Talk:USB storage devices

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Latest comment: 1 August 2020 by Danuker in topic Device not shutting down

device descriptor read error

Some USB controllers will be loaded with the wrong USB standard applied (e.g. a USB 3.0 controller is initialized with a USB 2.0 kernel module assigned) causing a loss of performance and an error message that looks something like "device descriptor read/64, error -32" at boot time. A supposed fix I found involves issuing the following command as root: "echo -1 >/sys/module/usbcore/parameters/autosuspend". Since I don't have a USB storage device handy it's hard for me to verify that the performance impact was fixed, but I can verify that this at least supressed the error message. This also does not specifically pertain to USB storage devices, but there is not a wiki page specifically for general USB controller usage and I didn't find it in order to create one just to add a single troubleshooting step. Mynis (talk) 21:24, 14 December 2013 (UTC)Reply[reply]

Mount ext4-formatted usb drive so it can be written by the user

Does USB storage devices#As normal user with mount work? When trying to use these option I get errors. I think extra steps, like 'chown'ing the directory, are needed. -- Karol (talk) 02:32, 18 November 2014 (UTC)Reply[reply]

It works fine for me, the ownership of the mountpoint is set according to the gid= argument and its permission according to fmask= and dmask= - exactly the same as for the other files on the mounted drive. I.e., I get the following:
# mount -o gid=lahwaacz,fmask=113,dmask=002 /dev/sdb1 /mnt/
$ ll /mnt/
total 863M
drwxrwxr-x 14 root lahwaacz 8.0K Jan  1  1970 ./
drwxr-xr-x 18 root root     4.0K Nov  7 19:35 ../
drwxrwxr-x  2 root lahwaacz 8.0K Jun 21 12:25 app/
drwxrwxr-x  5 root lahwaacz 8.0K Sep 13 10:03 boot/
...
$ touch foo
$ ll /mnt/
total 863M
drwxrwxr-x 14 root lahwaacz 8.0K Dec  6 23:00 ./
drwxr-xr-x 18 root root     4.0K Nov  7 19:35 ../
drwxrwxr-x  2 root lahwaacz 8.0K Jun 21 12:25 app/
drwxrwxr-x  5 root lahwaacz 8.0K Sep 13 10:03 boot/
-rw-rw-r--  1 root lahwaacz    0 Dec  6 23:00 foo
...
What kind of errors do you get?
Edit: dumb me, I should have read the title first... I have tried it with a NTFS drive, not with ext4. The problem is likely in the gid= mount option, which is not filesystem independent (see mount(8)). In fact, it makes sense only on filesystems not storing Linux file permissions.
-- Lahwaacz (talk) 22:17, 6 December 2014 (UTC)Reply[reply]

devmon

revert edit (since udevil is the only non aur tool for usb mount as user) keeping the new link to the applications list, there is no reason to hide a simple and easily available mount option for users -- Ubone (talk) 05:51, 28 April 2018 (UTC)Reply[reply]

It's not hidden, just described elsewhere. The fact that it is in the official repositories rather than in AUR is not a reason to promote it over the other programs - if people are looking specifically for non-AUR packages, they can easily find it in the list. -- Lahwaacz (talk) 07:52, 28 April 2018 (UTC)Reply[reply]
there really isn't any info on mounting thumb drives besides the udisks page, I don't see why we should waste users time by obfuscating useful information, a minor one liner is hardly a promotion and I probably would have included examples for other tools but I am not familiar with them, I know editors try to keep clean with links to other pages -- Ubone (talk) 08:51, 28 April 2018 (UTC)Reply[reply]

Device not shutting down

I have two comments for Lahwaacz regarding my "Device not shutting down" troubleshooting:

  1. You are correct correct in that udisks is used, and not systemd. I will change that soon.
  2. Do you have any evidence that removing an unmounted-but-still-powered device is safe? I have an USB hard disk that is not solid state, I wouldn't want its heads to crash into the platters or some such. Also, an SSD might be doing things in the background - their algorithms are more complex, and older ones have poor Power Loss Protection

-- Danuker (talk) 10:31, 1 August 2020 (UTC)Reply[reply]

I don't, but I have never heard of a disk which can't park its heads when the power is cut. The think about SSDs is probably more important. You should add references why this is recommended. -- Lahwaacz (talk) 11:29, 1 August 2020 (UTC)Reply[reply]
Thank you for your feedback! But I don't know (yet) what other tools there are and how to use them. -- Danuker (talk) 12:49, 1 August 2020 (UTC)Reply[reply]