What is the connection between the umount command and the fuser command in Linux?

The “umount” command is used to unmount a mounted file system, while the “fuser” command is used to show which processes are currently using a specified file or file system. When using the “umount” command to unmount a file system, if the file system is still in use by processes, it may result in an unsuccessful unmount. In this case, the “fuser” command can be used to identify the processes using the file system, then terminate those processes before attempting to unmount the file system using the “umount” command. Therefore, the “umount” command and the “fuser” command are often used together when unmounting a file system.