Disabling uas driver on a USB SSD?

TrueNAS General
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1

I have been experiencing system hangs due to my boot drive / apps drive being on a USB SSD. (Yes - I know this is unsupported.)

USB 3 drives have a greater propensity for disconnects or similar, as do drives that utilise the uas driver.

I am trying to understand whether it is possible to disable the uas driver and get TrueNAS SCALE to load the usb storage driver instead.

Since lsusb utility is not installed with SCALE, here is the relevant part of cat /sys/kernel/debug/usb/devices:

T:  Bus=01 Lev=01 Prnt=01 Port=03 Cnt=02 Dev#=  3 Spd=480  MxCh= 0
D:  Ver= 2.10 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
P:  Vendor=2109 ProdID=0715 Rev= 2.63
S:  Manufacturer=SSK Corporation
S:  Product=SSK USB3.2 SSD Flash Drive
S:  SerialNumber=ABCDEFA75521
C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=500mA
I:  If#= 0 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=uas
E:  Ad=81(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=02(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
I:* If#= 0 Alt= 1 #EPs= 4 Cls=08(stor.) Sub=06 Prot=62 Driver=uas
E:  Ad=04(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=85(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=06(O) Atr=02(Bulk) MxPS= 512 Ivl=0ms
E:  Ad=87(I) Atr=02(Bulk) MxPS= 512 Ivl=0ms
2

Anyone got any ideas?

3

I vaguely recall a file that can be edited to blacklist kernel modules. But, I don’t remember the name. Further, on TrueNAS SCALE it may not survive a reboot, which may be necessary to force un-load the un-wanted module.

A quick search found this;
https://wiki.debian.org/KernelModuleBlacklisting

4

Here is where I am at right now.

I think that what is happening when I get a USB glitch is that it manifests as an I/O error on one of the two pools on the USB SSD, and because the zfs pool property failmode is set to wait, the pool hangs until you issue a clear on it, but you cannot do this because you can’t get access to the UI to do it.

I have now set failmode to continue for both of the pools, which places the pool in read-only status until you can run a clear against it - and I will see if this helps.

sudo zpool set failmode=continue boot-pool

As an aside I also noted that the boot-pool has autotrim=off as standard - and there is no UI available to turn it on.

I have therefore also done sudo zpool set autotrim=on boot-pool because I cannot see how this could hurt, but if anyone thinks otherwise, please let me know.