USB Hard Drive Dock with ZFS/TrueNAS (Sabrent DS-UCTB)

[Dopamin3]

I saw Sabrent is selling a 10 bay USB type C docking station (DS-UCTB). It says "NOTE: This multi-bay station does NOT have built in RAID functionality. However, software RAID configurations are possible."

Would this work properly for creating a zpool of drives? From my understanding ZFS needs direct access to the drives (like an HBA flashed in IT mode) and access to the S.M.A.R.T. data. I'm doubting this will happen based on this post on the forums but just wanted to see if there was any newer information.

 

[sretalla]

It's probably using a SATA port multiplier, so this would apply:

Multiply your problems with SATA Port Multipliers and cheap SATA controllers

In the last year or two, we've had a resurgence of users asking about SATA Port Multipliers and cheap SATA controllers. Please, do NOT use port multipliers, and use cheap SATA controllers only after extensive research. SATA controllers and SATA...

www.truenas.com

I doubt that will satisfy anyone, but it's most likely the right answer.

 

[mervincm]

I would guess the USB connection hides any of the SATA peculiarities. That would all be done in the enclosure hardware. I had a 4 bay USB2 era similar device And if I recall, it was seen as a USB hub and usb attached drives to it. That said, other than for testing / curiosity, I wouldn’t be investing in such tech when so many known trusted stable options exist.

 

[sretalla]

I would guess the USB connection hides any of the SATA peculiarities. That would all be done in the enclosure hardware. I had a 4 bay USB2 era similar device And if I recall, it was seen as a USB hub and usb attached drives to it

If that were to be true, there would need to be a full SATA controller chip for each of the 10 disk bays... I don't think so.

As you say, that device shouldn't be connected to ZFS if folks care about the data it would be storing.

EDIT: looking at this: https://sabrent.com/products/DS-UCTB

I see mention of 10 separate ON/OFF power switches, so maybe I'll eat my words and somebody has actually put 10 SATA to USB controllers in that box (maybe why it's $600)... still a terrible Idea for ZFS, maybe more-so with the power buttons as they are.

 

[jgreco]

hides any of the SATA peculiarities.

Huh? What are "SATA peculiarities", aside from, well, y'know, being SATA sucky?

I see mention of 10 separate ON/OFF power switches,

Yes, Sabrent is kind of well known for this sort of thing. I think I have an earlier version of the HB-BU10 on one of the PC's in my office. I like it quite a bit except that I rarely use the switches... great for device charging though.

You can see the power buttons along the lefthand side. This could be because either they failed to pop for the correct SATA drive connectors that allow for hotswap, and/or they expect the hobbyists who are using these to be careless about drive insertions and removals.

so maybe I'll eat my words and somebody has actually put 10 SATA to USB controllers in that box (maybe why it's $600).

There's no particular reason to expect this is true.

I wonder if I could talk them out of one for evaluation purposes. The problem is that every time I do that, I end up with a bit of hardware I'm not too fond of, eating up space on the inventory shelving.

There will always be some evil associated with USB attached HDD's. However, if you really wanted to create a NAS using a small NUC-like device, for tight space deployment, it would be fantastic if these things actually worked correctly, giving the proper serial numbers, not randomly detaching under load.

 

[sretalla]

It's also going to come down to SATA III speeds of 6Gbits (x10) not really going too well together with only 10Gbits of bandwidth via USB-C.

I can only imagine the disaster a SCRUB would cause on a pool of 10 disks attached via that unit.

 

[jgreco]

It's also going to come down to SATA III speeds of 6Gbits (x10) not really going too well together with only 10Gbits of bandwidth via USB-C.

Except that hard drives really don't exceed about 2-3Gbits/sec, and that's only if you get fully sequential runs of blocks. ZFS is a CoW filesystem, so fragmentation tends to prevent the worst case scenarios here. I definitely tackle this argument when people propose to attach disks via iSCSI or FC to their TrueNAS (yes it happens) but 10Gbps for 10 disks is more promising than 1 or 2Gbps for 24 disks.

 

[Etorix]

Even at the "end-of-year" sale price of $500, I struggle to find a valid reason why one would want this USB-C enclosure rather than a SAS expansion chassis.

 

[danb35]

Well, "SAS is scary and USB is familiar" is likely a big part of it...

 

[jgreco]

Well, "SAS is scary and USB is familiar" is likely a big part of it...

Which circles us around to why I wrote the SAS Primer.

 

[danb35]

Indeed.

 

[sretalla]

Or as suggested by @jgreco, if you have a NUC, with no real option to add external SAS connectors, but having Thunderbolt3/USB-C

Not that I'm suggesting a NUC is a good choice for ZFS/TrueNAS, but I've seen many folks who want to do that. (probably many others with "old" laptops which would start to be in the age of having USB-C now too)... likely a source of many lost pool threads in future.

 

[jgreco]

Yeah, okay. It's really the NUC thing that bothers me. I think there's a strong argument for this in certain less-critical situations. Let me see if I can sweet-talk them into sending me a unit for evaluation, and then we can see what happens.

 

[Ericloewe]

So, recent UASP bridges seem to be less sucky than the older non-UASP ones. I can see this sort thing working okayish if the performance is not terrible. 20 Gb/s USB or 40 Gb/s Thunderbolt/USB4 would be a nice improvement, but particularly the Thunderbolt option could get really expensive.

For the crazies among us: Harvesting old Thunderbolt 3 controllers out of HP thin-style Elitebook/Zbook docks and using them to power a chassis like this with a SAS3008 would make a kick-ass setup.

 

[jgreco]

So I just posted the following at their support page.

Good morning!

I am Joe Greco, one of the volunteer community moderators over at the TrueNAS Forums. TrueNAS is a powerful, large scale ZFS based NAS storage system. This morning, we had a discussion on the forum about your DS-UCTB 10-bay USB disk chassis.

USB Hard Drive Dock with ZFS/TrueNAS (Sabrent DS-UCTB)

I saw Sabrent is selling a 10 bay USB type C docking station (DS-UCTB). It says "NOTE: This multi-bay station does NOT have built in RAID functionality. However, software RAID configurations are possible." Would this work properly for creating a zpool of drives? From my understanding ZFS...

www.truenas.com

Due to the way ZFS and TrueNAS identifies disks, we have historically had a really bad experience with users who have tried to attach external arrays via USB. There are questions about whether or not your array might be suitable for certain applications, even if it might not be a preferred solution. In particular, a small footprint pairing with an Intel NUC computer could be very attractive.

I was wondering if a unit could be made available for evaluation. I am not looking to buy a unit, as no one pays me for this "job". I am not offering to "review" a unit or create a YouTube video. I am not even promising a glowing evaluation. I am simply looking to be able to experiment with a unit so that I can clarify some technical questions that we have, especially relating to device identification, serial number handling, SMART reporting, whether or not there's sufficient USB bandwidth during ZFS heavy I/O operations, and other related stuff. You are welcome (and encouraged) to come to the forums to participate and/or answer questions directly if you like.

If there is a way to arrange an evaluation or loaner unit, please reach out to me via the e-mail provided, or come join us on the forums. We love to talk storage.

Guess we'll see. I've purchased a lot of small Sabrent adapters in the past.

 

[Etorix]

Well, "SAS is scary and USB is familiar" is likely a big part of it...

Fair enough, but even before I had read the SAS primer SAS was less scary to me than USB was crappy.

For the crazies among us: Harvesting old Thunderbolt 3 controllers out of HP thin-style Elitebook/Zbook docks and using them to power a chassis like this with a SAS3008 would make a kick-ass setup.

Assuming that the Thunderbolt controller works with TrueNAS.
Assuming that the Thunderbolt enclosure is not a DAS with its own RAID controller.
Then assuming that the enclosure exposes a non-crappy controller : SAS card OK; bunch of cheap SATA controllers, less so… Would manufacturers throw SATA port multipliers in a Thunderbolt enclosure?
And assuming that the economics of it make sense.

 

[Arwen]

Hmm, nobody suggested reading my resource;

Why you should avoid USB attached drives for data pool disks

This subject has been coming up quite often in the last year or 2. Perhaps because of TrueNAS SCALE has brought forth some attention to TrueNAS in general and ZFS in specific. Please note that this is about USB attached storage for ZFS data...

www.truenas.com