6TB USB drive read only

[NoToy]

Hi folks hopefully someone can help diagnose this problem I have.
I have an externally powered USB drive attached to my 4gb Pi4 but it is only showing up as read only. My other various drives 4tb etc are rw.


I have read the tutorial
https://pimylifeup.com/raspberry-pi-mount-usb-drive/

In the turtorial it showed how to look at mounts and the strange thing when I run cat /proc/mounts I see it seems to be mounted ro - which I assume is read only
/dev/sdb2 /media/pi/My_Bkp01 fuseblk ro,nosuid,nodev,relatime,user_id=0,group_id=0,default_permissions,allow_other,blksize=4096 0 0

I have latest Pi4 update and also installed the latest ntfs by doing
sudo apt install ntfs-3g

sudo blkid shows that its and ntfs partition.
/dev/sdb2: LABEL="My_Bkp01" UUID="4A6A222A6A2212ED" TYPE="ntfs" PARTLABEL="Basic data partition" PARTUUID="2d81d6aa-2ff8-49e1-a709-da4ab467214a"

I would prefer to be able to have the drive auto mount when I plug in the usb cable, but it is looking like I will need to have an fstab entry.
Is there a way to have the drive auto mount, just like other smaller drives?

Regards
Tony

[LTolledo]

mount the drive in fstab using this:

Code: Select all

UUID=4A6A222A6A2212ED   /media/pi/My_Bkp01   ntfs-3g  defaults,noatime,rw,nofail   0  0

[NoToy]

I made that change and unfortunately it hasn't helped.
I restarted the PI and believe the change has taken effect as before the owner was PI but now its root.
I did check by doing a
sudo touch test.txt
but it fails wiith an error that the file system is read only.

This all works perfectly well on 4TB and below drives (in this external case) - could there be a limit of drive size?
Thanks in advace for any help
Tony

[LTolledo]

my NAS is 2 x 8TB formatted as EXT4
no problem with that setup
https://www.raspberrypi.org/forums/view ... S#p1541272

[trejan]

Run "dmesg" and see if there are any errors when you plug in the drive.

[NoToy]

Here is the result of dmesg


[ 1970.963816] usb 2-1: new SuperSpeed Gen 1 USB device number 2 using xhci_hcd
[ 1970.994531] usb 2-1: New USB device found, idVendor=174c, idProduct=55aa, bcdDevice= 1.00
[ 1970.994546] usb 2-1: New USB device strings: Mfr=2, Product=3, SerialNumber=1
[ 1970.994559] usb 2-1: Product: ASMT1153e
[ 1970.994571] usb 2-1: Manufacturer: asmedia
[ 1970.994583] usb 2-1: SerialNumber: 12345678966F
[ 1971.021989] scsi host0: uas
[ 1971.026907] scsi 0:0:0:0: Direct-Access TOSHIBA HDWE160 0 PQ: 0 ANSI: 6
[ 1971.033288] sd 0:0:0:0: [sda] 11721045168 512-byte logical blocks: (6.00 TB/5.46 TiB)
[ 1971.033304] sd 0:0:0:0: [sda] 4096-byte physical blocks
[ 1971.033674] sd 0:0:0:0: [sda] Write Protect is off
[ 1971.033689] sd 0:0:0:0: [sda] Mode Sense: 43 00 00 00
[ 1971.034025] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[ 1971.035380] sd 0:0:0:0: [sda] Optimal transfer size 33553920 bytes not a multiple of physical block size (4096 bytes)
[ 1971.100956] sd 0:0:0:0: Attached scsi generic sg0 type 0
[ 1971.300797] sda: sda1 sda2
[ 1971.306576] sd 0:0:0:0: [sda] Attached SCSI disk
[ 1973.783632] Under-voltage detected! (0x00050005)
[ 1977.943624] Voltage normalised (0x00000000)

[thagrol]

Try the kernel quirk to disable UAS. There's a sticky around somewhere.

[LTolledo]

how are you powering your setup?
am seeing undervoltage alarm in your dmesg

[NoToy]

Im powering my PI with my phone charger USB C Samsung Note.. The external drives have their own power supply, so ONLY the Pie (maybe keyboard and mouse) can use power. The Ethernet cable is even plugged in

[NoToy]

Try the kernel quirk to disable UAS. There's a sticky around somewhere.

I will try this if I get nothing else, but this solution is USB host specific and as this USB device works fine for other drives, then I would prefer not to mess with it.

Regards
Tony

[NoToy]

Hi folks I thought I would reply even if I look stupid.
The problem was the name given to the drive had a strange last character that didn't display properly.
I put the drive in another external enclosure (10 bay) and only then noticed something strange.
I tested it in that drive bay and it worked.
Put it back in the other one, modified the mount command and its working.
Thanks for all your suggestions.

[trejan]

Thanks for posting the solution. Nope. Not stupid at all. That is a really strange issue. Great that you managed to fix it.