The management domain and deployed VI workload domains are logical units that carve up the compute, network, and storage resources of the Cloud Foundation system. The logical units are groups of ESXi hosts managed by vCenter Server instances with specific characteristics for redundancy and VMware SDDC best practices.

The management domain is created by default during bring-up. The Cloud Foundation software stack is deployed on the management domain. Additional infrastructure virtual machines which provide common services, such as backup or security appliances, can be deployed in the management domain as well.

The management domain and workload domains include these VMware capabilities by default:

VMware vSphere ® High Availability (HA)
This feature supports distributed availability services for a group of ESXi hosts to provide rapid recovery from outages and cost-effective high availability for applications running in virtual machines. Out of the box, Cloud Foundation provides a highly available environment for workload domains. There may be additional settings (not set by default) that can increase availability even further. For more information about vSphere HA, see the vSphere Availability documentation at https://docs.vmware.com/en/VMware-vSphere/.
VMware vSphere ® Distributed Resource Scheduler™ (DRS)
This feature dynamically allocates and balances computing capacity across a group of hardware resources aggregated into logical resource pools or clusters. Clusters are the primary unit of operation in Cloud Foundation. DRS continuously monitors use across resource pools and allocates available resources among the virtual machines based on predefined rules that reflect business needs and changing priorities. When a virtual machine experiences an increased load, vSphere DRS automatically allocates additional resources by redistributing virtual machines among the physical servers in the resource pool. For more information about DRS, see the vSphere Resource Management documentation at https://docs.vmware.com/en/VMware-vSphere/.
VMware vSAN ®
This component aggregates local storage disks in a group of ESXi hosts to create a storage pool shared across all hosts in that group. For more information about vSAN, see the VMware vSAN documentation at https://docs.vmware.com/en/VMware-vSAN/.
VMware NSX Manager Automated Backup
It is crucial to take backups of all NSX-T Data Center components to restore the system to its working state in the event of a failure. Until you register an external SFTP server, the NSX-T backups are taken on the SFTP server that is built into SDDC Manager. It is recommended that you register an external SFTP server soon after you upgrade or deploy VMware Cloud Foundation. See Configure an External SFTP Server for File-Based Backups.
You can restore an NSX-T Data Center configuration back to the state that is captured in any of the backups.

Each Cloud Foundation instance is one SSO domain to which all vCenter Servers are joined. See VMware Configuration Maximums for information about the maximum number of supported workload domains.

Note: if you use cross vCenter vMotion between two VI workload domains with dissimilar hardware, you must enable EVC on the corresponding clusters. See Enable EVC on an Existing Cluster in the vSphere product documentation. You can enable EVC on the management domain by selecting the appropriate value in the Deploy Parameters tab of the deployment parameter workbook. For more information, see the VMware Cloud Foundation Deployment Guide.