Add a Network Admin link to the Admin Bar

gistfile1.aw

<?php

/**
 * Add a Network Admin link to the Admin Bar.
 */
function network_admin_adminbar() {

	if( is_super_admin() ) {
	
		global $wp_admin_bar;
		
		// Remove the logout link so we can re-add it as the last item
		$wp_admin_bar->remove_menu('logout');
		
		// Add the network admin link
		$wp_admin_bar->add_menu( array(
			'parent' => 'my-account-with-avatar',
			'id' => 'network_admin_adminbar',
			'title' => __( 'Network Admin' ),
			'href' => admin_url( 'network' )
		));
		
		// Finally, add the logout link back
		$wp_admin_bar->add_menu( array(
			'parent' => 'my-account-with-avatar',
			'id' => 'logout',
			'title' => __( 'Logout' ),
			'href' => wp_logout_url()
		));
	}
}
add_action( 'wp_before_admin_bar_render', 'network_admin_adminbar' );

?>