VCAP-DCD Part 2: First Attempt – Lessons Learned

By | April 30, 2014


Last Thursday I made my first attempt at the VMware Certified Advanced Professional – Data Center Design 5 exam. I failed, scoring 285. 15 less than the required 300. After taking some time to decompress and reflect on the experience I am ready to discuss the good, the bad, and the ugly. I feel I have a much better understanding of what is required to pass and plan to when I retake the exam in two weeks. My hope is that the community can learn from my mistakes and better prepare for this challenge.

The Test

Everything you have heard or read is true. Well, mostly true at least. This is bar none the hardest test I have taken in my life. That includes the SAT, college exams, the CCIE written test, and every other certification test. The amount of knowledge and skill required is very high both technically and from a business perspective. Time is also a serious factor, however not as much as I think it is on the VCAP-DCA. You must work quickly. I clicked finish with just under 3 minutes on the clock.

I’ve heard folks say that if you do vSphere design for your day job the test is not that bad. I disagree with that statement. Yes, you must know design well, but the VCAP-DCD is brutally technical. You are required to know compute, storage, and networking (as they relate to vSphere) in a very broad and very deep way. If you are thinking about sitting the exam take an honest assessment of you technical skills.  If you don’t believe them to be rock solid, keep reading. I found a great measure to be watching past VMworld deep dive sessions. When you find yourself thinking “Ugh, this stuff again? ” because you’ve heard it a hundred times and could present the session, you are ready.

Ok, so if you think you have the technical table stakes for this test it is time to focus on design. This is a completely different skill set and equally as important for success. I can’t stress enough that you must understand Requirements, Constraints, Assumptions, and Risks. If you don’t you are guaranteed to fail. There are several great resources for design. I recommend:

Pluralsight – Designing VMware Infrastructure by Scott Lowe

VMware vSphere Design 2nd Edition by Forbes Guthrie, Scott Lowe, and Kendrick Coleman

CloudXC – Josh Odger’s Blog

vcdx133 – Rene Van Den Bedem’s Blog

Zachman International – Enterprise Architecture

The Questions

There are three types of questions on the exam, Multiple Choice, Drag and Drop, and Design. I’ll cover each separately.

Multiple Choice

There are 80 or so multiple choice questions worth 4 points each. Most of these require at least two or more answers. This is where you will be asked very deep technical questions. You should know the majority of these. The text is not long and they are mostly rote knowledge based. Expect topics like Permissions, SAN Zoning, Required Ports, Sizing, Performance, and several others.

Fair warning: I have working with Windows professionally since NT 3.51. There were a couple of questions about things I’ve never heard of. Ever.

Drag and Drop

There are 15 Drag and Drop questions worth 10 points each. They all involve matching a items in list A to list B. Some or all of each list may be used. Some or all maybe be used more than once, depending on the question. These range from easy to brutally hard. Most are the later. There is also a scenario button. Click it every time. It may provide additional detail. Most questions don’t tell you this. I did not and in retrospect it probably would have clarified some extremely confusing questions. This is also where you will find case studies. Read them quickly. Most of the information is not important or worse, contains red herrings. Find what you need. You should know when you see it.


There are 5-6 Design questions worth 33 points on average. Some are worth more than others and partial credit counts. I had six. Two were simple. Three were tedious and involved but not terribly hard. One was vague to the point of ridiculousness. The tool used for these questions has been called “Visio-like”. This is flat wrong. There are pictures connected with lines. That is the end of the similarities. Take the simulator. The tool is not hard to use, but it is not intuitive. You have a limited set of object choices and may not have one you think you need (hint: if that happens you were probably wrong anyway). It also contains objects not mentioned anywhere in the question. You may or may not need these. Do your best. Spend 15 minutes on each and move on. Try not to over think it or assume to much. I think I assumed too much a couple of times.

A Note on Vagueness

There are several questions that may seem vague. This is for one of three reasons:

1. It is intentional. If the question is reporting on stakeholder interviews it is up to you to extract the real meaning. This is true on a couple of other scenarios.

2. You are not prepared. It is possible that you don’t have the required knowledge to understand the question. If the question is technical this is most likely the case. Write down the topic on your “whiteboard”, take a mental snapshot and study the topic later.

3. Like me you failed to click the scenario button in a drag and drop. Click the button and the truth shall be revealed.

Thoughts on Failure, Pride, and the Community

When I saw the message that I had failed I had two thoughts, first anger that I was so close, followed by shame. I felt that I had let myself down as well as the vCommunity. I was anxious about tweeting my result as so many folks who had helped me were waiting to hear how I did. I felt like I had let down everyone who believed in me and said “I know you’ll nail it!”

Those thoughts are complete bullshit. When I sucked up my pride and cowardice and tweeted the results support flooded in. So many people offered advice and help to get where to I needed to be. Since then I have spoken to several VCDXs, VCDX candidates, and folks who have the VCAP-DCD. Almost all of them failed the first time. I won’t call anyone out, but some extremely smart VCDXs, who I would consider pillars of the vCommunity as well as personal role models, failed the first time. It is OK. I honestly assessed my shortcomings and hit the books again to learn. Apparently this is how you grow as a person.

To give you an idea for the numbers around this test, I’ve heard from a couple folks that around 800 or so people have passed it, less than 400 in the Americas, and the failure rate is staggeringly high. This is not official and I can not back it up, but I believe it to be true.

The important thing is that in preparing for the exam I have become shockingly better at what I do. By an order of magnitude. I have also learned that while my knowledge is vast and deep, it is nothing compared to what I have yet to learn. I have come so far and have so far to go.