For this deployment example, an ESXi host named esx-svcs01 is installed in Site 1 as shown in SFS with VxRail multisite stretched cluster. It is used as the initial host for a VM running DNS and NTP services. It is also used to host the OMNI VM.
The physical network connections for esx-svcs01 are shown in the Production topology connection details and OOB management connection details sections of the SmartFabric Services with Multisite vSAN Stretched Cluster Deployment Guide. OMNI uses the additional NIC that is connected to the OOB Management to communicate with SFS.
Configuration of esx-svcs01 is shown in the vSAN cluster and services host initial configuration section of the SmartFabric Services with Multisite vSAN Stretched Cluster Deployment Guide. Its IP address and VLAN are configured on the External Management network.
After the configuration steps above are complete, esx-svcs01 is onboarded to the SmartFabric as shown in the ESXi host onboarding section of the SmartFabric Services with Multisite vSAN Stretched Cluster Deployment Guide. It must be on the External Management network to provide DNS and NTP services to the VxRail nodes, and for OMNI to communicate with the vCenter server. Other networks are not required.