VMware 3V0-23.25 - Advanced VMware Cloud Foundation 9.0 Storage

A vSAN Stretched Cluster requires both compute placement control and storage placement control. To place virtual machines in the appropriate site, the administrator must create VM/Host groups for the two sites. This allows DRS to understand which hosts belong to the preferred site and which hosts belong to the secondary site, and it allows VM-to-host affinity rules to be created for initial and ongoing placement. The administrator must also create a storage policy for each site or site placement requirement. vSAN stretched-cluster storage policies control site disaster tolerance and data locality, including whether objects are mirrored across sites or kept on the preferred or secondary site. VM folders do not control runtime or storage placement. A VM/Host group “across the two sites” is not correct because site separation must be explicitly modeled. Simply placing a VM into a DRS group is not enough unless the site groups and policies already exist. Reference topics: vSAN Stretched Cluster Design Considerations, DRS Host Groups, VM Groups, VM-Host Rules, vSAN Storage Policy Site Locality.

The correct mapping comes from the VCF 9.0 Principal and Supplemental Storage model. vSAN ESA is supported as principal storage for the Management Domain default cluster, Management Domain additional clusters, and VI Workload Domains. A vSAN Storage Cluster is not supported for the Management Domain default cluster because the initial management cluster requires a standard principal storage model, but it is supported as principal storage for Management Domain additional clusters and VI Workload Domains. Fibre Channel is supported as both principal and supplemental storage across all three domain or cluster categories, allowing either initial cluster creation or later datastore expansion. NFS v4.1 is supplemental-only across these categories. NFS can be principal only when using NFS v3; NFS v4.1 is used as supplemental storage after the domain or cluster exists. These statuses align with VCF’s distinction between principal storage, which is used during workload domain or cluster creation, and supplemental storage, which is added after creation for workloads or data-at-rest use cases. Reference topics: Storage Models, Principal Storage, Supplemental Storage, vSAN ESA, Storage Cluster, Fibre Channel, NFS.