SELinux is a set of extra security restrictions on top of the normal Linux security tools. It gives the systems administrator a finer grain of control than what the kernel typically provides.

Test if SELinux is running

You can test to see if SELinux is currently enabled with the following command:

selinuxenabled && echo enabled || echo disabled

Turning off SELinux temporarily

Disabling SELinux temporarily is the easiest way to determine if the problem you are experiencing is related to your SELinux settings.

echo 0 > /selinux/enforce

This temporarily turns off SELinux until it is either re-enabled or the system is rebooted. To turn it back on you simply execute this command:

echo 1 > /selinux/enforce

Configuring SELinux to log warnings instead of block

You can also configure SELinux to give you a warning message instead of actually prohibiting the action. On Fedora and RHEL systems that file is located at /etc/selinux/config. You need to change the SELINUX option to permissive like so:

SELINUX=permissive

Note that these changes will not take effect until the system is rebooted, which is why the first section comes in handy on a system you either cannot or do not want to reboot right now.

Completely turning off SELinux

To completely disable SELinux instead of setting the configuration file topermissive mode you set it to disabled like:

SELINUX=disabled

You will need to reboot your system or temporarily set SELinux to non-enforcing mode to create the desired effect like the example above.