How to make a Linux File unchangeable ( unalterable ) so that no one can modify it

To make a Linux file unchangeable (unalterable) so that no one can modify it, you can use the chattr utility.

To make a file unchangeable, run the following command:

chattr +i <file>

Replace <file> with the path to the file you want to make unchangeable.

This will set the "immutable" attribute on the file, which prevents it from being modified or deleted by anyone, including the root user.

To remove the "immutable" attribute from a file and allow it to be modified again, run the following command:

chattr -i <file>

Replace <file> with the path to the file you want to modify.

That's it! You now know how to make a Linux file unchangeable so that it cannot be modified.

Note: The "immutable" attribute is a security feature that can be useful in certain situations, but it should be used with caution. If you set the "immutable" attribute on a file that you need to modify later, you may not be able to remove the attribute or modify the file.