Architecting VMware vSAN 6.2 : vSAN Design Overview : 5.6 vSAN Requirements : 5.6.4 Network Requirements : 5.6.4.7 VLANs
   
5.6.4.7 VLANs
VMware recommends segregating vSAN traffic on its own VLAN. When multiple vSAN clusters are used, each cluster must use a dedicated VLAN or segment for their traffic. This prevents interference between clusters and aid in troubleshooting cluster configuration. VMware strongly recommends that a production design always employ separate VLANs for vSAN traffic.