I've used rPi 4 as a home server and it croaks under load. Burns through SD cards if you go that route. The USB, while better, similarly does not operate well under load and I've similarly killed USB controllers when I subject them to too many IOPS. This thing is a maintenance nightmare.
If you're just doing a one off server systems you can pick up older HP thin clients with better specs than a pi 4 and real IO for a similar price point.
T630s can be had for around $60 shipped off eBay with 4GB ram and 8-32GB M.2 SATA upgradable to 64GB RAM (spec sheet says 32GB but some have made 64 work) CPU supports ECC but I haven't tried that yet and as much storage as you want to stuff into the SATA slots (1 22x80 and 1 22x47). You're not going to be able to cram as many in a U1. But you will have an actually stable system. I'd put the CPU at the near equivalent of 2 pi 4s - better if you're doing lots of AES.
I've used rPi 4 as a home server and it croaks under load. Burns through SD cards if you go that route. The USB, while better, similarly does not operate well under load and I've similarly killed USB controllers when I subject them to too many IOPS. This thing is a maintenance nightmare.
If you're just doing a one off server systems you can pick up older HP thin clients with better specs than a pi 4 and real IO for a similar price point.
T630s can be had for around $60 shipped off eBay with 4GB ram and 8-32GB M.2 SATA upgradable to 64GB RAM (spec sheet says 32GB but some have made 64 work) CPU supports ECC but I haven't tried that yet and as much storage as you want to stuff into the SATA slots (1 22x80 and 1 22x47). You're not going to be able to cram as many in a U1. But you will have an actually stable system. I'd put the CPU at the near equivalent of 2 pi 4s - better if you're doing lots of AES.