chattr

Change attributes of files or directories. More information: https://manned.org/chattr.

• Make a file or directory immutable to changes and deletion, even by superuser:

chattr +i path/to/file_or_directory

• Make a file or directory mutable:

chattr -i path/to/file_or_directory

• Recursively make an entire directory and contents immutable:

chattr -R +i path/to/directory