Fortigate VM 6.0-Can't access console because it's trying to format the config-drive

Hello Fortifriends!

I'm trying to boot up a FortiGate VM (6.0) on a Xen-based Openstack installation. I'm attempting to configure the FortiGate using cloud-init and the config-drive. Within the Xen environment, the config-drive is implemented as a virtual CD-ROM at device /dev/xvdd .

And that's a big problem, because the FortiGate VM thinks /dev/xvdd is a block device and tries to format it as a log drive. When it fails, it posts a bunch of errors and locks up the console. Does anyone know how to stop the FortiGate from trying to format /dev/xvdd ?