The physical layer in Standard SDDC contains the compute, storage, and network resources in your data center.

The compute, storage and network resources are organized in workload domains. The physical layer also includes the physical network infrastructure, and storage setup.

Figure 1. Physical Configuration of the SDDC

Workload Domains

At the physical layer, workload domains can include different combinations of servers, and network equipment which can be set up with varying levels of hardware redundancy and varying quality of components. Workload domains are connected to a network core that distributes data between them. The workload domain is not defined by any hard physical properties. It is a standard unit of connected elements within the SDDC.

Workload domain is a logical boundary of functionality, managed by a single vCenter Server. While each workload domain usually spans one rack, it is possible to aggregate multiple workload domains into a single rack in smaller setups. For both small and large setups, homogeneity and easy replication are important.


This VMware Validated Design uses the following types of clusters:

Management Cluster

Resides in the management workload domain and runs the virtual machines of the components that manage the data center, such as vCenter Server, NSX Manager, NSX Controller, vRealize Operations Manager, vRealize Log Insight, vRealize Automation, and other management components.

This VMware Validated Design uses one management clusters that occupies half a rack.

Shared Edge and Compute Cluster

Resides in the first cluster in the virtual infrastructure workload domain and runs the required NSX services to enable North-South routing between the data center and the external network, and East-West routing inside the data center. This shared cluster also hosts the tenant virtual machines (sometimes referred to as workloads or payloads). As the environment grows, additional compute-only clusters can be added to support a mix of different types of workloads for different types of Service Level Agreements (SLAs).

Compute Cluster

Resides in a virtual infrastructure workload domain and runs tenant virtual machines (sometimes referred to as workloads or payloads). You can mix different types of compute clusters and provide separate compute pools for different types of SLAs.


This VMware Validated Design uses a Layer 3 network architecture.

  • A Top of Rack (ToR) switch is typically located inside a rack and provides network access to the servers inside that rack.

  • An inter-rack switch at the aggregation layer provides connectivity between racks. Links between inter-rack switches are typically not required. If a link failure between an inter-rack switch and a ToR switch occurs, the routing protocol ensures that no traffic is sent to the inter-rack switch that has lost connectivity.

Regions and Availability Zones

Availability zone

Represent the fault domain of the SDDC. Multiple availability zones can provide continuous availability of an SDDC. This VMware Validated Design supports one availability zone per region.


Each region is a separate SDDC instance. You use multiple regions for disaster recovery across individual SDDC instances.

In this VMware Validated Design, regions have similar physical and virtual infrastructure design but different naming.

Table 1. Regions in VMware Validated Design


Disaster Recovery Role

Region-Specific Domain Name

Region A



Region B




This VMware Validated Design provides guidance for the storage of the management components. The design uses two storage technologies:

Primary Storage

vSAN storage is the default storage type for the SDDC management components. All design, deployment and operational guidance are performed on vSAN.

The storage devices on vSAN ready servers provide the storage infrastructure. Because this VMware Validated Design uses vSAN in hybrid mode, each rack server must have minimum one SSD and two HDD devices that form a disk group with capacity.

Secondary Storage

NFS storage is the secondary storage for the SDDC management components. It provides space for archiving log data and application templates.