Instance type support
Supported instances on the Rackspace cloud for new deployments may change without notice and vary between bring your own license (BYOL) and pay as you go/on-demand (PAYG).
FortiOS supports all Rackspace cloud instance types/flavors with at least 1 GB of RAM.
You can apply a smaller FortiGate-VM license if you are OK with consuming less CPU than is present on your instance. For details, see FortiGate-VM virtual licenses and resources.