Thanks @Bivvo and @deathlessdd !
I agree. It is what I meant in my original post: I want to avoid using SMR disk. I currently use CMR disks.
Good! thanks 
Thanks @deathlessdd
Indeed, I had a Raspberry Pi Storj setup 1 year ago. I made the RPi boot on the storage disk itself (on a dedicated partition). Not the best scenario I suppose but still better than using the SD Card I guess.
Do you recommend one?
I’ve got an RPi3 with three drives attached (2x 2TB, 1x 1TB) configured as one node each using one of these:
I paid a lot less than that when it was on sale but it has worked well for almost a year now. It is generally stated to not buy anything for Storj and use what you’ve got available, but I invested in this dock since I can get use of it if I give up on Storj. The only gotcha I’ve found with it is that if you want to pull or insert one drive it will interrupt connection on the others already docked. So be sure to stop Storj and unmount everything before doing anything in the dock.
Currently im using ORICO 4 Bay USB 3.0 SATA Hard Drive Docking Station/Duplicator for 2.5 inch & 3.5 inch HDD -Black (6648US3-C-V1) - Newegg.ca
But what I would recommend is finding one with a power switch not a button so if the power goes out it will turn back on its own.
perfect
Let me know, if you need help with the monitoring script. 
@deathlessdd, with the 4 bay Orico have you found the same thing that I did, where insert/removal of a disk interrupts communication for any already in the dock?
Not sure what I’m doing different but I’m still on my first MicroSD card I started with in November 2020… haven’t had corruption like you mentioned. I am going to be replacing it with an “endurance” type card though.
I am using this one: SanDisk MAX ENDURANCE microSD card 32GB
Should work a while. Hopefully longer than a state of the art SSD. 
@jeremyfritzen
Yes if you put in a new drive or remove a drive it drops connection…
I had a stack of Sandisk Ultra 32gig maybe they just suck I dont know. I have 3 RPI4 all of them had simlar issues over time, The SDcards get really hot over time. I had to repair the boot a few times… Also these RPI4s werent only for storagenodes though so that could be the issue. All of them were running exporter as well keeping logs and monitoring so that probably added to it.
By the way, of much RAM would you recommend to host 4 nodes (4 HDDs)?
I would think 4gigs is fine but my rpi4 has 8gigs of ram. I also use Ubuntu server for my rpi4s
Thanks.
After checking my RPis, I see that I haven’t a Raspberry Pi 4, Only Raspberry Pi 1, 2 and 3.
Do you think a Raspberry Pi 3 will do the job with good performances?
Yeah for sure, I run on a really weak nas as well, using binary and it runs it fine.
Interesting. Which SDs did you use?
I am using an usb fan and running my node downstairs at 14 degrees - resulting in an operating temperature of max 30 degrees.
Without doing so it was around 50. so absolutely agree on your thoughts. Hope my setup lasts for a long time.
What’s the tool you are using here?
Its just Htop usally already installed.
htop from my RPi3 with three nodes. Not having any issues.
Hmm, the average load on my node is much higher than yours. Could that be due to the disabled swap (to extend SD life)?
I see some say it’ll be fine. I’m not using a RPi3 for Storj, but I thought it wasn’t great especially because it doesn’t have much RAM?
As long as nodes work great and disk can keep up, it’s probably fine, otherwise it may face some memory issue I reckon.
Also less RAM means less cache usable by the OS to optimize process executions, and more swap used which wears off the SD card (unless booted from another drive).
I’m using a RPi4 (4gb RAM, swap disabled) for 6 nodes and it works great and uses only 400-ish MB of RAM when the network is quiet. But it can go up to 800MB when things are more active, or even higher if a disk stalls (but at that point, if the disk doesn’t recover soon enough all the ram could get eaten up until the OOP killer stops the node process - this is not likely to happen with a CMR disk I suppose).
From my experience that’s totally true. On my setup, 2.5" disks have poor performances and take ages to run the filewalker when nodes restart + they regularly cause a lot of io/wait. And for the same capacity, they are more expensive than 3.5" drives.
I have only one 3.5" drive dedicated to Storj, and it works way better. It draws more power and is noisy though. But considering how much more space it can store, it’s quite energy efficient per TB when fully utilized.
Just make sure you choose a case with a power switch that stays mecanically ON so it restarts in case of power outage.
I have this one:
Not sure that’s what you’re expecting but… ^^’ there it is:
here are a couple of suggestions of items that I’ve used in the past:
For an HDD enclosure, I’ve used this before and it works just fine. There’s a little fan in the bottom that can help keep the disk cool(er), and it has a power switch/button that means it will power back on if the power goes out (in alignment with a suggestion someone else had.
I would also agree that moving the root/boot to an SSD is a great idea, one that I have done on all of the rpi nodes that I’ve built. I’ve just used a fairly inexpensive 120GB PNY 2.5" drive. There’s enough space for everything, plus I’ve even gone the path of putting my storj dbs on this too for faster lookups, and increased the swap space on the rpis to try and utilize a bit more of the space on this drive.
to go along with that SSD, I had purchased a “SNANSHI” usb-c enclosure, which was just a clear plastic with little pcb with sata connectors on one side and a usb-c on the other. when I just pulled it up from my purchase history, it appears that they are now selling a different version that is made of aluminum…
in the end I ended up putting all of my rpi’s and ssds into a cluster case, mainly for the organization of them and the cooling is pretty great with those big fans and the previously installed heat sinks.
https://www.amazon.com/gp/product/B08FH3V6GV/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
so to be able to secure the ssd’s to the shelves, I had to strip out the SATA/usb pcb from the ssd enclosre and just connect it bare, directly to the ssd sata connectors. Then I used a really short usb-c to usb-a cable to connect up to the rpi in the shelf above it.
as previously mentioned the only bottle necks I can really think of using a rpi3 (all of mine have been 4s with at least 4GB of RAM) would be the RAM and USB ports being 2.0. The rpi4s have two usb 3.0 ports…
hope this helps.
Why would you do that?
But you said you also have the Microserver that is running anyways. Why would want to waste more electricity?
But your Microserver also accepts 3.5 inch HDDs, so again, why would you want to run an extra device?
I personally would not at all do that.
All of these HDD cases are really inefficient and consume more power than the Pi itself.
