please check you configuration and notes regarding this KB: VMware Knowledge Base
I also recommend to read https://storagehub.vmware.com/t/vmware-vsan/vmware-r-vsan-tm-network-design/advanced-nic-teaming/
Please note that vSAN has no load balancing mechanism to differentiate between multiple vmknics. Thus the vSAN IO path chosen is not deterministic across physical NICs.
A simple I/O test performed in our labs:
–70:30 read/write ratio
–64K block size
–four node all flash vSAN cluster
It can be clearly see vSAN makes no attempt to balance the traffic....