Dear all, I’ve just bought a DAS to have a nice attached storage enclousure for my HDDs. But when I want to create a pool it complains about “duplicate serial numbers”. I’ve read about the problem in different forums, but is there a solution? I wouldn’t like to have an ugly separate disk “power un…

How is the “DAS” unit connected to your TrueNAS? USB is not supported for storage pools and there is no way around that that does not have a very high probability of eventual data loss.

USB 4… DAS also has Raid1 option which should actually mean that the software seeas it as one drive but it doesn’t… It’s a shame… because DAS is a great solution for “home users”… it’s certanly allot nicer than have 2 cheep disk bays connected to the mini pc…

2 cheap disk bays via USB are also not supported at all and will almost certainly lead to data loss. What’s so difficult to understand about this? Do you want to lose precious data? No? Then don’t even consider USB. Get a case with internal disk bays and a main board with four or more SATA ports. D…

Yeah seems to be more of a “I don’t want to use proper hardware” problem… Neither mini PCs nor USB enclosures are recommended for truenas…

[image] mlinko6: USB 4… DAS also has Raid1 option which should actually mean that the software seeas it as one drive but it doesn’t… It’s a shame… because DAS is a great solution for “home users”… it’s certanly allot nicer than have 2 cheep disk bays connected to the mini pc… Understood :-), …

A DAS (consisting of a JBOD, where multiple HDDs are aggregated in RAID1) connected to a (True)NAS via USB. I don’t know if one could build something more unreliable and unpredictable than this… It may sound a bit harsh when one is warned so strongly, but in this forum there seems to be almost eve…

[image] kricka-kracka: I don’t know if one could build something more unreliable and unpredictable than this… I picked up a Supermicro JBOD type expansion chassis for really cheap. There is no motherboard in it but otherwie it is a regular chassis. They have a real Supermicro backplane (eithe…

There are other issues with USB attached disks, than just duplicate serial numbers and reliability: [image] Why you should avoid USB attached drives for data pool disks Resources This subject has been coming up quite often since about 2022. Perhaps because of T…

Direct attached storage Pool Problem - duplicate serial numbers

TrueNAS General

Arwen November 25, 2025, 11:04pm 9

There are other issues with USB attached disks, than just duplicate serial numbers and reliability:

Topic		Replies	Views
USB disks with non-unique serial numbers TrueNAS General Hardware	8	1771	November 29, 2024
Serial # error adding USB drive to new pool (edit) TrueNAS General SCALE , Hardware , TrueNAS_as_VM , USB	6	443	November 11, 2025
Need help creating a pool TrueNAS General	10	84	December 8, 2025
Connecting USB NAS to TrueNAS TrueNAS General	12	1071	March 25, 2025
Multible USB HD's are not show in storrage/drive TrueNAS General CORE , SCALE , Hardware , ZFS	2	124	August 17, 2024

Direct attached storage Pool Problem - duplicate serial numbers

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