Tip: Device is Busy Error

Rai    Linux     cd-rom, device is busy, disc, dvd, Linux, mount, umount, unmount

Unmounting devices in Linux can be a bothersome because of the error “Device is Busy”. This particular error comes up when trying to unmount a drive or device that is being used by the filesystem:


# umount /media/WinXP
umount: /mediaWinXP: device is busy.


One workaround to this is to do a ‘lazy’ unmount:


# umount -l /media/WinXP


The switch -l disconnects the device from the filesystem even if it is being used. This works but quite messy since no further information will be given. If you want a cleaner unmount, fuser commands works well, too:


# fuser -m /dev/sdb1
/dev/sdb1: 1124
# ps axu | grep 1124
rai ... xmms


The ps command showed that xmms is the PID that uses the device /dev/sdb1. Close xmms and the drive can be unmounted safely.