UbuntuCommunityAsk!DeveloperDesignDiscourseHardwareInsightsJujuShopMore ›AppsHelpForumLaunchpadMAASCanonical current community chat Ask Ubuntu Ask Ubuntu Meta your communities Sign up or log in to customize your list. The letters (options) added above tell the tool to shut down (-s) with a timeout of zero seconds (-t 00), and to force running applications to close without forewarning the user

First, boot into SAFE MODE and see how it shuts down.