Low Power NAS Design

TrueNAS General
1

I’ve been using Free / TrueNAS at home for close to a decade, and love it. I’m going to build a low power server for my off-grid cabin that runs strictly on solar. By my estimate, I have a spare daily wattage of about 500w. In that, I need to run a server, a Verizon router, camera and POE injector (may need to switch to a rechargeable camera).

Power Requirements:
Verizon Router = 10w/hr = ~250w/day
Server ~ 10w/hr = 250w/day

This is a tight fit, and I’ve been wracking my brain trying to figure out the best configuration for my needs. What are my needs? I’m going to do remote backups of my home server to this secondary location - pretty minimal. I also run Zoneminder and want to monitor one camera 24/7. I’ll start with one camera, but could possibly go as high as three. My reading indicates that ZM needs 1 core / 2 cameras, and 2gb / camera. But it doesn’t really say what kind of processing power those cores need. For that, my best estimate is Passmark scores. My current server has a score of about 9,000, and I’m running six cameras, 8 jails and 3 VMs at around 40% cpu. I can obviously get away with less, but how much less?

I’m looking at Atom C3000 processors, as they’ve got lower power requirements. While a 2-core might squeak by, the 4-core models add significant piece of mind for only slightly more power. But how much (processing) power do I need?
The C3508 is 1.6ghz, uses 11.5w, and gets a Passmark score of 1,796
The C3538 is 2.1ghz, has a 15w TDP, and gets a 1,889 Passmark score.
Both of those already push my power budget. Is either of those enough, or should I start looking at 8-cores with Passmark scores above 4,000?

Am I barking up the right tree? Is there a more power-efficient processor family that can handle an idle server and a constant security camera feed, and remain within my 10w/hr budget? I still haven’t added discs, so will lean heavily toward M.2 and SSD.
I love SuperMicro boards, and am looking at models in the A2SDi family, but I’m all ears.

2

You have not stated the capacity you require, that will be important. And while NVMe m.2 are nice, one of the CONs is replacement. It gets more involved replacing an m.2 card, not a great deal however it is not as simple as swapping out a SSD.

But capacity and redundance will play a big role in this design.

As for the MB and CPU, an Atom setup would be good, however you need to see what your other programs require. A fanless design would be ideal, if you can do it. That doesn’t mean you can shove everything into a really small case.

With respect to a power supply, a PICO power supply has been talked about for providing very good minimal power waste.

2 Likes
3

When you’re unsay 500w you mean 20Wh.

1 Like
4

Yes, 20wh available, and the router uses 10wh (verified with a meter plug).

As for capacity, I’d probably want 4-5TB for backup, another drive with ~2tb for the camera, and redundant boot drives. A motherboard with two M.2 slots and four SATA ports would be ideal.
I agree about the fanless design, and the Atom X series has processors designed to operate on 6w at 85 celcius (Atom x7211RE). I’d like to aim for a 4x hot swap mini-ITX chassis like the Supermicro CSE-721TQ-350B2, although there are similar designs for 1/4 the price sold on Amazon by “KCMconmey.”
There’s a very interesting Power/Performance list on Passmark that also points at some i7 cpus capable of 9w TDP and over 13,000 Passmark score.

Thanks for joining to discuss.

5

It looks like I can buy the SuperServer 5029AP-TN2 for around $550 - 4 atom cores, 9w, plus enough expansion for all of my drives.

6

20Wh is a…small amount. You will see greater variations due to weather and length of day. I’m not sure the basics premise is sound tbh.

What’s the solar system and battery storage like?

7

I seriously doubt you are being realistic. The 5029AP-TN2, sure the CPU may use 9W of power, but what does the rest of the motherboard use? the drives? the 250W power supply and it’s internal fan? The case fan? It all eats power. And the deal breaker, “Up to 8GB of non-ECC RAM”. For what you listed, I’d say a minimum is 16GB RAM.

I think you will be doing “a lot of research” to find components to build a very low power system. 20Wh is not very much power. Maybe a cell phone with a very large internal drive?

As for 4-5TB of storage, two 8TB NVMe drives in a Mirror would be fine, use Gen 3. Gen 4 and 5 use a lot of power and generate a lot of heat.

A few years ago someone posted an actual low power system, I think it was about 20 watts but I do not recall any of the specs, but it was not a fast system. You might do a search for it and you could find some help there.

3 Likes
8

20 W-h isn’t any amount of power at all. It’s a measure of energy, not power. It’s 20 W of power over 1 hour, or 20 J/s * 3600s = 72000J.

This whole thread really doesn’t make any sense because it’s confusing power with energy.

1 Like
9

What is the model of the router? This will help me put perspective on the power available.

While I agree with you on some level, the point hopefully is they can power a 20 Watt item for 1 hour, or in this case they want to use a computer that only uses no more than 20 watts per hour.

Question: Can the router be replaced by the new low power computer? That should be possible, it is only a router. If you then need a switch, find a very low powered switch. Unfortunately the Modem can’t be simulated in the computer. But if you can combine the computer and router, now you have 30 watts of power. I feel that is still way too low, not sure it is really possible. You may need to consider a few more solar panels.

10

What I can’t understand Is how is possible to continusly provide at least those 20w-h of energy, with only solars panel… But probably i’m missing something.

Regarding low power build… You probably will have better choice outside server grade Hw, like with mobile SOC.
I have repurposed an unused XC330 that idle under 10w with 1 SSD (boot), 1 2tb rust disk (backup) and 1 NVME (4-5 apps), plus an Intel dedicated nic. So far so good for a machine that Is up only to received dayli snapshots from my system… But Power need increase consistently when Is not in idle

1 Like
11

Thanks all again. Yes, 20wh is really small, and ram and drives and fans will drag that further down. I have also seen a few threads about people building low wattage servers for minimal tasks, and definitely am considering low power embedded options. I think the key to the Atom is that it is server grade AND has a constant draw, where processors with “turbo” frequencies may idle at 9w, then spike on demand.
More about my setup:
Solar panels = 1.5kwh
Batteries = 11kwh
Refrigerator =1kw/d
Verizon modem (I said router) = 10wh
Pumps, hot water and incidentals = ~1kw/d

In the summertime there’s room to grow. On a day when I get multiple hours of sun, I can “afford” to run something larger. But in the winter, when the panels are covered in snow for two days straight, or the sun doesn’t come out, I need every watt I can spare.
I’m intentionally shooting low, but am trying to avoid investing in a system that will drain my batteries and shut the whole cabin off.
Maybe my numbers are low. Maybe the total math would allow 30 or even 50w. I do know that I’ve already drained the batteries once, this winter, without a server running in the background.
Thanks again for everyone’s thoughts and suggestions.

12

I’m trying to reconcile “off grid” with a modem/router.

Honestly I’d just get a tablet with a large micro SD card and a 5g SIM.

1 Like
13

That must have sucked. Solar during winter does make it tuff.

Wow, the modem takes 10 watts, ouch. But 10 watts is not very much either.

Best of luck to you and I think you will unfortunately have a difficult time getting anything really low.

Links: (Search, you will find a lot more and like I said previously, I really think someone stated they were pulling 24 watts. My NVMe system pulls 42 watts at idle, and it can go way up from there, but I don’t have to use Solar power either, although I would like it.)

2 Likes
14

This thread reminds me of Apollo 13, where the NASA scientists are trying to power up the spacecraft with a blown out power bus. I’ve recently been going down the path of trying to optimize my equipment at home and move to lower power components. A few things I’ve learned:

  1. Forget about hard drives. They consume too much power. Expect a hard drive to consume 6-10watts – idle. Sure, you could script out the ability to spin down and spin up a drive, but if you are writing a steady stream of camera data, you will either need to keep the drive running or find some other, even lower power storage medium to buffer the data.
  2. Even a RJ45 port consumes power. With my low-power switches, connecting a new device to a switch consumes ~0.5-1w of additional power, when idle.
  3. Even if you get either of the CPUs you are suggesting, you may be able to squeeze more power savings by underclocking and undervolting the processors and memory – basically running the machine slower.
  4. You will need a high efficiency power supply, a low power processor, prefer one DIMM of memory if possible. Less chips physically powered, less power drain.
  5. Each of your SSDs will consume idle power, and you can find those measurements by digging into a technical document for the SSD. For example, my 7.68TB U.2 SSD consumes 9.0 watst during heavy reads/11.5W during heavy writes, Idle : 3.6W. You will need to minimize the power consumption of your storage.
  6. You will need to fine tune everything in your computer. You will need to learn how C-states work, because processors will idle at different wattages depending on what C-state the processor can use. In other words, how deep of a sleep can it get to when idle. Different hardware, different drivers, different OS configurations, different power settings will all have a complex involvement in allowing your hardware to reduce it’s energy usage.

Honestly, I like Krill’s advice best. Use a tablet with a very large Micro SD card and a SIM. Find something you can put linux on, so you have strong control over the device. If you need more storage, a LOT more storage, I would look into finding some sort of low-power, flash based external storage. Bonus points if you can automate a workflow that physically powers on the external media (or awakes it from a deep sleep.) Then moves out the security footage to the drive, freeing up space. Once everything’s good, automate turning the device off.

1 Like
15

Thanks for all of your thoughts. I ordered a used 20w SuperMicro A1sdi-2758 from Ebay. Unfortunately, it showed up DOA and I’ve since determined it to be the C2000 bug. Fortunately, SuperMicro is still taking responsibility for the bug, and issued me an RMA. I’ll start with that board, although I read somewhere else that IPMI uses about 6w at idle.
I also thought I’d be smart and buy a UPS for times when the solar batteries run out. Unfortunately, testing that at home reveals that it uses a continuous 10w - probably powering the charge controller. This will continue to evolve.

16

I found this yesterday, it has been around for a year. Low power for sure but not TrueNAS, so you would need to use something else.

You can also search for “ltt nvme nas” and watch the Youtube video he did on it last year. Again, not TrueNAS but still may be exactly what you desire.

2 Likes
17

Something you might look into is I’m sure your solar powered system has some sort of notification when power is low. You can use that to tell the NAS to power down. If your system has the BIOS feature of Power On when Power is restored, then powering back on is easy.

Lets face it, you have a HUGE UPS! Well at least battery power so it should not drop due to unreliable power source. Also, if you used something like a Pico Power Supply, you could run that direct from 12 VDC input power (no converter eating power). Just something to think about.

18

I started to think about the “Mini PC” devices scattered all over the web, but one drawback is that a NAS should definitely have ECC. Someone elsewhere posted a link to this mobile Xeon with ECC, plus room for SATA and M.2 devices. https://www.aliexpress.us/item/3256806183572428.html?spm=a2g0o.order_list.order_list_main.5.3de11802b3gUnu&gatewayAdapt=glo2usa4itemAdapt
This is absolutely do-able. It’s just a question of what features can be eliminated. IPMI probably has to be the first to go.

19

On which latitude your cabin is?
The farther you are from the equator,the bigger the difference is between summer and winter irradiation values.
This means, that in Central Europe for example, you have a 1:6 ratio between winter and summer irradiation.
This means, that your 20Wh in summer goes down to 8Wh.

20

I could go down to about 38W with my Atom based system without any spectacular tweaks.
SO they are low power indeed, btu I would not trust them in a solar only scenario.