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13

It is sometimes possible to do a power cycle on branch of the USB bus where the device is plugged : # echo suspend > /sys/bus/usb/devices/1-1/power/level # echo auto > /sys/bus/usb/devices/1-1/power/level The 1-1 should be adjusted to your configuration. You can see to which part of the USB tree your device is plugged by running lsusb -t before ...


12

Suppose your usb drive is mounted to /media/usb then it would be sufficient to do sudo umount /media/usb Suppose the your usb is /dev/sdb1 then you could also do sudo umount /dev/sdb1 You may also have a look at the anwers of one of my questions, how to umount all attached usb devices with a single command: Umount all attached usb disks with a single ...


11

Following method works with CentOS 6.2: Requirements: USB flash drive (at least 4 GB, I used a 16 GB one) Download an ISO image from a mirror - I chose the full 1st DVD image to avoid a network install (because it is not clear if the cryptographic package signatures are checked by the installer or not), e.g.: $ wget ...


10

qemu-kvm -hdb <device>, where <device> is the USB stick (e.g. /dev/sdb), should do it (tested with Ubuntu 12.04 on an USB stick and it works). You will need write permission to the device (i.e. be root or change its permissions).


10

Are you using a 64-bit version of Linux with a lot of memory? In that case the problem could be that Linux can locks for minutes on big writes on slow devices like for example SD cards or USB sticks. It's a known bug that should be fixed in newer kernels. See http://lwn.net/Articles/572911/ Workaround: as root issue: echo $((16*1024*1024)) > ...


9

Yes, this can occur if your device is formatted with a filesystem that does not support that kind of permission setting, such as VFAT. In those cases, the umask is made up on the fly from a setting in the fstab (or the hotplugging equivalent). See, most probably, man mount for details. For example, for VFAT, we find: Mount options for fat ...


7

Ok, the summary is that Nautilus uses GVFS and you need to tell udev to use GVFS too when reading the fstab entries, you can do this using: /dev/block-device /mount/point auto x-gvfs-show,ro 0 0 x-gvfs-show will tell udev and anyone interested to use the GVFS helper to mount the filesystem, so gvfs has all the control mounting, umounting, moving mount ...


6

I don't know why exactly, but Renan's answer didn't quite work for me. KVM said to me it couldn't find a bootable drive (despite the usb partition being marked as such). However I've found another solution. Get the USB device VendorID:ProductID with lsusb. Example: $ lsusb ... Bus 002 Device 007: ID 0781:5406 SanDisk Corp. Cruzer Micro U3 Pass that to ...


6

SMART over USB is generally either not possible, or is done with (bridge) vendor-specific commands, so there's no one way to get things done. smartctl knows about a few specific bridge chips. Check the manpage for a list. This is horrible, but the only 100% reliable way to access SMART on a disk is to unplug it from the bridge and stick it on a proper host ...


5

Yes. For example: eject /dev/sda Other answers here that indicate that you require mechanical ejection hardware are incorrect. Unmounting is not the same thing as ejecting. If you unmount a volume, you can immediately mount it back, because the underlying device is still available. In some situations, this could present a security risk. By ejecting ...


5

When you mount a partition, it will show in df -h, and if you umount it, then it will no longer show in df -h fdisk -l uses /proc/partitions and prints out all partitions which are physically connected, but your USB drive is still connected to your PC. When you unplug it, then it will not show in fdisk -l anymore, and you can also check cat ...


5

Have a look under the /sys/ directory. In particular, /sys/block/ contains symlinks to block devices in /sys/devices/. /sys/block/sdX/removable looks like it will read as 1 for a removable device, and 0 otherwise. This gives you a basic check for removability. I'm not sure if there's a better way to check if it's a USB device, but readlink /sys/block/sde ...


4

From my experience in Ubuntu, when you "eject" a USB stick from within Nautilus, the device actually disappears from the system. I'm not sure why this is, but neither Nautilus nor the command line can get it back. I guess the logic is that once you eject a USB stick you don't want it back, but are going to disconnect it. The way I work around this (when ...


4

Well you can connect up to 127 devices (including hubs) to each USB controller so the answer will partly depend on whether those two USB 2.0 ports are on the same controller or on different controllers. Overall the answer is probably several hundred anyway, not that I would recommend that as you'll be sharing the limited amount of I/O that is available ...


4

I would suggest that your drive experienced some kind of hardware failure. The problem isn't the partitions, the problem was encountered when the drive decided to die on you. The original errors you saw during install were probably it failing to write because the disk failed to respond correctly to commands. You can try putting it in a different machine ...


4

Unfortunately it seems that you've just killed your pendrive while trying to install a normal* distro onto it. (See wikipedia on why this is a bad idea.) If there is any chance of bringing your pendrive back to life, it would involve destroying current partitioning. You can try doing that using dd. dd if=/dev/zero of=/dev/sdc bs=4096 count=100 should be ...


4

Reset the device, or the hub it is connected to, and the device should reappear. Here is a small program to do that: http://marc.info/?l=linux-usb-users&m=116827193506484 It works for most USB drives I've tried, but there are exceptions, like my Kingston DT 101 II 4GB, which fails INQUIRY and READ CAPACITY commands after reset, and remains unusable ...


4

It's very doubtful that Ubuntu's beta status has anything to do with your drive issues. Your drive is having difficulties, but there's no way to know for sure if the problems are fatal based on your log output. These are the relevant lines indicating trouble: Mar 31 22:26:06 talk kernel: [13354.939177] end_request: I/O error, dev sdb, sector 488459069 Mar ...


4

Try adding -d sat, -d usbcypress, -d usbjmicron, -d usbsunplus to your smartctl command line, to use a transfer format that can pass through the USB-SATA bridge chip. You can also try connecting it to a USB 2.0 hub / port, which may cause the bridge to behave differently in regards to ATA passthrough. If none of those work, you can always just remove the ...


4

As others have commented I don't believe this is possible in runlevel3. The application in question under GNOME 2.x is called gnome-volume-manager. You can reconfigure it a bit using gnome-volume-properties. screenshot              Given you're in runlevel 3 I don't believe this is an option. You ...


4

If you use the sync mount option on the removable drive, all writes are written to the disk immediately, so you won't lose data from not-yet-written files. It's a bad idea, but it does what you're asking, kind of. Note that sync does not guarantee that you won't lose data. Unmounting a removable drive also ensures that no application has a file open. If you ...


3

USB drives have a chipset that converts USB mass-storage-device commands to IDE or SATA commands, which the drive then receives. Cheap chipsets (which are the majority, I imagine) don't pass on commands correctly to the drive that aren't directly related to reading or writing data from the drive. You are kind of at the mercy of that hardware with USB ...


3

The mount command has two related options: sync All I/O to the filesystem should be done synchronously. dirsync All directory updates within the filesystem should be done synchronously. You can specify them in the mount command's -o option: mount -o sync /mnt/flashdrive Or in your /etc/fstab's fourth column: /dev/sdb1 /mnt/flashdrive ...


3

You seem to forget to unmount the pen drive before unplugging. The data is being written at hte time when you're physically detaching the drive; this results in a corruption. In Nautilus, locate the drive in the left panel, click the eject button near its name. Alternatively, find it on the desktop, right-click, choose 'Eject'. This is the same thing as ...


3

There are several possible causes and things that you might do. The dmesg excerpt suggests a few things: The kernel tries several times to access the device. It seems that each time it does not finish for some reason. There are notices saying not ready after error recovery which indicate that the drive either failed to undergo filesystem checks (although ...


3

I found this answer to work great on my Gentoo system. Please also remember to re-enable your device if it's an important piece of your system (e.g. mouse or keyboard). sudo sh -c 'AUTHFILE="/sys/bus/usb/devices/5-2/authorized" ; echo 0 > "$AUTHFILE" ; sleep 1 ; echo 1 > "$AUTHFILE"' To see what you're disabling/re-enabling: cat ...


3

Ok, so if it satisfies you to have the old pendrive work as the second one, here's how you can do it: Back-up the contents of the old pendrive. Once you have both pendrives attached and your system running, re-partition the old pendrive in similar manner to how the second one is partition - that is to say, make the /boot partition on the old one have the ...


3

Yes, it is possible. It is not very hard but it requires a good comprehension of boot sequence. The "copy" sequence is something like: partition you usb stick and mkfs the partitions. copy the files from source partitions to usb-stick partitions (e.g. using rsync). modify the /etc/fstab to match your new partitions. install a new boot-loader on usb-stick. ...


3

This really helps: http://iso2usb.sourceforge.net/ ISO2USB utility creates bootable USB drive from CentOS/RedHat 5.x/6.x installation disk or corresponding ISO image. Created USB drive may be used to perform installation on machines that lack optical drive. Custom installation disks (with kickstart configuration files) are fully supported. ISO2USB source ...


3

There is also the possibility, that any malware install itself in the MBR/VBR boot sectors of the drive. From there it could be executed automatically if booting from USB storage devices is enabled. As soon as the malware runs, it could install nasty root/bootkits. To clean the MBR of the usb drive from any malware, install a new one. And remove any ...



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