A problem with small form factor NAS boxes is that, you have to use SSDs or 2.5” HDDs that have limited storage capacity (~ 2 TB). The SSDs limit bulk storage and increase the price.
From pricing perspective, a two bay synology NAS is $300. You can add a lot of good cheap NAS storage.
Exactly. I searched a lot for a small form factor ZFS backup server. The vast majority of mini PCs don’t expose a PCIe or eSATA expansion slot. You can connect HDDs with USB, but USB connection is not preferred with ZFS.
The mini PCs can contain dual SSD, but, as noted, the storage is limited and the price is high.
The closest options I found are: RockPro64, Odroid HC4, AsRock Deskmini X300, ZimaBoard, RPI CM4, each having own problems. One may build one from an mITX motherboard, but frankly that may also cost about a TrueNAS mini (which is quite large). Synology boxes are nice, but I want ZFS!
If someone knows a small low power system for a ZFS backup server (like a passively cooled SBC or PC with sata port that can be used to connect HDDs placed outside box due to size limitation, or at least something that is portable), including a DIY build, I would love to take a look.
What I've found as a good compromise is "small-form-factor" pcs, like the HP *desk SFF.
They usually come with mostly full-size components, so they're quiet, take regular DIMMs, etc.
I have an EliteDesk 800 g2 SFF which can take, OOB, three 3.5" drives and one 2.5". If you chuck the optical drive, there's space for a second 2.5".
If you're not afraid to take a dremel to it, the original 2.5" can be modified to house a 3.5" and you could probably stack one or two more 3.5" under one of the existing cages.
You'll also probably want to stick some fans in there somehow with all the drives, but there's space enough. It doesn't have enough SATA ports, but you can find half-height PCIe controllers.
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If you don't want to hack on a case, the most compelling I've found is using one of those MBs with integrated intel CPU. Some of them should be powerful enough for ZFS and can take PCIe cards. You can put all this inside a Fractal Design Node or something similar.
For $455, you can buy an i3 CPU, motherboard with a 2.5G NIC, 16GB RAM, case and power supply to handle 4 spinning disks and an NVMe M.2. Is it tiny? No. It is, however, good enough to be your primary server for anything not ridiculously compute-intensive, 5-10x faster than the Pi, with 2-4x the RAM and much better bandwidth.
You trade off physical size and electrical power -- but if you want 4 spinning disks, that's going to be the same across builds. In return, you get repairability, upgradability, and probably better cooling.
Unfortunately, the Ryzen 3 1200 -- as with most Ryzen chips -- doesn't have an integrated GPU. You would need to find some sort of video card and occupy your single PCIe slot.
A properly designed server motherboard would have a basic VGA port and an IPMI port, but buying those retail bumps up the price ridiculously. The NUC-style machines always have integrated video, sometimes really good (non-gaming) video, but offer only a single SATA port and a single M.2 slot.
It's just something I've found in a quick search. Current availability differs from the place to place but it's not a big broblem to find a CPU with G suffix.
My point - you can find a slightly older solution for less than $200, if you are okay to take some time to find it.
'Server' requirements are moot when we are talking about an extremly budget solution.
And honestly, as a person who extremely benefited from the existence of BMC/iLO/iDRAC - it is not that required for some cheap ass storage solution at home.
Like okay, you did wired another ether link for a BMC, installed OS aaaand... if something wrong with the box it is almost always requires to be near it to resolve the issue.
Edit: personally I have some low power GPUs laying around what can be used for the initial setup.
It was easier when you could fit some S3 Trio card on any machine, but still..
From pricing perspective, a two bay synology NAS is $300. You can add a lot of good cheap NAS storage.