A physical rack contains two top of rack (ToR) switches. The ToR and inter-rack switches carry all network traffic from the servers including VM network, VM management, vSAN, and vMotion traffic. The ToR switches in the first rack carry all traffic to the enterprise network via two of the uplink ports. The ToR switches provide higher bandwidth as well as redundancy for continued operation in case one of them goes down.
If the installation has inter-rack switches, two uplink ports from each ToR switch on each rack are connected to each inter-rack switch.