VMware NSX and vRNI – a customer solution

5 min read
VMware NSX and vRNI – a customer solution

Old World

The landscape of modern IT is constantly evolving and an aggressive shift towards the software defined data centre is arising. Nowadays, virtualisation of storage and networking is becoming as, or even more important than the virtualisation of compute. In this rapidly transforming realm, traditional networking and security can’t keep up with location-agnostic and application-centric workloads and even if they could, there are now simply better ways to solve the problems occurring in traditionally managed data centres. Security, agility, automation and visibility are the key areas where there is a need for new tooling. During a recent customer engagement, we faced all of these issues and to mitigate them, VMware NSX® and VMware vRealize® Network Insight™ (vRNI) were deployed in the environment.


The customer’s main business objective is to provide IT services to a number of hospitals. Security regulations in the health care world (the likes of HIPPA) can be difficult to comply with, especially with traditional security methods such as using perimeter firewalls for east-west traffic control. The customer had an old data centre that contained both virtual and physical workloads, 200+ undocumented applications, Cisco 6500s core switches and Cisco ASA firewalls. As they were facing multiple challenges with this setup, the decision was made to engage Xtravirt to migrate to a new NSX based data centre.


The main challenge the customer had in their previous environment was application traffic visibility, namely the 200+ applications without proper documentation outlining necessary ports to be open in the firewall. The communication between the networking team and application team wasn’t as smooth as one could hope for either which created unnecessary holes in the overall security posture of the company’s IT department. Multiple DMZs from the Cisco ASA firewall did not scale well and the rule sprawl was becoming a problem. The security team was working reactively instead of pro-actively – a known issue with the traditional approach. All of these issues led to the environment becoming unmanageable.

To sum up the challenges:

  • Lack of visibility of the East-West traffic – resulting in poor understanding of the application flows and complicating the security policy, therefore becoming difficult to manage.
  • Communication breakdown between IT teams – back and forth email exchange proves time consuming and slows down the deployments or changes, identifying a need for a tool to provide a “source of truth” of what is actually happening in the environment.
  • Hair-Pinning to the perimeter firewalls and routers – sending traffic for inspection to the physical firewalls and routing to the core switches, even if the workloads reside on the same host. That is a waste of bandwidth. Also, latency sensitive applications might be affected.


The customer decided to build a new data centre with NSX for micro-segmentation and vRNI for visibility and security planning. The next step was to migrate the applications from the old environment to a new one, then monitor traffic flows of the applications to create an adequate security policy.

Goals communicated before the engagement:

  • Use vRNI to monitor applications and services that are running in the current data centre to get a clear picture of the network flows before the migration of the applications to the new data centre.
  • Use vRNI to plan security policies for the environment based on the observed flows as opposed to the (lacking) documentation from the application team.
  • Design a security policy using NSX, based on the vRNI outcome.
  • Monitor the entire network, both virtual and physical workloads to get the full picture of what is happening in the environment. Then design an alert system using vRNI that will help with monitoring and troubleshooting.


After adding Virtual Distributed Switches as Data Sources in the vRNI we watched traffic flows of the applications. With a few clicks, we were able to see all the traffic – ports, protocols, IP addresses – to and from any selected application. To define an application in the vRNI we simply specify the workloads that are relevant. Then the visual graph shows all necessary information as well as recommended firewall rules. We could export interesting data in the CSV file format readable in Excel and use that as a base for Security Rules creation. It is recommended to collect the flows of the application for some time, like a day or two, as not all the ports of the applications are used in the given moment. It could be a good idea to send a request to the DevOps team to sweep through all the functionality of the application, just to make sure all the traffic needed to be allowed in the firewall is actually there in the output graph of vRNI. By default, vRNI collects data every 5 minutes.

Next steps involved creating a Security Policy using a distributed firewall – kernel based East-West firewall used for micro-segmentation. The decision was made to use Security Tags for all of the virtual workloads and IPsets for external ones.

  • The Security Tags allow for dynamic assignment of VMs. For example – you could create a Security Tag called “Web” and configure a Security Policy that will automatically add VMs with the name that contains “Web” to a specific Security Group. This is a useful feature as workloads quite often change IP addresses and location. We are simply shifting from network-based security to an object-based one that allows for agile and location-agnostic applications.
  • IPsets are sets of IP Addresses, subnets or a group of subnets that specify the scope of affected workloads for a given Security Group. In the customer’s environment, the zero-trust model was implemented which means that only necessary traffic is allowed on the Distributed Firewall and everything else is dropped. This type of design ensures maximum security.

Next, the vRNI notification system was used for monitoring the new Data Centre. There are two types of notifications:

  • System notifications, which are pre-defined. The list of notifications contains 100 of the most commonly appearing issues customers face during a deployment. For example, this could be a loss of network connection of the NSX Edge routers.
  • User notifications are defined by user and are very simple to set up. One can simply use a search bar to search for a specific query, for example, Change in the Application “App1” – and create a notification alert with the click of a mouse. Both System and User notifications are customisable. You can specify the severity of the alerts and tags to make searching for the problem easier and quicker, and contact recipients by email to notify a specific person or a team about an issue.


Quite simply, they are spectacular. In my opinion, none of the solutions available on the market could solve the customer challenges like NSX and vRNI. All the goals were met and challenges mitigated. The customer now has a new health care compliant and scalable data centre with full visibility of both physical and virtual traffic. The customer also has a solution that is centrally managed and application-centric with an agile security policy, plus a customised notification system for monitoring and troubleshooting.

One Step Ahead

VMware appears to be reading the future pretty well; by being flexible and adjusting to the market needs, this virtualisation pioneer managed to create a one stop shop for every IT requirement. With the acquisitions of Nicira and Arkin respectively, VMware expanded their catalogue with two extremely powerful and market changing solutions – NSX and vRNI. The first providing micro-segmentation, logical switching/routing and load balancing to name a few, and the second allowing for full visibility of physical/virtual networks and assisting in security planning. The fact that these two work together and give so many unique features is a game changer in the industry. Adding to the mix products like vSAN for storage virtualisation and vRA for automation, makes it even more interesting – all in software, all managed from your browser, location-agnostic and application-centric. This is a software defined revolution and it is happening right now. Join it and stay ahead of the game.

Xtravirt is a leading VMware NSX specialist and has the ultimate combination of deep experience and agility to design and deliver your IT transformation. If software-defined networking is on your roadmap then contact us today.

To find out more visit: https://xtravirt.com/nsx


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