Yes I'm aware about ECC support but my budget doesn't allow to invest in a workstation with ECC mobo/CPU at the moment.
Actually that would be a
server motherboard and CPU, not
workstation These do not have to break the bank. Up to 9th generation, Core i3 supported ECC and served as fully qualified low-cost server CPU—but C242/C246 motherboards are getting hard to find.
If I buy another 16GB RAM stick, am I going to be good with 32GB of RAM? It surprises me that 16GB is not enough for just a file server.
It would run with 16 GB, but ZFS is designed to make full use of available resources, and loves RAM.
RAM serves as read cache (ARC) and write cache (up to two "transaction groups"). 2 txg is typically 10 s worth of data: At 10Gb/s, that would be (up to) 100 Gb, or 12 GB. With 16 GB RAM total you'd be either evicting ARC, and hurting read performance, or constraining writes—limiting performance either way.
PSU will handle 5 HDDs and 2x NVMes and a dual 10Gbit network card (Chelsio T520-CR), nothing else and no GPU ofc. What do you suggest for watt power? I have in mind also a Seasonic Gold+ 550w.
PSU guidance from the TrueNAS forum suggests that 450 W is adequate for just that but the 10 drives a Node 804 can accommodate would push this figure to 650 W. It would be a pity not to get it right from the start, and have to replace the PSU to add drives later on.
I liked the Node 804 cause of the dual chamber design which makes easy the access to the disks. What is your suggestion but similar in size? Goal here is to be as small as it can as I don't have so much space in my office.
The 804 is adequate for what it does (up to 10 3.5" in HDD in "consumer style" rather than server-style rack). It is not so "easy" to work with because one has to take a whole 4-drive cage to make any change but that's acceptable for a home NAS.
In (ATX) tower form, I like the Nanoxia Deep Silence 8 Pro ('Pro' variant is important!) because it comes all set up for storage use and has tool-less trays: Much better than converting a FD Define to "storage layout"!
If you're confident you're never going above 6 drives, the Fractal Design Node 304 makes a very nice "shoebox" NAS, but it requires a mini-ITX motherboard which is a rare form factor for socketed servers and bring extra complications because of the limited expansion options (but embedded boards such as the Supermicro X10SDV or A2SDi series are absolutely perfect here).
I found on eBay Chelsio T520-CR (
https://tinyurl.com/5e8y5w2h) for 105€ which is a great price for dual 10Gbit Ethernet card.
A gold, or rather platinum, standard of 10 GbE NIC! Solarflare NICs even go for half that price. Either would be fine in the NAS. (And maybe even in a hackintosh but compatibility with recent versions of macOS is to be checked.)
Add something like a Microtik CRS-305 or 309 switch and you're set.
5 Disks shouldn't be able to provide 900-950mb/s regarding that 4 disks are counted and can provide 220-235mb each one in Raid5?
That seems very, very, optimistic even for a
single and
sequential operation.
Each client will need to access multiple files for editing, possibly seeking into the files (random access!); I'm sure your workload is not purely sequential.