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**Amun-Ra** · Sep 26, 2006, 12:33 AM

Re: unable to write to usb mp3 player - how to change permissions for a device

Allright,

you have the same Problem, I guess, that most users have. Only Root is allowed to mount a Device. So If your System mounts a pluged in Device automaticaly (you didn't mount it yourself), you'll always have the right to read but not to write. Same thing, if you mount manualy.

Here is a solution, but this has two considerable disadvantages. Thats why these came first:
1. You'll always have remember the Device Name. If you plug in another USB Device, like an external HDD, You'll get the same result, Read and Write.
2. Every User has these rights, not only you. Is just your System. OK. If not theres a possibility to increase Security a little.

But now, the solution:

1. Create a Directory, either in the "/"-Directory or in another one called something like "/usbstick". But / is the best way to avoid further complications.
2. In wich fs is your mp3-player formatted? You don't know? Plug it in, mount it, type "fdisk -l | grep sda" (if that doesn't work, try without "| grep sda", and search the output. You mounted it, so you know the Devicename). Remember the Device-name too. You'll need it later.

For now, I asume it's FAT32/VFat

3. Edit your fstab-file(/etc/fstab). Just add the following lines:

# allows user to mount <---- This is a Comment
/dev/sda1 /usbstick vfat user,umask=0,noauto 0 0 <---- External Drives are usually
mounted as SCSI. sda1 must
be replaced by the right
Device name. /usbstick is the
path to your created Dir in /.

From now on you'll have to remember, whenever using an USB-Device, that it might be recognized as sda1. So watch out. Make sure, when you proceed like this, that you'll mount no other external device. And when you want to wright files to your RIO CALI, make sure there is no other Device mounted as sda1 (or whatever Device-Name it has).

I hope these steps are comprehensible. If not, just post a reply.

Amun-Ra

**aussiedude** · Nov 19, 2006, 07:48 PM

Re: unable to write to usb mp3 player - how to change permissions for a device

Originally posted by Amun-Ra

From now on you'll have to remember, whenever using an USB-Device, that it might be recognized as sda1. So watch out. Make sure, when you proceed like this, that you'll mount no other external device. And when you want to wright files to your RIO CALI, make sure there is no other Device mounted as sda1 (or whatever Device-Name it has).

One way to overcome this problem (unless you have 2 identical thumb-drives for example) is to mount the device "by-id".
Before attaching your USB device do this:
ls /dev/disk/by-id
You should see something like this:
ata-WDC_WD400BB-00DEA0_WD-WMAD12381334 ata-WDC_WD400BB-00DEA0_WD-WMAD12381334-part6
ata-WDC_WD400BB-00DEA0_WD-WMAD12381334-part1
ata-WDC_WD400BB-00DEA0_WD-WMAD12381334-part2
ata-WDC_WD400BB-00DEA0_WD-WMAD12381334-part5
Make note of the disks already seen by your system. In the example above there is one HD (with 4 partitions).
Then attach your USB device run:
ls /dev/disk/by-id
You'll get something like this:
ata-WDC_WD400BB-00DEA0_WD-WMAD12381334 ata-WDC_WD400BB-00DEA0_WD-WMAD12381334-part6
ata-WDC_WD400BB-00DEA0_WD-WMAD12381334-part1 usb-Myson_Century,_Inc._USB_Mass_Storage_Device_100
ata-WDC_WD400BB-00DEA0_WD-WMAD12381334-part2 usb-Myson_Century,_Inc._USB_Mass_Storage_Device_100-part1
ata-WDC_WD400BB-00DEA0_WD-WMAD12381334-part5
In the example there is a USB mass storage device with 1 partition.

Now you know the "id" of the device you can edit fstab substituting /dev/sda1 with /dev/disk/by-id/usb-Myson_Century,_Inc._USB_Mass_Storage_Device_100-part1 in Amun-Ra's example, so it should look like this:
/dev/disk/by-id/usb-Myson_Century,_Inc._USB_Mass_Storage_Device_100-part1 /usbstick vfat user,umask=0,noauto 0 0
Using this method you should not have a problem with the device being seen as sda1 or sda2 etc.

**KDE Dragon** · Nov 30, 2006, 02:50 AM

Re: unable to write to usb mp3 player - how to change permissions for a device

I hope you don't mind if I jump in on this thread. I have a Rio Forge and I can't even get Kubuntu to "see" it when I connect via usb. The OS "sees" my external usb HD and mounts it by default. It also "sees" my Flash memory stick and flash memory card reader as soon as I connect the drive or stick a card into the reader, but it will not "see" my Rio Forge for some reason.

I read the reply about how to update /etc/fstab and I've done so many times in FreeBSD, but I would like to be able to mount my Rio manually before I change my fstab file. So far, this is what I've done after reading the thread and the advice therein:

# dir /dev/disk/by-id

ata-_I_E_O___T_-_6_0_B_________________________________________
ata-Maxtor_32049H2_B_L243NJTC
ata-Maxtor_32049H2_B_L243NJTC-part1
ata-Maxtor_32049H2_B_L243NJTC-part2
ata-Maxtor_32049H2_B_L243NJTC-part5
usb-Rio_Forge_0002F5A7C1A5CA1F
usb-USB2.0_CardReader_CF_RW_730415536500
usb-USB2.0_CardReader_Combo_730415536500
usb-WDC_WD80_0BB-55HEA0_10000001045E
usb-WDC_WD80_0BB-55HEA0_10000001045E-part1

Okay, something is able to "see" the usb-Rio_Forge... but fdisk does not:

# fdisk -l

Disk /dev/hda: 20.4 GB, 20491075584 bytes
255 heads, 63 sectors/track, 2491 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/hda1 * 1 2385 19157481 83 Linux
/dev/hda2 2386 2491 851445 5 Extended
/dev/hda5 2386 2491 851413+ 82 Linux swap / Solaris

Disk /dev/sda: 80.0 GB, 80026362368 bytes
255 heads, 63 sectors/track, 9729 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

Device Boot Start End Blocks Id System
/dev/sda1 1 9728 78140128+ 7 HPFS/NTFS

So, assuming a vfat file system, I created a mount point (as root) named /mnt/ipod since that's what Amarok requires for a compatible mp3 player and then I tried to mount it:

# mount -t vfat /dev/disk/by-id/usb-Rio_Forge_0002F5A7C1A5CA1F /mnt/ipod
mount: No medium found

At this point, I'm very open to suggestions.

KDE Dragon

**penguin.ch** · Nov 30, 2006, 05:41 AM

Re: unable to write to usb mp3 player - how to change permissions for a device

KDE Dragon,

have you ever tried to (re-) format this "Rio" disk? For what you post here, makes me think that there is no valid file system table on this disk - otherwise you would get something along the lines of "-part1", "-part2" etc. pp.

I this were my disk, I would launch GParted to have a closer look at it ;-)

HTH
Birdy

**KDE Dragon** · Dec 02, 2006, 02:24 AM

Re: unable to write to usb mp3 player - how to change permissions for a device

I this were my disk, I would launch GParted to have a closer look at it ;-)

HTH
Birdy

Thanks for the Reply Birdy. I did as you suggested by downloading and running GParted, but no joy! Kubuntu just does not "see" my Rio Forge and I don't know why. GParted only identified my boot drive and my (USB) external data drive. Any other ideas?

KDE Dragon

**askrieger** · Dec 10, 2006, 08:36 PM

Re: unable to write to usb mp3 player - how to change permissions for a device

If Kubuntu (actually the udev system, which is part of Linux) is, in fact SEEING the device in /dev/disk/by-id/, but is not seeing any partitions, I would draw the conclusion that the RIO Forge is not using a standard file system like vfat.

Does this device work under either Mac OS-X or FreeBSD, (or even, windoze)? If so, you should be able to see the partition table in that operating system (maybe not in windoze). There is a standard list of partition type IDs, that you can look up. I remember seeing it on a Red Hat site several years ago, but you can certainly Google it. If you can identify the file system, we can probably work with it.

Yet another possibility, is to see what you can find out from RIO tech support.