What’s in the /etc/sudoers.d/ directory? It’s a group of files with the following format as displayed in the code below. In the example, the file allows a Linux group or an AD group to assume the role of root, via the sudo command. As long as the group uses the correct format, and is located inside the /etc/sudoers.d/ directory, that group will have access to root.
%groupname ALL=(ALL) NOPASSWD: ALL