SELinux in Ubuntu Lab

The following can be completed with Ubuntu 22.x or later.

Installing and Enabling SELinux

The first step is to install SELinux. Start by opening a command line terminal and installing the necessary packages with the apt commands below.

$sudo apt update
$ sudo apt install policycoreutils selinux-utils selinux-basics

Execute the following command with root permissions to enable SELinux on the system.

$ sudo selinux-activate

Set SELinux to enforcing mode:

$ sudo selinux-config-enforcing

Reboot your system. The relabelling will be triggered after you reboot your system. When finished the system will reboot one more time automatically.

$ reboot

Check SELinux status with the following command to ensure that it is in enforcing mode. $ sestatus

To disable SELinux open up the /etc/selinux/config configuration file and change the following line:

FROM:

SELINUX=enforcing

TO:

SELINUX=disabled

Reboot your system for the changes to take effect.

Alternatively you can temporarily put SELinux into permissive mode with the following command.

$ sudo setenforce 0

Note this change will not be persistent (i.e., survive a reboot). It will go back to enforcing later. To enable SELinux again just execute:

$ sudo setenforce 1