VMware Cloud SDDCs are built by default using VMware vSAN, using storage supplied by the cloud provider.
Additional options are available, including the Amazon FSx for NetApp ONTAP storage. When vSAN storage is configured it has vSAN Data-at-Rest Encryption and compression enabled. Key rotation for the vSAN datastore can be done through a VMware Cloud support request. vSAN datastores in VMware Cloud SDDCs offer choices for storage availability, including across multiple hosts, stretched clusters, and the number of hosts. These choices are done at SDDC provisioning.
Inside the cluster, the VM Storage Policies can be customized. VMware vSAN allows customers to choose the affinity and disaster tolerance in stretched clusters, as well as host failures to tolerate (from none to three). This allows an organization to balance capacity, performance, and space efficiency against their tolerance for risk, and their budget.
Elastic DRS (EDRS) is a tool within an SDDC to provision and deprovision SDDC ESXi hosts based on performance and capacity. For clusters with three or more hosts EDRS can be configured flexibly to optimize for best performance, lowest cost, or rapid scale-out. Minimum and maximum cluster sizes can be configured as well.
Ideas to consider:
Changes in vSAN storage policies require a resynchronization process, which is not instantaneous. If your organization customizes storage availability policies to improve capacity will there be a time, perhaps as part of a failover process, where storage availability will need to change? Is that process documented? Is the risk during the resynchronization process acceptable? Are the relevant policies preconfigured to ensure they are correct, saving time and avoiding errors during an already stressful incident?
Elastic DRS has configurations, such as with two-host clusters, where when a particular capacity is reached it will permanently extend the cluster, thereby changing the capacity but also the economics of the deployment. Does your organization monitor and alarm on storage capacity? Will an action by EDRS negatively impact your organization?
