3-sites: two active sites + tie-breaker in 3rd site
The use of the Stretched Cluster Witness Appliance automates failover decisions in order to avoid split-brain scenarios like network partitions and remote site failures. The witness is deployed as a VM within a third site.
vSAN 6.7 introduces the option to configure a dedicated VMkernel NIC for witness traffic. This enhances data security because witness traffic is isolated from vSAN data traffic.
VMware, vSAN [SDS]/6.7 U1, Enterprise
SC Configuration, Disaster Recovery, Data Availability