我举个例子吧
# ls -al password
-rw-r--r-- 1 root root 6 Oct 16 15:24 password
# chattr +i password
# lsattr password
----i-------- password
# echo "ha" >> password
-bash: password: Permission denied
# chattr -i password
# lsattr password
------------- password
# echo "ha" >> password
# cat password
ha
其实就是给文件加个保护,连root也无法修改了