Mount

Mutable mount points

Oops. A mistake was made. A process or script is filling up /mnt, even though /mnt has nothing mounted upon it.

Immutable mount points

When a mount point is immutable, mistakes cannot fill the underlying file system with junk files. For example, /mnt shouldn't have files in it. It is simply a location to mount devices! The same applies to /media. When a mount point is immutable, devices can still be mounted upon it, but no files can be added to the directory.