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Red Hat SELinux–How to Enable/Disable

Here is the quick how-to for enabling and disabling SELinux on a Red Hat Enterprise Linux server temporarily and permanently. 

There are 3 modes available with the SELinux-

Enforcing – SELinux policy is enforced and access is denied based on the SELinux policy rules.

Permissive – SELinux policy is not enforced.  Access is is not denied, but what would have been denied if it were enforced will be logged.

Disabled – SELinux is disabled completely.  only DAC rules are used. 

To permanently disable SELinux on the system, update ‘SELINUX=disabled’ in /etc/selinux/config file and reboot the system for the change to take effect

To change between the modes temporarily during run time, use the /usr/sbin/setenforce command with the appropriate mode

/usr/sbin/setenforce 1 will set the mode to Enforced

/usr/sbin/setenforce 0 will set the mode to Permissive

/usr/sbin/getenforce to display the current mode

Refer RHEL 6 SELinux guide for more detailed information

http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/pdf/Security-Enhanced_Linux/Red_Hat_Enterprise_Linux-6-Security-Enhanced_Linux-en-US.pdf

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