Oracle Cloud VMware Solution now supports clusters and mixed shapes in SDDCs:

• SDDCs are provisioned with one unified managment cluster that hosts all of the required VMware managment components.
• You can create up to 6 clusters containing up to 64 hosts to manage your workloads.
• Clusters are initially defined with one type of ESXi host, but you can later add hosts of different shapes, as long as all shapes in the cluster have the same processor vendor.
• Each cluster has its own pricing interval.
• Support for selecting ESXi Software version during Add host and Replace host operations.

For more information, see Overview of Oracle Cloud VMware Solution.