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

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

Figure 1. Physical Configuration of the Consolidated SDDC


At the physical layer, a pod is a logical grouping of hardware that supports a certain function and is easy to replicate. Pods can have different configurations of server, storage, and network equipment. In large environments, each pod spans one rack, but in smaller environments you can aggregate multiple pods into a single rack.

This VMware Validated Design uses the following types of pods:

Consolidated Pod

The consolidated pod runs the following services:

  • Virtual machines to manage the SDDC such as vCenter Server, NSX Manager, vRealize Automation, vRealize Log Insight, vRealize Operations Manager and vSphere Data Protection.

  • Required NSX services to enable north-south routing between the SDDC and the external network, and east-west routing inside the SDDC.

  • Virtual machines running business applications that support varying Service Level Agreements (SLAs).

Storage Pod

Storage pods provide secondary storage using NFS, iSCSI or Fibre Channel. Different types of storage pods can provide different levels of SLA, ranging from just a bunch of disks (JBODs) with minimal to no redundancy, to fully redundant enterprise-class storage arrays. For bandwidth-intense IP-based storage, the bandwidth of these pods can scale dynamically.


This VMware Validated Design uses a Layer 3 leaf-and-spine network architecture.

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

  • A spine switch is in the spine layer and provides connectivity between racks. Links between spine switches are typically not required. If a link failure between a spine switch and a leaf switch occurs, the routing protocol ensures that no traffic is sent to the spine switch that has lost connectivity.

Regions, Hubs and ROBO Sites


A hub is the centralized provisioning and monitoring components of the SDDC. A hub can be dedicated to ROBO sites (depending on the number of remote office connections required) or a part of the VMware Validated Design for Software-Defined Data Center. In either case, the hub has the capability for fail over between regions in the event of a disaster.


Each region is a separate SDDC instance and can contain one or more availability zones. This VMware Validated Design uses two example regions in the hub: one in San Francisco (SFO) and the other in Los Angeles (LAX).

Table 1. Regions in VMware Validated Design for Remote Office and Branch Office


Disaster Recovery Role

Region-Specific Domain Name

Region A



Region B



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 in each region in the hub.


A ROBO site is a location that you use to support specific services such as manufacturing, hospitals, or call centers. These locations require minimal workload deployment and have hardware located in space constrained rooms.

Table 2. Sites in VMware Validated Design for Remote Office and Branch Office

Site Identifier



New York City, NY, USA based Remote Office and Branch Office


This VMware Validated Design provides guidance about 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 workload backup, archiving log data and application templates.