TrueNAS on NUC with external OWC Mercury Elite Pro Quad RAID Ready (JBOD) 4-Bay Storage Enclosure (or similar)

[nobillgates]

Hi Netizens,

I am planning to move away from Drobo 5N2 (5 bay, populated with 4 x 4TB HDDs of mixed heritage). Notwithstanding the fact it has performed extremely well in the years of service it has provided (contrary to popular experience), the parent companies are struggling so I am looking to go OSS and reuse the 4 HDDs in an external closure (above, or similar) connected to a NUC, such as:

Hardware information​

Processor: Intel(R) Celeron(R) CPU N2930 @ 1.83GHz

RAM module (1 / 1)Transcend 4096 MB TS512MSK64W6H 1333 MT/s

Max RAM: 8GB

Hard drive: 59.63GB

Network card (1 / 2)Intel Corporation 82583V Gigabit Network Connection

Network card (2 / 2)Intel Corporation 82583V Gigabit Network Connection


The above NUC has only USB 2.0 but I do have another that has USB 3.0, that I could repurpose at a pinch, if the differences between 2.0 and 3.0 are significant.

As a Proof Of Concept (POC) I am currently testing in a VM of similar spec (QEMU backend to UTM on MacOS 12.6) to estimate performance and any limitations.

I have seen some (old) posts here and elsewhere decrying the severe idiosyncrasies of USB but was hoping this has changed with more recent incarnations of the technology and TrueNAS support and tolerance of these.

So far, the POC works reasonably well, but may be unrealistic, given most of the [hardware] features are emulated in software.

Any advice gratefully received.

MTIA
;-}

 

[jgreco]

RAM module (1 / 1)Transcend 4096 MB TS512MSK64W6H 1333 MT/s

Max RAM: 8GB

TrueNAS Core has a minimum memory requirement of 16GB. TrueNAS Scale has a recommendation for 16GB RAM, and 8GB is a bit tight for it.

USB connectivity is generally a very bad idea because there are a lot of edge cases which the hardware usually doesn't handle correctly. This includes relatively important stuff like support for disk replacement, which has absolutely been problematic for other people who have tried to use USB.

This feels like a misadventure in the making.

 

[Arwen]

Some USB enclosures don't pass the serial number of the drive to the host server. They make one up. If you use multiple enclosures of the same brand, you might have the same serial number given to the host server, for multiple drives.

Using a multiple disk USB enclosure may return the same serial number for each attached disk.

Some USB multiple disk enclosures are managed by a light weight RAID chip, that you really don't want to use. But now that RAID chip is your funnel into all attached disks to this enclosure.

Further, many USB enclosures don't pass SMART data, so examining disk's internal state, (or running short / long tests), may not be possible.


ZFS generally wants direct access to the disks. USB interferes with that. You may be able to get it to work, but if you have problems, it's possible we would not be able to help, at all. Meaning it may come down to us saying either you are on your own with unusual hardware. Or moving the disks to a "real" setup.



All that said, I have had no problems backing up multiple Linux computers that use ZFS, to an external USB attached drive, which is also ZFS. That seems to work perfectly, (minus the SMART access, which I can get by another method).

But, I would not consider USB a permanent connection for a ZFS drive(s).

 

[nobillgates]

Thanks, all, for prompt responses.

I take your points and after further consideration have decided to continue with Drobo until it fails. Statistically, it could last another 2 years, I estimate.

I have freed up a single 8TB hdd to take local backups of the Drobo device (and will occasionally backup to B2, too) so when the inevitable happens I can test to destruction the enclosure I mentioned. If it works, great. If not, I will simply use it to house JBOD unless and until I find and can afford (perhaps even a proper TrueNAS Mini!) a more permanent solution.

Thanks again.

;-}
P