Category: VCDX Process

What does it take to achieve a VCDX certification?

There have been lots of articles on the defense and the process‚Ķ so I will not waste space on that. This is going to be focused on ‘What is a VCDX?’

It means that you are an expert at designing and architecting VMware virtual environments; more specifically vSphere environments. Of course to achieve this level of certification you had to pass a VCP test, a VMware Certified Advanced Professional Datacenter Design (VCAP-DCD) and Datacenter Administrator (VCAP-DCA) test.

Does it mean you are a master at the technical portions of vSphere (Networking configuration, storage configuration, computer configuration)?


There are VCDX’s that are CCIE level network engineers, but that is not their only skill set. They know of SAN design, layout, configuration, as well of compute limitations.

  • For example they know that a physical server with 4,096TB of RAM, with 64 socket’s is just not realistic or cost effective.
  • They also know that a RAID 5 probably should not be used for a write heavy workload, but if they use a RAID 5 LUN, they identify this possible issue.

Sure it seems easy to install and design a vSphere environment, but consider that vSphere is a technology and suite of products that touches nearly every aspect of a corporations IT.

vSphere requires networking, storage, servers, power, cooling, a workload. This means that you will need to understand enough of those areas, including other areas that you may touch, to properly design the solution.

  • It means that you are able to gather requirements from a customer for their use cases.
  • It means that you are able to consider the impacts of such requirements, product limitations, product features, and most importantly‚Ķ The impact of decisions that you make.
  • It means that you are able to identify the risks in your design, then mitigate or reduce that risk to an acceptable level.
  • It means that you are able to consider dependancies to the elements of your design, the customers existing environment, and the customers existing operational procedures.

You also need to understand the operational aspects of a design.

  • How do I implement it?
  • How do I test it?
  • How can I update it?
  • How do I maintain it?
  • What do I do when something breaks?
  • What is likely to break?

It requires a different mind set.

It requires the mindset of an architect, a consultant, and a system administrator.

How to become a VCDX… Or at least have a less painful defense

I have been asked many times about the VCDX Defense process.  Especially, what to do and what not to do? What is the defense really like? Are the panelists really mean? Do they throw flaming daggers at candidates? and the such… So here are some pointers, tips and other information.

Design Defense

First off, the panelists do NOT have flaming daggers that get thrown at the candidates.  The panelists use soft squishy Nerf balls. Now kidding aside what is a defense like?

You are given 75 minutes to defend the vSphere design that you submitted a few months prior.  During this 75 minutes it is generally okay (and recommended) to give a short 15 minute presentation on your design and who you did the design for.  The key point here is SHORT, do not plan on taking 50 minutes to present your design to the panelists, there are questions and items that the panelists need answered in order to complete the scoring guide.  If you run out of time and do not cover a section (i.e. networking) then the panelists will be unable to give you a score for that section, and your score will suffer.

At end of your slide deck it is very helpful to have all of your Visio diagrams pasted into a few slides, so that they can be referenced as needed during the defense.  Yes the panelists have your application and diagrams in front of them, but it is really handy if you can point to an item on a large screen as opposed to a piece of paper, or waste time recreating the diagram on the whiteboard.

Make sure that the question you are answering is the one asked; if the question is about the technical merits of the storage design, do not answer with something about the logical setup of the storage.

Focus on the question, keep the answers detailed but short so that you can get to more questions and more of the scoring guide filled out.

Remember the panelists did the defense once as well, and just like you the panelists experienced the pain and anxiety, it is fine to be nervous just do not let it become a distraction from your great work.

Before you come into the room to complete your defense you should ask to bring a glass of water or a can of soda (liquor is highly discouraged until after completing the entire defense).  75 minutes of talking can be taxing, so feel free to take sips as needed.  Just remember the clock does not stop for your water breaks.

The design you submitted is scored on both the technical merits and the logical merits of the design.  Just because you can talk circles around the technical aspects, does not mean you will pass; you must be able to talk circles around the logical portions as well.  I will say that again, being an expert in design does not make a VCDX and neither does being an expert in technical troubleshooting.  A VCDX must posses a high level of knowledge, confidence, and the ability to convey both of these attributes.

Break Time

Now you get a 20 minute break… use the break to hit the bathroom, get a new glass of water, and RELAX.  The hardest part is over (well… hardest in my opinion).  Up next are the design scenario and the design troubleshooting.  The panelists at this point have magically transformed into a customer that needs a new design and a design fixed.

Design Scenario

This portion is all about your thought process, the panelists do not expect a completed design or for the solution to the troubleshooting scenario.

The design scenario is 30 minutes of a customer that needs a vSphere design with certain restrictions, contraints, requirements and assumptions.  No, you will not be given all of the information needed, you have to ask for it.  Remember this is about your thought process, and no the panelists can NOT read your mind, so make sure to think aloud.  There is always a whiteboard, feel free to use it.  Fill it up, make pictures, anything to help show your thought process.

The design scenario is scored much like the defense of the design that you submitted.  Make sure that you cover as many topics as you can (technically and logically).

Design Troubleshooting

This section just like the first is just like the previous design scenario.  The panelists want to see and hear your thought process on how to fix the problem.  Anything you want or need the panelists can and will get the information for you, if you need to know the CPU RDY, or WAIT times the panelists have that information.  If you want to know the serial number of the CPU on the 3rd blade server… well the panelists do not have that nor should you need it.

Is there a solution to the design troubleshooting? Yes, there is a solution to the design troubleshooting.  No, you will not be given the answer at the end and you will not find out if you actually solved it.

After that, you get a few minutes to comment on the process, and then you are done.  About a week after the defense you will get an email with your results.

I wish you all good luck!  Remember the panelists are not there to beat you up or throw items at you, all the panelists have been where you are and know the stress you are under.