The following is listed the best practice of FTT (Failures to Tolerate) and FTM (Failure Tolerance Method) on VxRail.
The following is some sample configuration on VxRail.
FTT=0; FTM=Striping (RAID 0)
FTT=1; FTM= RAID 1 (Mirroring)
FTT=2; FTM= RAID 1 (Mirroring)
NOTE: In FTT=3, using mirroring a 3rd witness is created requiring 2 additional hosts. 1 node for the 4th VMDK mirror and one node for the 3rd witness.