There are three modes of operation for SC Linux.
The first is disabled in this mode.
SC Linux isn't running at all which means the default discretionary access controls are the only mechanism
to secure the operating system.
The next mode is permissive in this mode.
SC Linux is turned on and run in policy but the policy is not being enforced here.
I see Linux simply observes everything that's going on and logs policy violations.
This mode is very useful if you've got the new application that you need to test on your server and
you're not exactly sure how as C Linux will affect said application.
So what do you do in this case you go ahead and install the application and then you can investigate
the log files for policy violations in this mode.
All objects get leave built with a C Linux security contexts just the same.
The final mode is enforcement.
This is the only mode in which I see Linux actually truly protects the operating system.