They do make managed switches, but just to be completely clear, my comment was mostly hyperbole. I just found the general combination of security - mindedness and cheap Chinese hardware curious / amusing.

I was wondering… that tp-link probably negates anything remotely resembling security on its own. But yeah, you can update some of these noname boxes easily, others, not so much.

I have dealt with (in a professional capacity) Chinese manufacturers that are under the impression they do not have to provide a working build tree for the kernel, let alone firmware, so its a gamble if you’re not talking to a major Chinese name brand. Mind you, I was ordering hundreds of those boxes, so there was some leverage.

I can second that. We had some really good experiences with ClickHouse and its performance. If it fits the bill, it’s a very nice piece of software.

Hey, great that you chimed in, I agree with the points you’re making. As for my remark regarding amplitude, what I wanted to convey was: in the measurement scenario using the PhyBox smartphone app, OP should see an overall smaller signal envelope if the NAS was properly decoupled, compared to the previous plot.

As for your comment regarding the Nyquist theorem, PhyBox maintains a list of devices and their sensors so it would be possible to lookup the available sampling frequency. There are other factors potentially limiting the sample rate (e. g. switching offl microphone access for the app on Android), but it’s a good starting point.

https://phyphox.org/sensordb/

However, I think we agree this should be solvable without much theoretical effort.

Honestly, I think your approach using the MEMS accelerometer in your smartphone is fine - just make sure to tape the back of your phone firmly to the board to get a rigid connection. This will be of particular importance if you want to do any kind of tuning, as you might measure spurious frequencies if the device is not properly attached.

Smartphone accelerometers are actually used in civil engineering / industrial applications to determine frequencies of e. g. bridges or check for bearing wear. If you are interested, here are some papers:

https://www.spiedigitallibrary.org/conference-proceedings-of-spie/9804/98040C/Identification-of-the-operational-frequencies-of-300-bridges-using-smartphones/10.1117/12.2222097.short#_=_

https://www.scielo.br/j/lajss/a/ZnWZ8T86HHBLFvdksCh7g9s/?lang=en

https://www.mdpi.com/1424-8220/19/14/3143

https://www.mdpi.com/1424-8220/15/2/2980

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9824767/

That being said, the accuracy of the frequency readings is not super important for your application, as what you are after is pretty much only a reduction in amplitude. I would assume spinning hard drives show different responses to different vibrational frequencies, but I did not have the time to research this myself. However, here are two papers that explore what you are trying to do, which I will link since they also mention a few related papers that show the impact of vibrations on hard drives:

https://link.springer.com/article/10.1007/s00542-012-1592-z

https://content.iospress.com/articles/shock-and-vibration/sav00458

This would in theory incentivise to optimize dampening certain frequencies, but I suspect you will quickly get into the realm of overengineering / premature optimization, as the dampening might be good enough to tune out all relevant frequencies without simulations or tuning etc. However, it’s still certainly a worthwhile effort for educational purposes though.

As for a practical approach, I’d probably simply start out with some super cheap foam obtained at the nearest home improvement or crafts store and see how a sandwich using that affects signal amplitude. You could even introduce artifical vibrations using a DC motor with a weight mounted off-center on the shaft, which you can get ready-made for next to nothing on eBay (“vibration motor”, ~ $2).

If you want to get into tuning / experiment / analysis territory, I would like to include additional motivation. Not only might proper decoupling increase the lifetime of your drives, but it could also improve performance. I will include the following video as humorous proof of that:

https://www.youtube.com/watch?v=tDacjrSCeq4

P.S.: I firmly believe that research should be freely accessible, so I feel obligated to mention that all papers linked above are, if not available for free on their respective webpages, obtainable via a certain scientific hub.

I believe it doesn’t really matter much whether you want to protect the environment from vibrations of the machine vs. protecting the machine from vibrations of the environment - in both cases, decoupling the systems is what you want to achieve.

Eventually, you want to build a TMD: https://en.m.wikipedia.org/wiki/Tuned_mass_damper

I personally had to deal with the case of a large format CNC machine transferring stepper motor vibrations into an adjacent office via the wall-mounted brackets it was sitting on. People started to complain shortly after installation since the noise was very audible in the otherwise quiet working environment.

The solution involved placing the machine on a plate mounted via rubber decouplers (see https://www.dayco.com/en/product/decouplers) which in turn was mounted to a shop-built TMD using a rubber core sandwiched between two foam plates. The rubber core works as both mass and absorbs additional vibrations. It was built following a paper, but unfortunately, that was around 7 years ago and I’m not sure I’ll be able to dig the publication out again.

You can in fact simulate the TMD and do the tuning (see for example https://www.mathworks.com/help/simscape/ug/mass-spring-damper-in-simulink-and-simscape.html , though dedicated software packages also exist) but in all honesty, that will probably be overkill for your case.

Having your NAS sit on a 1/2" board of baltic birch plywood resting on a foam sandwich is probably going to do the trick in your case. You can easily create such a sandwich using foam, a rubber mat and some spray glue. Different foam densities will give different results and yield different “tunings” - you may have to play around with this a bit. I could imagine you’ll most likely even be able to skip the second decoupling step (rubber feet/decouplers), in the aforementioned case the second decoupling allowed for another set of frequencies to be dampened (via a different overall rubber hardness) but also brought overall amplitude down.

Don’t use super soft foam, as this will yield a wobbly base, something you probably want to avoid for your NAS. Also, make sure not to attach the base board to anything else apart from the foam, or you’ll transmit vibrations again. If you don’t like the appearance of the foam, you can build a small fence around it that goes up to the top of the base plate.

All that being said, there are also ready-made solutions like speaker dampening feet available: https://www.amazon.com/Tertullus-Speaker-Isolation-Feet-Anti-Vibration/dp/B09QC2L7N3

Most of them are made to decouple subwoofers, so they might fit into the frequency spectrum you specified. Those couls certainly be an affordable and rather quick way to solve the problem.