Akasa Euler M w/ power supply (Smallest passive ITX case with support for 4x 2.5"-disks I could find. Next bigger one would be the Streacom FC5 EVO WS, which looks better for heat dissipation, but needs much more space.)
• RAM: 8 GB ECC (example)
  
• Boot drive: Mach Xtreme MXUB3SESU-16G USB SLC-NAND thumb drive (there is not enough space, I either need to find another USB key, or use an extension cable)

Main Questions:

1. Does my overall idea make sense, are things consistent (I know the space is somewhat tight, I plan to iteratively replace the drives)?
2. Any serious concerns about my JBOD for the moment? Should I rather go for same drives from the very beginning?

Further Questions:

• How does the minimum recommendation for the boot drive change if I want to put the .system folder onto it (thinking about spin-down)?
• What capacity can I go to with my JBOD now so that one drive can fail? About 1 TB I would guess, right?

Thank you very much in advance!

 

[Nick2253]

First off, if you configure your JBOD in any form of RAIDZ*, then all your drives will be treated as 512MB drives. If you put them in RAIDZ1, you'd get about 1.5GB. (I'm thinking you mean the smallest drive is 512GB, but that is the reality as you wrote it.)

The biggest problem reusing hard drives is that your drives are old and already used, which means their lifespan is unpredictable. Also, NAS loads are not the same as normal workloads, which is why we strongly recommend NAS drives. I doubt your four random drives are all NAS drives.

One concern that you might have with a fanless design is keeping the drives cool enough. When your disks start scrubbing, they will all build up a bunch of heat, which will be difficult for that case to dissipate. Instead of a fanless case, you might want one with a single, super-quiet fan, which could be spun up to handle higher heat loads when needed.

Another concern with those cases is they depend on odd form-factor PSUs. A good PSU is critical to the success of your NAS, where as a bad PSU could be its downfall. Additionally, it may be difficult for you to acquire a replacement PSU in the event it does fail.

I'm not sure what your exact size-footprint requirements are, and without knowing that, it's difficult to make other recommendations. That being said, I would recommend looking at a slightly larger case, like the Fractal Design Node 304. It's still a surprisingly small case, but it would let you use a standard PSU and 3.5" disks, which will save you money in the long run.

 

[ChriZ]

IMHO, critical data and JBOD don't mix together...
So I would forget about JBOD altogether and do as mentioned in the previous post: get new drives, even new non nas 2,5" drives will be better than the old ones (provided you burn them in properly before dropping data to them) make sure you have at least one super quiet fan to prevent them from reaching high temps, create a reduntant array with them, keep the old ones as a backup target and live happily ever after..

 

[lorchi]

Thank you very much for your reply.

I have misspelled the sizes above. The smallest drive is 512 GB (corrected now).

The unpredictable lifespan is indeed an issue. If I continue with my initial idea, I will not use old drives (at least according to their operating hours) and the availability of MTBF figures (some drives are old, some rather new).
I am aware that the loads differ, but I had forgotten about scrubbing. MTBF figures should enlighten the actual difference I hope. I am curious enough to try it out, maybe with increased redundancy. That's a useful link in your signature, Nick2253.

Proper burn-in testing is crucial, I can see that. Thanks for the reminder.

The PSU argument is valid, yet the competition for 12V pico-PSUs is getting better. I still have to look around.

I am hoping to find a case with a maximum depth of 300 mm. But that's still a pretty one you have mentioned.
I am fearing fan failure, and I hate noise. So I would need redundant, quiet fans. Usually notebook drives are designed for higher temperatures, if I'm not mistaken. I think with a good fanless case they should be fine.

[...] live happily ever after

Good point. Maybe my inclination to experimentation could be tamed bit more.

 

[Nick2253]

Be careful with MTBF numbers. MTBF should be used, at most, to compare reliability between hard drive models, and not as a measure of reliability of any one hard drive.

I don't think you need redundant fans. If you buy a high quality fan, I think it's unlikely that you'll experience fan failure. And, if you have your emails set up correctly, you'll learn of fan failure when: (1) your HDDs start overheating, or (2) you start hearing the fan. In either case, it would be simple to replace it then.

There is something to be said for notebook drives: they are designed to take more of a beating. However, much of that comes in the form of intelligent head parking and spindle stopping based on accelerometers, etc. I'm not sure if notebook drives are much better than 3.5" drives when it comes to the heat department.

 

[lorchi]

Meanwhile I took the heat argument serious. My selection above (the Akasa Euler M) is probably not a good choice for its internal disk stack and therefore the creation of a warmer spot.

I had another look at the Streacom FC5 WS EVO, which was tested here.

One advantage is that the drives are not stacked but layed out flat, compare this picture. So there won't be a hot spot.

Then I estimated the thermal resistance.
In the mentioned test, a temperature difference of 44 Kelvin was measured at about > 77.7 Watts (CPU under load (Prime95) with 65W TDP+ H61 chipset with 6.1W + 2x HDDs with 3.3W idle each) (comment about Intel TDP here).
With my proposed system (CPU 35W TDP + 6W chipset + 4x 2.5" HDD with 2.3W under load) the maximum load would be about 50W, which would result in 28 Kelvin delta T.

On a hot summer day I have 25°C at home, amounting to 53°C maximum system and HDD temperature, provided the case is not put into a locker (that's 127 Fahrenheit).

Sounds like just within regular HDD requirements. Edit: Provided this temperature is only reached say weekly during scrubbing, the lifespan might be okay.

Arguably, the amount of aluminum takes its toll on the environment.

Ps:
There is also a test of the Akasa Euler, which is a bit smaller than the aforementioned Euler M. With a 35W-CPU installed but no HDD (SSD only) it ran 8 - 9 Kelvin hotter than the Streacom FC5. Given the difference in size, the Euler M might reach 60°C under the above conditions.

 

[Nick2253]

53°C maximum system and HDD temperature

53C is crazy hot for a hard drive. Generally, you don't want your hard drives going over 40C. Sure, a hard drive is rated to work in that temperature, but running very long above 40C is going to shorten your hard drives' life real quick.

 

[lorchi]

You are right. I need to reconsider.

 

[nojohnny101]

I'm intrigued by what you're trying to do here.

I think you have gotten some good advice with the fractal node 304. Heat is solely going to tied to activity on the drives (since you said you're not going to be doing any transcoding or heavy taxing on the CPU). I would start with the node 304, get a very high quality fan (or 2), quality PSU, and then some 3.5"s. I think with that setup, you will not have to worry about heat. Your usage requirements for thr box are well within reason to having a small form factor and silent operation.

The node (turned sideways) fits your requirements of 300mm and will give good airflow. I had one before I upgraded to its larger brother (804). I had 4 X 2.5 in it (raidz2) and had 4-5 datasets there accessed maybe a couple of times daily and I also had plex on it. The c2550 (ASRock) was installed and I never had heat issues.

Since you are demanding the system be small, the components you pick could be under greater stresses so don't skimp.

 

[styno]

I can only recommend to have a look at the Noctua fans. After replacing all the case fans and swapping out the CPU fan, the only noise I hear are actually the hdd's. All that is in a Fractal Design 804.

If noise is such a big issue, go quality/low rpm fans, an excellent psu and without a doubt all-SSD. Never ever go fanless.

 

[lorchi]

Thank you for the encouragement :)
So I am trying to think bottom-up again.

Drive constraints:

• I really want it to be inaudible in a quiet reading room. That's my main motivation to go 2.5" (both noise and heat, whereas the latter converts into fans and volume).
• All-SSD is tempting but not affordable for me at the moment. If I go for 2.5" HDD now, I can do the move in a few years from now.
• Why shall I "never ever go fanless"? My struggles above aside, an all-SSD solution wouldn't require fans, would it?

Drive selection:

• My working definition of "inaudible": about max 25 dB in seek mode (single drive), better around 22 dB for drives in an array.
  
• I was not successful in finding any inaudible, 24/7-specced 3.5" drive. If there are any, please give me a hint.
  
• I continued to search for 2.5" drives. Regarding 24/7 operation I tried to initially filter by the availability of MTBF or related figures at all, as an indicator that a drive's reliability is taken care of. I found the following:
  • WD AV-25 WD10JUCT (76€ / 1TB)
  • WD Red WD10JFCX (70€ / 1TB)
  • Seagate Constellation 1TB (85$ in US, 180€ in Germany :-/ )
  • Seagate Enterprise Capacity (180€ / 1TB, 4Kn available (do I need this?), sorry the page only produces German results to me)

Housing:

• I have a new, serious idea: Separating the drives from the rest of the system, and re-evaluate the passive cooling options.
  • Mounting the drives on a natural convection heatsink:
    • A WDRed WD10JFCX emits 1.4 Watts at load. Directly mounting 4 of them on this heatsink (ambient convection provided) will produce a total delta T of 4 Kelvin at load.
  • ICYCube. Disadvantage: port replication.
  • A backplane cage mounted to the mentioned heatsink. The ICY Dock ToughArmor is full metal. Both together might make for a flexible passive cooling solution. But only a test could reveal the actual cooling performance.
• That creates a new possible vision for me: a DIY construction with thermally insulated split design and chimney effect.
  • How to do the mobo & CPU chamber?
    • Use the Akasa Euler M case? That would be money down the drain.
    • Use the mentioned heatsink and make a symmetrical case. I favor that. But how to connect the CPU to the sink? The Streacom HT4 thermal riser might make it, I hope it's high enough.

Time for an overall effort check......

 

[styno]

Why shall I "never ever go fanless"? My struggles above aside, an all-SSD solution wouldn't require fans, would it?

Now I feel bad for a short reply but I am on holiday typing from a phone ;)
Don't forget that there are more components besides of the disks that need cooling, you have CPU, voltage regulators and don't forget the memory that zfs will be more then happy to use. Ram sticks can and will get hot from time to time.
This being said, you don't need a typhoon in your case, but a small breeze just to remove some air from the hotspots could be more then enough. You can start with one or two oversized fans at low rpm and some extra heatsinks on components that are known to get hot. If the motherboard can regulate those fans in times of need you'll have a safety net in case things heat up unexpectedly.
Oh, and you have to fight vibrations, so proper mounting of fans and hdd's is a must...

 

[Dice]

I'll offer some comments and suggestions of what I believe is the appropriate road forward granted can be read between the lines of your request.

Get Asrock-c2550d4i.
It idles with ridiculously low power consumption, and features ECC.
It may appear expensive, but granted you get CPU/ITX/loads of SATA ports for the cost, it is still a valid route I'd say.

You will probably not need more than 16GB RAM.

For drives - I'd suggest you kill your laptop-hdd-darling as soon (and as violently) as possible.
Go for SSDs. I'm willing to argue that the success of the project relies on your willingness to sink enough money to get SSDs from the get go. Before that - Save, and DO NOT spend cash on laptop drives that delay your project further. Utter waste.
If this is worth doing - you should really not get stuck in a middle ground with a bunch of laptop drives - while dreaming of SSDs.

Buildwise -
I like the idea of chimney effects. At the moment I'm doing that myself in a router setup. Works lovely. However, there is a fan that is programmed to 'come in handy' when the load gets tougher.
If you'll get a real quiet PWM controlled fan and mount it as 'vibration isolated as possible', it will be virtually inaudible. On low RPM's, the fan vibrations are a far bigger problem than motor noise. Beyond this, you'd want to have as little air pressure resistance on both sides of the fan. That implies, having nothing blocking the intake and as large of an area for 'passive exhaust' as possible in the case.

Now for the nonsensical dreaming about pushing envelops in ways they probably should not be pushed:
- You could arrange a piece of metal, like an aluminum bar, that could be glued with thermal adhesive paste to the laptop drives, uniting them into one larger CPU cooler, such as the cheap EVO 212. It would be one hell of a Frankenstein move, and probably - sink more cash into doing the build than it would be to get a proper SSD solution from the beginning.

During all circumstances, I'd advocate some sort of fan installed, to get circulation in the case, at least occasionally. <ANY> forced air displacement is a FAR improvement over pure chimney/convection solutions relying on passive airflow. I've tried in numerous situations.

 

[Robert Trevellyan]

I have a suggestion that totally fails your size requirement, but is very quiet: Dell PowerEdge T20. I have one, and when I shut it down, I notice a reduction in ambient noise, but when it's running, the only thing I notice is drive activity, which I would expect to be inaudible with 2.5" drives.

(2.5" HDDs: 512 GB + 640 GB + 1 TB + 2 TB), then upgrade iteratively

To facilitate iterative upgrade, you could do striped mirrors: 512GB + 640GB in one vdev, 1TB + 2TB in the other. Initial capacity would be based on the smaller drive in each vdev, but would auto-expand when those were replaced. This would be much safer than JBOD.

 

[Nick2253]

As @Robert Trevellyan so aptly points out, "noise" is more than just a decibel reading. Psychoacoustics is the fascinating study of how we perceive noise, which is much more important in this case. Adding five or six decibels of white* noise to a room will only be perceptible if you directly compare the room with and without the noise. On the other hand, adding a continuous tone will be highly perceptible, even if it's just a hair above ambient noise.

(*Technically, a fan is going to produce something that is much closer to pink noise, but "white noise" is the more commonly understood figure of speech for that kind of noise.)

Some fan manufacturers have put in a lot of work to create fans that are perceived as silent. Noctua is probably the largest manufacturer that springs to mind, but there are many others. Personally, I have 9 Nidec Gentle Typhoon fans in my main gaming PC, and at the right RPMs, I literally cannot perceive that it's running, and they keep my computer perfectly cool.

Obviously, perception is subjective, so what works for me may not work for you. That said, don't discount the ability for the right fan(s) to produce a noise that works in your environment.

 

[Dice]

@Nick2253 provides great points on noise levels. I'd like to add some points on the topic of vibrations.
Vibrations generated by fans and hard drives are a completely different beast to cope with compared to pink noise generators. In comparison, pink noise types do not possess enough energy to cause materials to resonance behavior of coupled surfaces. Therefore, they can be easily dealt with by isolation in space. That is, basically put an air sealed, decently rigid box on top of the sound emitting source and you're done. Or at least, make sure the sound needs to bounce of absorptive materials as many times as possible before hitting your ear.
Vibrations from hard drives or fans are not as easy to cope with. This is due to they typically possess enough energy to make surrounding materials vibrate too, in resonance. Which - basically amplifies the noise by <a lot>. In your case - the case, the bookshelf itself can become the 'speaker box' for your little fans and hard drives.
Well you've guessed where I'm going already. In principal - remove as many moving components from the system as possible, and isolate their vibrations to not get acoustically coupled. In your case, no HDDs at all, a high quality FAN, sitting on soft dampening surface - without screws or anything that <couples the fan> to the "speaker box".
Even low quality fans, on low rpm, properly mounted without acoustic coupling to the mount surface can be virtually inaudible but move adequate amounts of air.

 

[lorchi]

Oh dear, you're all giving me food for thought. Good ;-)

@ tyno:

Now I feel bad for a short reply but I am on holiday typing from a phone

Then I wish you by heart that you can enjoy your holiday and take care of yourself and your beloved ones!!

To have a fan "just in case" (what most of you highlighted) sounds reasonable. I would like to see whether any mobo can actually have a fan standing still and only switching it on above a threshold.

@ Dice:

I'd suggest you kill your laptop-hdd-darling as soon (and as violently) as possible.

Wow. You're confronting me. Are SSDs more heat tolerant? If so, I could save the effort of thermal decoupling.

Thanks for the info about noise. That's actually within my knowledge. I used db(A) numbers here in comparison to my personal experiences with HDDs. The last PC I built was for my mom, used a dampened case, and had three super-silent 120mm-fans, and SSD and a notebook HDD. It's only audible when getting the ear about 20 cm close to it. For a DIY case I am considering wood for its dampening features (among optics) and likely some EM shielding.

But I have to admit that I am intrigued by the idea of creating a fanless thing. I am an engineer and I like challenges.

So why not remove everything that isn't necessary? In my light use case, it must be doable. Meanwhile I have found different reports of people stating that their natural convection systems remain dust free, precisely because there is no forced air movement (so the dust keeps floating out).

As a rough figure and using the formula from the Wikipedia article on the stack effect, it should be possible to get 2 - 4 liters / second airflow through the case via natural convection already at a dT of 20 Kelvin.

The HDDs can be mounted separately on a flat heatsink, whose airflow would merge with the main one at the exhaust, thereby being sucked out (if the main one is tapered). Dito the PSU.

I might sound crazy, but I'm drawn to try it using cardboard and light bulbs. Stay tuned ;-)

 

[Robert Trevellyan]

cardboard and light bulbs

You obviously haven't read the hardware recommendations sticky.
;)

 

[lorchi]

You obviously haven't read the hardware recommendations sticky.
;)

Uuuh, you got me. Caught up.

But I have expressed myself poorly. I would like to experiment with the chimney concept, and try it with cardboard models before building the actual system.

 

[Robert Trevellyan]

I have expressed myself poorly

Not at all, just my attempt at humor.