chattr - change file attributes on a Linux file system
To add attributes on files and immutable to secure from deletion
create file sample.txt
$ sudo chattr +i sample.txt
To list the file attributes on a Linux second extended file system
$ lsattr sample.txt
----i---------e----- sample.txt
Now change permission , rename , remove force will not be permitted
To unset attribute on Files
$ sudo chattr -i sample.txt
$ lsattr sample.txt
--------------e----- sample.txt
Now its possible to rename , remove , change permissions of the file
sample.txt
To open the file only in append mode and the previous data cannot be
modified
create a text file example.txt
$ sudo chattr +a example.txt
$ lsattr example.txt
-----a--------e----- example.txt
$ echo "this is line two" > example.txt
bash: sample.txt: Operation not permitted
$ echo "this is line two" >> example.txt
$ cat example.txt
this is line one
this is line two
To secure entire directory important_folder and its files
$ sudo chattr -R +i important_folder
To unset it
$ sudo chattr -R -i important_folder
regards,
T.Dhanasekar