Thanks to the cloud, we have a new wrinkle in our security. We use a cloud-hosting service to host our infrastructure, and this provider also performs management of our hosts (package updates, network configuration, etc). Oracle runs on RHEL6, and our cloud-hosting provider necessarily has root access to the server to perform management of the host. As root they can su to the oracle user and from there get in using "sqlplus / as sysdba". Is there any way to prevent them from gaining access to the database?