Hi all,

I have an issue with my TerraMaster D5-300 (4× 18 TB Toshiba MG09 in Single Disk mode, no RAID) connected via USB to my Unraid server.
This setup has been running for months, but since a recent reboot / USB-stick rebuild the disks no longer show up in Unraid.

System

• Unraid 7.2.2 (paid license, up-to-date, no downgrade option in GUI)

• Mini-PC with Intel platform, Unraid boot from SanDisk USB stick

• External enclosure: TerraMaster D5-300, 4× 18 TB Toshiba MG09ACA18TE, USB connection

• Mode on D5-300: Single Disk (no RAID/JBOD aggregation)

Symptoms under Unraid

• At boot, dmesg shows the TerraMaster and the four disks being detected:

scsi 3:0:0:0: Direct-Access     TerraMas TDAS             0    PQ: 0 ANSI: 6
scsi 3:0:0:1: Direct-Access     TerraMas TDAS             0    PQ: 0 ANSI: 6
scsi 4:0:0:0: Direct-Access     TerraMas TDAS             0    PQ: 0 ANSI: 6
scsi 5:0:0:0: Direct-Access     TerraMas TDAS             0    PQ: 0 ANSI: 6
...
sd 3:0:0:0: [sdb] 35156656128 512-byte logical blocks (18TB)
sd 3:0:0:1: [sdc] 35156656128 512-byte logical blocks (18TB)
sd 4:0:0:0: [sdd] 35156656128 512-byte logical blocks (18TB)
sd 5:0:0:0: [sde] 35156656128 512-byte logical blocks (18TB)

• But once the system is up:

  • lsblk only shows the Unraid boot USB (sda) and the internal SSD (sdf).

  • There is no /dev/sdb–/dev/sde:

ls /dev/sd[b-e]
# -> No such file or directory

• lsusb on Unraid currently shows only:

Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 002 Device 002: ID 0781:5591 SanDisk Corp. Ultra Flair (Unraid boot)
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub

So the disks are briefly detected as SCSI devices, but apparently disappear again and never make it to stable /dev/sdX devices.

UAS quirks already tested

Because this enclosure clearly uses UAS, I tried disabling UAS via boot parameters.

From an Ubuntu Live system on the same mini-PC, lsusb shows:

Bus 004 Device 003: ID 0480:a006 Toshiba America Inc UAS Controller
Bus 004 Device 004: ID 174c:55aa ASMedia Technology Inc. ASM1051E/1053E/1153E SATA bridge
Bus 004 Device 005: ID 174c:55aa ASMedia Technology Inc. ASM1051E/1053E/1153E SATA bridge

Based on that I added the following to Unraid’s syslinux.cfg:

append initrd=/bzroot usb-storage.quirks=0480:a006:u,174c:55aa:u

dmesg confirms the quirks are active:

Command line: BOOT_IMAGE=/bzimage initrd=/bzroot usb-storage.quirks=0480:a006:u,174c:55aa:u
usb 4-1.1: UAS is ignored for this device, using usb-storage instead
usb-storage 4-1.1:1.0: Quirks match for vid 0480 pid a006: 800000
usb 4-1.3: UAS is ignored for this device, using usb-storage instead
usb-storage 4-1.3:1.0: Quirks match for vid 174c pid 55aa: c00000
usb 4-1.4: UAS is ignored for this device, using usb-storage instead
usb-storage 4-1.4:1.0: Quirks match for vid 174c pid 55aa: c00000

Trotzdem: die TERRA-Disks erscheinen nicht dauerhaft als /dev/sdX und fehlen in lsblk.

Cross-checks on other systems

• Windows 11 Live / normal Windows PC:
  TerraMaster wird korrekt erkannt, alle 4× 18 TB Disks erscheinen in der Datenträgerverwaltung.

• Ubuntu Live (auf demselben Mini-PC):
  Alle 4 Platten erscheinen wie erwartet:

lsblk -o NAME,MODEL,SIZE,TYPE
sdb  TOSHIBA MG09ACA18TE  16.4T disk
sdc  TOSHIBA MG09ACA18TE  16.4T disk
sdd  TOSHIBA MG09ACA18TE  16.4T disk
sde  TOSHIBA MG09ACA18TE  16.4T disk

Damit scheint klar:
Hardware (TerraMaster, Platten, Kabel, Mini-PC-USB-Ports) ist OK – das Problem tritt nur unter Unraid 7.2.2 auf.

Frage an die Community / Unraid-Team

• Ist das Verhalten mit 7.2.2 und diesem UAS-Setup (Toshiba 0480:a006 + ASMedia 174c:55aa) bekannt?

• Gibt es weitere Kernel-Parameter / Moduleinstellungen, mit denen ich verhindern kann, dass diese TerraMas TDAS-Devices wieder verschwinden?

• Seht ihr in meinen Diagnostics (angehängt) Hinweise, warum sdb–sde nach dem ersten Scan wieder rausfliegen?

Full diagnostics ZIP from Unraid 7.2.2 is attached.
Jede Idee, wie ich die Platten wieder stabil in Unraid sichtbar bekomme, ist sehr willkommen.

unimatrix-diagnostics-20251125-0736.zip

Edited November 25, 2025Nov 25 by ChrizAlz
Copy paste error

Nov 25 07:22:36 Unimatrix kernel: usb 3-2: USB disconnect, device number 2

Nov 25 07:22:36 Unimatrix kernel: spl: loading out-of-tree module taints kernel.

Nov 25 07:22:36 Unimatrix acpid: input device has been disconnected, fd 5

Nov 25 07:22:36 Unimatrix acpid: input device has been disconnected, fd 6

Nov 25 07:22:36 Unimatrix acpid: input device has been disconnected, fd 7

Nov 25 07:22:36 Unimatrix kernel: usb 3-3: USB disconnect, device number 3

Nov 25 07:22:36 Unimatrix kernel: usb 3-10: USB disconnect, device number 4

Nov 25 07:22:36 Unimatrix kernel: usb 4-1: USB disconnect, device number 2

Nov 25 07:22:36 Unimatrix kernel: usb 4-1.1: USB disconnect, device number 3

Nov 25 07:22:37 Unimatrix kernel: usb 4-1.3: USB disconnect, device number 4

Nov 25 07:22:37 Unimatrix kernel: usb 4-1.4: USB disconnect, device number 5

USB devices are disconnecting; post the output from lsusb -vt to see what remains connected.

root@Unimatrix:~# lsusb -vt

/: Bus 001.Port 001: Dev 001, Class=root_hub, Driver=xhci_hcd/1p, 480M

ID 1d6b:0002 Linux Foundation 2.0 root hub

/: Bus 002.Port 001: Dev 001, Class=root_hub, Driver=xhci_hcd/2p, 20000M/x2

ID 1d6b:0003 Linux Foundation 3.0 root hub

|__ Port 001: Dev 002, If 0, Class=Mass Storage, Driver=usb-storage, 5000M

ID 0781:5591 SanDisk Corp. Ultra Flair

/: Bus 003.Port 001: Dev 001, Class=root_hub, Driver=xhci_hcd/0p, 480M

ID 1d6b:0002 Linux Foundation 2.0 root hub

/: Bus 004.Port 001: Dev 001, Class=root_hub, Driver=xhci_hcd/0p, 10000M

ID 1d6b:0003 Linux Foundation 3.0 root hub

root@Unimatrix:~#

All the devices except for the flash drive are dropping. I would start by booting with a different flash drive, using a stock Unraid install( no key needed, that will confirm if it's a config issue or not.

i solved the issue with:

• usbcore.autosuspend=-1 → USB-Autosuspend komplett AUS

• usbcore.use_both_schemes=y → Nutze alten UND neuen USB-Enumeration-Prozess

• usbcore.initial_descriptor_timeout=10000 → Warte 10 Sekunden (statt 1) auf Antwort

• usb-storage.delay_use=5 → Warte 5 Sekunden nach Device-Erkennung, bevor Storage initialisiert wird
  
  the solution was:
  Kernel-Parameter:

• usbcore.autosuspend=-1

• usbcore.use_both_schemes=y

• usbcore.initial_descriptor_timeout=10000

• usb-storage.delay_use=5

The kernel was simply too impatient and gave up too soon. Now it waits longer and gives TerraMaster time to respond properly.