Can you put a custom OS on it, wiping their software? I have a network rack in my basement (so, shallow depth, can’t fit a “full” depth server) and I’m looking for a dumb box of hard drives with otherwise simple/supported-by-linux hardware that I can use to build my own NAS. I don’t really want to use unifi’s software for it (plus it’s nice to just run plex/jellyfin/etc directly on the box)

I currently plug a USB3 4-bay disk enclosure into my homelab server for this, but the cabling is messy and it doesn’t support 20TB drives. I could upgrade to a newer enclosure, but I’d rather have a “real” rack mount system with drive bays.

No can’t run custom OS as far as I know; without some seriously hackery. Admittedly UniFi NAS software currently is not nearly as feature rich and enterprise as TrueNAS for example, but it’s all very new. Ubiquiti has had a track record lately of iterating very quickly adding more and more enterprise features into their products. I expect to see more hardware offerings in the UNAS line soon as well. Highly recommend Ubiquiti! I have a complete setup at my house with their switches, routers, APs, and protect cameras. It’s awesome!

I assume the UniFi NAS isn't meant for running Plex, for example. Most people seem to want a general purpose mixed media server, which can handle a bunch of data but where a good chunk of that data is movies/music/books that they want to stream. A good percentage of people probably also want to run docker containers. The $500 for (was it 7?) bays of storage is great, but probably mainly functions as a true NAS, so maybe not what a lot of people want. (I think the term "NAS" is a bit overused and can be deceptive for newer users entering the market)

I fully expect Ubiquiti to add some sort of container / VM support eventually to their UNAS products.

That would be rather delicious.

Their weird status with network speeds quicker than 1gb is irritating, but slowly improving.

Assuming shallow depth is 450mm, you could fit in a Sliger shallow case. My workstation runs in one.

what i did is buy a 19" shelf and put a mini itx board and a few 5.25 cages next to it.

Looks like their $300/4GB/1U/4bay and $500/8GB/2U/7bay half-depth devices with AWS-Annapurna SoC can run either NAS or NVR Linux. Bluetooth in a rackable device is unusual. OS might be replaceable with mainline Debian.

https://github.com/NeccoNeko/UNVR-diy-os/blob/main/IMAGES.md

If it can run Gentoo it might be a big energy savings vs my old off lease machine with ZFS …

There's also a QNAP 1U for $600, which adds M.2 NVME and optional 32GB ECC RAM https://news.ycombinator.com/item?id=40868855

We need more Thunderbolt/USB4-to-JBOD 40Gbps storage enclosure options, for use with Ryzen mini PC or Lenovo Tiny.

At first I was going to balk but then I remembered I paid ~$1.5K for a 12-bay Synology (and again for the 12-bag expansion unit).

This is much larger I think (and it bugs me that it’s not an even number of drives, and the offset of the drives is unpleasant) but it’s rackable so that’s a plus.

The only thing I’d want to know is sound (and I’m sure I can find a YouTube video).

I’ve been looking for an excuse to go all-in on a Ubiquiti setup… Thanks for mention this, I wasn’t aware Ubiquiti had a NAS product.

I believe the UNAS Pro is exceptionally quiet. Agree 7 drive is strange but they wanted their touchscreen so. I expect to see additional hardware units in the UNAS lineup released. Perhaps non-pro and enterprise versions.

Highly recommended Ubiquiti. I have it all throughout my house.

What is the File System? BTRFS or ZFS?

I only wish they do a 2 Bay or 4 Bay version. Or better yet something like Time Capsule. 2 Bay + Ubnt Express.

Mdadm for the raid, btrfs for the filesystem. I expect to see them iterate and add ZFS eventually as well as new hardware units. Perhaps non-pro and enterprise versions.