I have a Netgear ReadyNAS Ultra 4. It works fine, but it’s 11 years old and I expect it will fail soon.
I’d like to replace it before it dies, but a new Synology or QNAP unit will inevitably go EOL and put me in the same situation. Any suggestions for a compact TrueNAS build? I would like SSD caching and the ability to upgrade to 10GB networking in the future.
You can make a pretty nice mini-NAS out of a Fractal Design Node 304, or a Silverstone CS381B. The Node 304 is mini-ITX, so only one slot for expansion. Mini-ITX with 10G onboard is a rare combination, and pretty much doesn’t exist outside of specialty boards from Supermicro or Asrock. The CS381B is mATX, which is also kind of a rare thing these days, but nice if you want to add more storage, or maybe a decent GPU down the road.
Fractal 804, because it takes a uATX board that’s expandable so you can attach 40G qsfp+ or even fancier stuff, and holds 8x3.5" if you need it.
Populate 6/8 drives in a single raidz2 leave 2 slots for spares.
Alternatively. Node 304, ASRock rack x570d4i-2t and btrfs instead of zfs, so that you can start with 10Gbps and expand drive capacity gradually. Start with a pair of 12T or 18T drives in a mirror, then add a third/fourth drive, then upgrade smallest and so on. You can expand/upgrade btrfs over time more easily than you can a zfs vdev - this is more financially efficient.