VxLAN is becoming de facto standard for the Data Center networking envitoments. In current and future implementations, VxLAN provides an overlay over a Data Center Spine-Leaf networks. It is decoupled from the Underlay which is static and robust.
In the early implementations of Data Center Networks, there was no such a thing that applications are moving around, going from one physical server to another. So the IP information is used for both identity and location of an application.
But in modern data centers, most applications – I believe as of today more than 60% – are installed in virtual machines. And for redundancy reasons or resource management purposes these Virtual Machines are mobile. Ip information of these applications can no longer be used for location. With the early implementations. IP information should be changed according to new location of an application but of course it is not a feasible solution.
The goal with VxLANs and all overlay solutions, separate the identity information from the location information. This is where vxLAN comes in to picture.
Vxlan takes the original message from the application, encapsulates it into a location information, delivers the destination. Once it is arrived to the destination, location information is decapsulated and the message is delivered to the destination application. With VxLAN we are able to create a layer 2 network on top of layer 3 infrastructure.
Key Benefits of VxLan Overlay
- It does not depend on STP to converge the topology. You will not need to worry about or think about STP. Instead Layer 3 routing protocols are used as an underlay.
- No links within the fabric are blocked. All links are active and can carry traffic. In Spanning tree you will not have this option.
- The fabric can load balance traffic across all active links, ensuring no bandwidth is sitting idle.
- In the underlay you will have redundancy, high bandwidth etc. And if anything changes in your underlay, it will not affect your overlay.
