VMware network FLow with two diffrent VMs on different vlan

[RAGGARW]

Hello All

trying to understand the Network Topology .  i have 2 VMs on two different Sub-nets with single vSwitch or with two vSwitch . Can somebody explain me how the traffic will flow to External physical switch  and how they both VM can communicate with each other on different sub nets  ?

[sjason]

Assuming we are talking about VMs that are on VLAN backed networks and the hosts have trunked interfaces carrying all the relevant VLANs. The esxi host knows what mac addresses are local, so if the destination mac isn't local the packet will be forwarded to the physical network via one of the VSS/VDS uplinks. The traffic would be routed by a L3 switch/FW and put on the destination VLAN where it would be received by the ESXi host on its uplink(s).

You can find an overview of vSphere networking here. This document is very old, but the concepts are still the same.

If you are interested in packet walks with NSX and distributed routing, there is an excellent series of blog posts here by John Kozej.