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Linux Security Settings: SELinux and Firewalling
If you're running CentOS or any other Red Hat-derived distribution, we We recommend that you turn off SELinux. Permissive mode was tested and it worked well, just very nagging; the default mode is known to interfere with NMIS. Disabling SELinux is a lot easier than performing the extensive configuration that SELinux needs. To check if SELinux is disabled you can use the command getenforce. If SELinux is enabled in CentOS 6.8, an example of how to disable it is below:
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