Product : VMware, vSAN [SDS]/6.7 U3, ROBO Ent
Feature : Protection Capacity Overhead, Reads/Writes, Data Availability
Content Owner:  Herman Rutten
Summary
Host Pinning (1N): Dependent on # of VMs
Replicas (2N): 100%
Replicas (3N): 200%
Erasure Coding (RAID5): 33%
Erasure Coding (RAID6): 50%
Details
RAID5: The stripe size used by vSAN for RAID5 is 3+1 (33% capacity overhead for data protection) and is independent of the cluster size. The minimum cluster size for RAID5 is 4 nodes.

RAID6: The stripe size used by vSAN for RAID6 is 4+2 (50% capacity overhead for data protection) and is independent of the cluster size. The minimum cluster size for RAID6 is 6 nodes.

RAID5/6 can only be leveraged in vSAN All-flash configurations because of I/O amplification.