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vSphere Distributed Switch Part 2 – Understand How Virtual Machine Traffic Routes

This post helps you to understand  how the virtual machine traffic flows in different scenarios. I hope this post will really helps VMware learners to understand the basics of virtual networking and how the virtual machine communication will happen in different scenarios with other virtual machines.

VM’s connected with Same vSwitch, same port group and VLAN 

VM1 and VM2 are connected to same vSwitch called “vSwitch1″ ,same port group called Production and also same VLAN called VLAN 20 and also both are running in the same ESXi host called ESX1. Network traffic between these VM’s (VM1 & VM2) does not go to physical NICs on the ESXi host and this frames also not forwarded to physical network like physical switch and router because VM’s will communicate within the vSwitch and results in achieving the increased network speed and lesser network latency.

VM’s connected with Same vSwitch, different port group and VLAN 

VM1 and VM2 are connected to same vSwitch called vSwitch1 but VM1 connected to the port group called TestDev and VM2 connected to a port group called Production and also both are running in the same ESXi host called ESX1. Network traffic between VM1 and VM2 goes via a physical NIC attached to vSwitch1 and then to a physical switch and then travels back to a physical NIC on vSwitch1 and then to VM2.








VM’s Running on different ESX host and connected to different vSwicth and  portgroup 

VM1 is running on ESX host called ESX1 and connected to the virtual switch called vSwitch1 and portgroup called Production. VM2 is running on ESX host called ESX2 and connected to a virtual switch called vSwitch1 and port group called TestDev. Network traffic between VM1 and VM2 goes via a physical NIC on vSwitch1 on ESX1 and then to physical switch  and then travel backs to a physical NIC attached on the vSwitch1 on  ESX host and then it will reach VM2.



I hope this is informative for you. Thanks for Reading!!!!!

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