June 2003
Beginner to intermediate
944 pages
43h 1m
English
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Name
umount
Synopsis
umount [options] [directory|special-device]System administration command. Unmount a filesystem. umount announces to the system that the removable file structure previously mounted on the specified directory is to be removed. umount also accepts the special-device to indicate the filesystem to be unmounted; however, this usage is obsolete and will fail if the device is mounted on more than one directory. Any pending I/O for the filesystem is completed, and the file structure is flagged as clean. A busy filesystem cannot be unmounted.
Options
- -a
Unmount all filesystems that are listed in /etc/mtab.
- -d
If the unmounted device was a loop device, free the loop device too. See also the losetup command.
- -f
Force the unmount. This option requires kernel 2.1.116 or later.
- -h
Print help message and exit.
- -l
Lazy unmount. Detach the filesystem from the hierarchy immediately, but don’t clean up references until it is no longer busy. Requires kernel 2.4.11 or later.
- -n
Unmount, but do not record changes in /etc/mtab.
- -O options
Unmount only filesystems with the specified options in /etc/fstab. Specify multiple options as a comma-separated list. Add no as a prefix to an option to indicate filesystems that should not be unmounted.
- -r
If unmounting fails, try to remount read-only.
- -t type
Unmount only filesystems of type type. Multiple types can be specified as a comma-separated list, and any type can be prefixed with no to specify that filesystems of that type should not be ...
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