Detailed Explanation of Mounting in Linux and the Mount Command Usage

Yesterday, a student asked me to explain the concept of mounting in Linux and its specific usage. So let’s first look at what mounting is.

To access files outside the root directory in Linux, you need to “associate” them with a directory under the root directory. This operation is called “mounting,” and the directory is referred to as the “mount point.” The process of removing this association is called “unmounting.”

The directory for the “mount point” has three requirements: (1) It can be created with the mkdir command (the directory must exist beforehand). (2) The mount point directory cannot be used by other processes. (3) Existing files under the mount point are hidden. Mounting and Unmounting

dir: The mount point is recommended to be an empty directory; devices that are currently in use cannot be unmounted; common command options: -t vsftype: Specify the filesystem type on the device to be mounted; -r: readonly, mount as read-only; -w: read and write, mount as read-write; -n: Do not update /etc/mtab; -a: Automatically mount all devices that support automatic mounting; (defined in the /etc/fstab file, and the mount options include “automatic mount” feature) -L ‘LABEL’: Specify the mount device by label; -U ‘UUID’: Specify the device to be mounted by UUID; -B, –bind: Bind a directory to another directory;Note: To view all currently mounted devices tracked by the kernel: cat /proc/mounts

Note: The above options can be used simultaneously, separated by commas;Unmount command: umountCommand usage format:# umount DEVICE# umount MOUNT_POINTfuser: View processes accessing the specified filesystem:Command usage format:# fuser -v MOUNT_POINTTerminate all processes accessing the specified filesystem: use with caution# fuser -km MOUNT_POINT Command summary: mount, umount, free, df, du, swapon, swapoff, fuserAutomatic Mounting on BootIf you want to achieve automatic mounting of a device at boot, just modify the /etc/fstab file.File mount configuration file: /etc/fstab/etc/fstab and /etc/mtab differences