Data Center

Network Virtualization in Data Centers: When the rubber meets the road!

by Sandeep.Singh.Kohli on ‎08-26-2013 01:01 AM - last edited on ‎10-28-2013 01:26 PM by bcm1 (4,867 Views)

As customers start deploying network virtualization solutions using Overlay technology in production environments, it becomes apparent that they need a gateway solution to connect their virtual workloads to the physical infrastructure in their data centers. Brocade worked in collaboration with VMware to develop the Brocade VCS gateway for NSX to help our customers do just that.  Based on what we announced about the gateway, I want to achieve two things in this write-up - plain and simple. 1> Help articulate how VCS Gateway for NSX helps you seamlessly transition to a virtualized infrastructure while continuing to leverage your physical IT resources and 2> more broadly touch upon why a highly resilient, automated and efficient “underlay” networking infrastructure is needed to improve the predictability of your Overlay network solution and reduce complexity. 


Let’s tackle the first point. A typical data-center has several hardware resources running physical workloads. This could include bare metal servers running non-virtualized or mission-critical applications and databases, physical storage devices and specialized hardware running network services. In fact, although it sounds counter-intuitive, most host servers run physical workloads even though there are more virtualized workloads but this point is perhaps a topic for another blog.  So, getting back to our topic, how do we connect the new virtualized infrastructure you are building with your physical resources? We need something that terminates the VXLAN tunnels and sends that traffic to the physical resources, since the physical devices are not VXLAN aware. This is where the Brocade VCS gateway comes in. The gateway translates your virtual VXLAN tunnels connections to VLAN towards Physical destination points.




So that’s the fundamental function of a gateway in the simplest terms. The VCS Gateway, powered by VCS fabric technology, offers enhanced functionality with features like Logical Chassis, allowing multiple Brocade VDX switches within a fabric to be connected as one logical switch. The single logical interface into the fabric delivers operational simplicity because the NSX controller sees multiple gateways as one logical chassis. Furthermore, because the gateway is built on VCS fabric technology with load-balanced multipathing at Layer 1 and 2, the gateway is highly resilient to support mission-critical deployments. These resiliency and simplicity benefits are standout differentiators for the VCS gateway in addition to the scale and performance benefits that hardware gateways provide.


Moving on to the second point on why in general you need a resilient networking infrastructure as an underlay for your overlay. One important point that comes up while talking to customers about Overlay technology is the uncertainty regarding the predictability of the solution (performance and availability). One way to look at the predictability of an overlay solution is to look at the risk of the solution;

Total risk =

Risk due to the predictability of the overlay software +

Risk due to the predictability of the hardware network underlay +

Risk due to the predictability of the interdependence between underlay hardware and overlay software.

You need to ensure that the risk for each of the three parts is as low as possible. Therefore, to increase the predictability and reduce the risk of an overlay solution, you need a robust underlay such as the one delivered through highly resilient fabric of switches based on VCS fabric technology that deliver industry’s best performance and availability. This also reduces the risk due to the predictability of interdependence between the underlay and overlay. In addition, if the physical network is complex to deploy and maintain, it creates a significant operational burden and expense which should be minimized. VCS fabric technology provides the automation and efficiency that minimizes the complexity and is a critical foundation for your infrastructure.


Lastly, won’t it be just incredible when your underlay VCS network also acts as a gateway? Since the gateway functionality is built on the VCS Fabric technology, if you have the VCS fabric as your underlay network, you won’t need a separate, dedicated gateway to do your VXLAN to VLAN conversion when the gateway functionality is enabled across the fabric. This leads to maximum utilization of your networking resources and lowers your total cost.




In general, there is lot of excitement about the choice Brocade provides to customers which includes this support of Overlay based NV solutions.  And with the gateway solution, Brocade is enabling its customers to seamlessly transition to cloud architectures while leveraging and maximizing the investment of their physical resources. This is a disruptive time we live in, but Brocade is laser focused on helping customers along a smooth, non-disruptive journey to the cloud.


To learn more, please visit the VMworld Brocade booth (#1513) at the Moscone Convention Center for demos on Brocade VCS Gateway for VMware NSX with an EMC storage VNX series. In addition, technical experts will discuss the gateway at a session titled “Advanced Network Designs for Data Center Transformation” today at 5:00 pm in Moscone West Room 2014.


More information on the VCS gateway with VMware:


Good introduction to the gateway technology: