Unresponsive when running `df` or `ls` in a Directory of Mount Points

On my Ubuntu 20.04 machine with multiple external hard drives connected via a 16-port USB 3.0 hub, all these drives are mounted into their own directories in a common parent directory /mnt/data. For example, one of the drives is mounted at /mnt/data/drive001.

Sometimes, the terminal is unresponsive when running the commands df or ls in /mnt/data.

In order to get the command returning some output, one method that worked was to manually run ls /mnt/data/driveXXX until we encounter one that appears to not return any output in seconds, then do a Ctrl+Z, and run sudo umount /mnt/data/driveXXX or sudo umount /mnt/data/driveXXX -f, then continue doing this for all the drives.

Only then does df or ls /mnt/data work. However, running sudo mount -a to remount all the drives back will get frozen. The only way to remount all the drives is to power off and on the USB hub, then run sudo mount -a.

How do we find out the real problem causing this?

These are USB 3.0 drives attached to a USB 3.0 hub connected to a USB 3.0 port on the motherboard

The problem occurs with different drives, not always the same drives.

lsusb:

$ lsusbBus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching HubBus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hubBus 004 Device 055: ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)Bus 004 Device 053: ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)Bus 004 Device 049: ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)Bus 004 Device 044: ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)Bus 004 Device 039: ID 0bda:0411 Realtek Semiconductor Corp. Bus 004 Device 054: ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)Bus 004 Device 050: ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)Bus 004 Device 045: ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)Bus 004 Device 040: ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)Bus 004 Device 036: ID 0bda:0411 Realtek Semiconductor Corp. Bus 004 Device 051: ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)Bus 004 Device 052: ID 0bc2:ab38 Seagate RSS LLC Backup Plus HubBus 004 Device 046: ID 0bc2:ab45 Seagate RSS LLC Bus 004 Device 048: ID 0bc2:ab38 Seagate RSS LLC Backup Plus HubBus 004 Device 041: ID 0bc2:ab45 Seagate RSS LLC USB3.2 HubBus 004 Device 043: ID 0bc2:ab38 Seagate RSS LLC Backup Plus HubBus 004 Device 037: ID 0bc2:ab45 Seagate RSS LLC Bus 004 Device 034: ID 0bda:0411 Realtek Semiconductor Corp. USB3.2 HubBus 004 Device 047: ID 1058:264d Western Digital Technologies, Inc. Bus 004 Device 042: ID 1058:264d Western Digital Technologies, Inc. Bus 004 Device 038: ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)Bus 004 Device 035: ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)Bus 004 Device 033: ID 0bda:0411 Realtek Semiconductor Corp. Bus 004 Device 032: ID 0bda:0411 Realtek Semiconductor Corp. USB3.2 HubBus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hubBus 003 Device 071: ID 0bda:5411 Realtek Semiconductor Corp. Bus 003 Device 069: ID 0bda:5411 Realtek Semiconductor Corp. Bus 003 Device 074: ID 0bc2:ab44 Seagate RSS LLC Bus 003 Device 072: ID 0bc2:ab44 Seagate RSS LLC USB2.1 HubBus 003 Device 070: ID 0bc2:ab44 Seagate RSS LLC Bus 003 Device 068: ID 0bda:5411 Realtek Semiconductor Corp. USB2.1 HubBus 003 Device 067: ID 0bda:5411 Realtek Semiconductor Corp. Bus 003 Device 066: ID 0bda:5411 Realtek Semiconductor Corp. USB2.1 HubBus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hubBus 001 Device 003: ID 1e71:2007 NZXT Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching HubBus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

lsusb -tv:

$ lsusb -tv/:  Bus 04.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 5000M    ID 1d6b:0003 Linux Foundation 3.0 root hub    |__ Port 2: Dev 32, If 0, Class=Hub, Driver=hub/4p, 5000M        ID 0bda:0411 Realtek Semiconductor Corp.         |__ Port 1: Dev 33, If 0, Class=Hub, Driver=hub/4p, 5000M            ID 0bda:0411 Realtek Semiconductor Corp.             |__ Port 4: Dev 47, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:264d Western Digital Technologies, Inc.             |__ Port 2: Dev 38, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)            |__ Port 3: Dev 42, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:264d Western Digital Technologies, Inc.             |__ Port 1: Dev 35, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)        |__ Port 2: Dev 34, If 0, Class=Hub, Driver=hub/4p, 5000M            ID 0bda:0411 Realtek Semiconductor Corp.             |__ Port 3: Dev 46, If 0, Class=Hub, Driver=hub/3p, 5000M                ID 0bc2:ab45 Seagate RSS LLC                 |__ Port 1: Dev 52, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                    ID 0bc2:ab38 Seagate RSS LLC Backup Plus Hub            |__ Port 1: Dev 37, If 0, Class=Hub, Driver=hub/3p, 5000M                ID 0bc2:ab45 Seagate RSS LLC                 |__ Port 1: Dev 43, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                    ID 0bc2:ab38 Seagate RSS LLC Backup Plus Hub            |__ Port 4: Dev 51, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)            |__ Port 2: Dev 41, If 0, Class=Hub, Driver=hub/3p, 5000M                ID 0bc2:ab45 Seagate RSS LLC                 |__ Port 1: Dev 48, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                    ID 0bc2:ab38 Seagate RSS LLC Backup Plus Hub        |__ Port 3: Dev 36, If 0, Class=Hub, Driver=hub/4p, 5000M            ID 0bda:0411 Realtek Semiconductor Corp.             |__ Port 3: Dev 50, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)            |__ Port 1: Dev 40, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)            |__ Port 4: Dev 54, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)            |__ Port 2: Dev 45, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)        |__ Port 4: Dev 39, If 0, Class=Hub, Driver=hub/4p, 5000M            ID 0bda:0411 Realtek Semiconductor Corp.             |__ Port 1: Dev 44, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)            |__ Port 2: Dev 49, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)            |__ Port 3: Dev 53, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)            |__ Port 4: Dev 55, If 0, Class=Mass Storage, Driver=usb-storage, 5000M                ID 1058:25a3 Western Digital Technologies, Inc. Elements Desktop (WDBWLG)/:  Bus 03.Port 1: Dev 1, Class=root_hub, Driver=xhci_hcd/2p, 480M    ID 1d6b:0002 Linux Foundation 2.0 root hub    |__ Port 2: Dev 66, If 0, Class=Hub, Driver=hub/4p, 480M        ID 0bda:5411 Realtek Semiconductor Corp.         |__ Port 1: Dev 67, If 0, Class=Hub, Driver=hub/4p, 480M            ID 0bda:5411 Realtek Semiconductor Corp.         |__ Port 2: Dev 68, If 0, Class=Hub, Driver=hub/4p, 480M            ID 0bda:5411 Realtek Semiconductor Corp.             |__ Port 3: Dev 74, If 0, Class=Hub, Driver=hub/3p, 480M                ID 0bc2:ab44 Seagate RSS LLC             |__ Port 1: Dev 70, If 0, Class=Hub, Driver=hub/3p, 480M                ID 0bc2:ab44 Seagate RSS LLC             |__ Port 2: Dev 72, If 0, Class=Hub, Driver=hub/3p, 480M                ID 0bc2:ab44 Seagate RSS LLC         |__ Port 3: Dev 69, If 0, Class=Hub, Driver=hub/4p, 480M            ID 0bda:5411 Realtek Semiconductor Corp.         |__ Port 4: Dev 71, If 0, Class=Hub, Driver=hub/4p, 480M            ID 0bda:5411 Realtek Semiconductor Corp. /:  Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M    ID 1d6b:0002 Linux Foundation 2.0 root hub    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M        ID 8087:0024 Intel Corp. Integrated Rate Matching Hub/:  Bus 01.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M    ID 1d6b:0002 Linux Foundation 2.0 root hub    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/6p, 480M        ID 8087:0024 Intel Corp. Integrated Rate Matching Hub        |__ Port 2: Dev 3, If 0, Class=Human Interface Device, Driver=usbhid, 12M            ID 1e71:2007 NZXT 

Also noticed in the output of sudo blkiud that 2 drives /dev/sdi and /dev/sde have the same UUID, is this problematic?

Edit: Solved duplicate UUID using sudo ntfslabel --new-half-serial="12345678" /dev/sdi2

/dev/sdi2: LABEL="Seagate Backup Plus Drive" UUID="22E6B3D5E6B3A785" TYPE="ntfs" PTTYPE="atari" PARTLABEL="Basic data partition" PARTUUID="54be5c08-a6d5-4909-85c9-62d6fda3026f"/dev/sde2: LABEL="Seagate Backup Plus Drive" UUID="22E6B3D5E6B3A785" TYPE="ntfs" PTTYPE="atari" PARTLABEL="Basic data partition" PARTUUID="817ab49f-318e-4a0d-9bac-94f8a9cdca7f"/dev/sdf1: LABEL="Elements" UUID="6C4646E14646AC20" TYPE="ntfs" PTTYPE="atari" PARTLABEL="Elements" PARTUUID="20cea80d-7d17-4f56-868d-71ee44300381"/dev/sdj1: LABEL="Elements" UUID="427CE62D7CE61B83" TYPE="ntfs" PTTYPE="atari" PARTLABEL="Elements" PARTUUID="04b6f458-ae99-4c7a-9c00-545e6401212f"/dev/sdp1: LABEL="Elements" UUID="321C481F1C47DC8B" TYPE="ntfs" PTTYPE="atari" PARTLABEL="Elements" PARTUUID="a273a12d-ab32-4170-ab8d-fc7cca5eba21"/dev/sdm1: PARTLABEL="Microsoft reserved partition" PARTUUID="284b5e84-19aa-4568-843c-34a5993109ad"/dev/sdi1: PARTLABEL="Microsoft reserved partition" PARTUUID="7c8f596a-1c06-4e03-9bfb-312f63fbc1b0"/dev/sde1: PARTLABEL="Microsoft reserved partition" PARTUUID="d0eb2a7f-e163-4a31-89b8-b58696ee625a"

/etc/fstab

UUID=d76411a4-2c0d-4b8b-9fb0-e6eb26e525fd /               ext4    errors=remount-ro 0       1# /boot/efi was on /dev/nvme0n1p1 during installationUUID=7CF6-00B7  /boot/efi       vfat    umask=0077      0       1/swapfile                                 none            swap    sw              0       0# External USB drivesUUID=FCB2D174B2D1343C   /mnt/data/drive001     ntfs    defaults,nofail      0       0UUID=6ACE0228CE01ED5F   /mnt/data/drive002     ntfs    defaults,nofail      0       0UUID=16F0FB81F0FB6581   /mnt/data/drive003     ntfs    defaults,nofail      0       0UUID=90AA1250AA123368   /mnt/data/drive004     ntfs    defaults,nofail      0       0UUID=321C481F1C47DC8B   /mnt/data/drive005     ntfs    defaults,nofail      0       0UUID=6CC82B33C82AFB4A   /mnt/data/drive006     ntfs    defaults,nofail      0       0UUID=427CE62D7CE61B83   /mnt/data/drive007     ntfs    defaults,nofail      0       0UUID=6C4646E14646AC20   /mnt/data/drive008     ntfs    defaults,nofail      0       0UUID=1A8A395A8A39341B   /mnt/data/drive009     ntfs    defaults,nofail      0       0UUID=70621B4B621B1586   /mnt/data/drive010     ntfs    defaults,nofail      0       0UUID=C43CED443CED325A   /mnt/data/drive011     ntfs    defaults,nofail      0       0UUID=0C0616040615EF86   /mnt/data/drive012     ntfs    defaults,nofail      0       0UUID=0E1CF8691CF84CE9   /mnt/data/drive013     ntfs    defaults,nofail      0       0UUID=A0C895FBC895D040   /mnt/data/drive014     ntfs    defaults,nofail      0       0UUID=22E6B3D5E6B3A785   /mnt/data/drive015     ntfs    defaults,nofail      0       0UUID=12345678E6B3A785   /mnt/data/drive016     ntfs    defaults,nofail      0       0

grep -i FPDMA /var/log/syslog*

No output.

grep -i /dev/sd /var/log/syslog*

https://paste.ubuntu.com/p/Q8TKZX8TCp/

smartctl -a /dev/sdxx

https://paste.ubuntu.com/p/km2YSPc2Pc/

USB autosuspend is disabled

$ cat /sys/module/usbcore/parameters/autosuspend-1

Ubuntu 20.04 Desktop installation

uname -aLinux x-pc 5.8.0-53-generic #60~20.04.1-Ubuntu SMP Thu May 6 09:52:46 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux