This guest post was authored by Cisco Designated VIP David Peñaloza Seijas.   


Since I was a kid, I was fascinated by many things I found interesting. I grew up being the nosy kid, or “preguntón,” in Spanish. I was almost always asking “why?” whenever I got something explained or told, which would drive most of the adults to insanity after a couple of hours with me. 

My mom, in an attempt to get this matter solved, gave me a book called “El porqué de las cosas,” which roughly translates to English as “The why of the things.”

CCDE Success Story

I could spend hours reading and asking even more questions. It was an endless loop I enjoyed as a (un)naturally curious kid. To my surprise, the book had several volumes explaining things we all wonder about, but not many of us have the drive to look up, or “to Google,” in today’s parlance. 

Years later I thank my mom for such a brilliant move; I picked up reading in my early years and continued to grow fond of it. Encyclopedias (do any of you remember Microsoft Encarta?), novels (Potterhead here!), stories, newspapers, and my career field: IT. 

I started tweaking my own computer when it felt slow, as I wanted to play the cool games other kids were playing. Over time, it morphed into cracking games, modifying registry keys, disabling/enabling services, troubleshooting problems, and running a shared LAN (Hamachi) to play with my friends — the possibilities were endless! 

Touching and troubleshooting systems, installing devices, and connecting cables and printers (devices from hell!) became natural, and I started making a living out of it when I was 16 years old. It naturally grew into networking, and that’s exactly where my story with Cisco, being it Academy, certifications, forums, all of it! 

As I became a network engineer, the urge to know how things worked just made it enjoyable and compelling. There was an invisible world to us under cables, numbers, and blinking lights. I found an endless curiosity well (or hose) I could drink from every day. 

Why CCDE? 

Around 2016, after several years as a network support engineer, I decided to study network design. But why? By that time, I worked with many engineers and could see a difference between them. Some were happy to implement things and see them working, sometimes without them being completely clear to them. And some other engineers, though, knew very well how things worked and why the changes were being introduced. They had a different perspective.  

That immediately caught my attention; I wanted to know the reasons behind things. I was curious! At that time, the CCDE community was growing and everybody was so vibrant and welcoming that I got lured into it. I decided that even though it would be a hard thing to do, I wanted to study network design. 

You are usually told that CCDE is a certification for experienced engineers and, given the amount of knowledge required, you should have at least one CCIE before attempting it. It initially discouraged me—until I spoke with people like Elaine Lopes, Daniel Dib, Jeremy Filiben, Mark Holm, and Andre Azevedo. They assured me you that don’t need a CCIE to attempt the exam, but you do need the knowledge that comes with it. (Note that all of them have at least one CCIE!)

Like my good friend, Peter Palúch, told me several times: “You must be at the same level. Make technology your second nature, and understand things down to the bone.” 

That year, I started studying and assessing myself honestly, looking for areas to improve. I aimed for CCDE and the vast knowledge it would require.  

I initially took the CCDP* exam to gauge myself, which covered not only fundamentals but also best practices; what was recommended given certain circumstances. After passing, I remember feeling energized and ready for more. 

Back then, I thought: “What if I try the CCDEv2 written exam? 

Narrator:And without realizing, David was setting himself up for a sweet and skin-scorching lesson. 

My Cisco certification exam journey 

It took me three attempts and plenty of studying to pass the CCDE written exam. The first one was my way of gauging myself, while the second failure felt excruciatingly close. Finally, my third attempt was a sweet pass. 

CCDE Success Story

The CCDEv2 written exam was a beast. It mainly combined Enterprise and Service Provider topics, while also adding some security as well, making it a mighty challenging exam on its own. 

Was all my studying enough to pass the written exam? Yes. Barely. 

Was I ready to take the CCDE practical exam? Not really. Not emotionally… and far less technically. But that was a lesson I learned over time after earning myself a couple of scars. 

From August 2017 until May 2018, I studied more, I discussed more, and I thought it was time. I had heard so many things about the exam; the style of the test, the amount of information, the reading and highlighting. It seemed doable. 

Then, my exam day came! There I was in Madrid on May 30, 2018, arriving earlier than anybody else! The testing center wasn’t opened until 10:00, even though the exam was supposed to start at 09:00. Don’t ever ask a Spaniard to wake up early, or you are setting yourself up for failure! 😀 

It was exactly like I had heard—but on steroids! The information, the emails, the diagrams, the questions. I thought I was ready for it, but I wasn’t. The exam made me realize that much more was needed; more knowledge, more reading, more experience. 

Sometimes, that meant that I did not understand a particular technology well enough. Other times, that meant I had missed stated requirements or constraints or was not able to concentrate for the entire time of the test (8 hours). 

This happened twice in 2018, in May and November. On both occasions, it was a FAIL for me. 

CCDE Success Story

After getting beaten twice, I continued trying. In and out, it was tough to get on my feet again. 

In between my attempts in 2018 and 2019, I also took other exams to test my knowledge and get myself closer to the “CCIE-level” knowledge I needed before I faced the beast once more. 

CCDE Success Story

I was able to pass the CCIE R&S** and Service Provider exams while preparing for the next available attempts for the CCDE exam. It felt closer, knowledge-wise, as well as in exam experience. 

In 2019, I went for it again. Twice. Both times, I was visiting Frankfurt. And yes, although it felt better, smoother, and clearer, it wasn’t enough. I failed both attempts that year and thought about taking a break before facing the exam again. I didn’t know, however, that my break would be all that long. 

Taking a break

Between 2019 and 2022, a lot happened in my life. (And probably yours too!) A pandemic, changes in my personal and work life, among other things. I dedicated time to understanding myself (I started visiting a psychologist) to explore what else was inside beyond the technical acumen.  

I was not ready yet, technically and personally. But I wasn’t able to see it. I was too proud to admit it and too stubborn to stop trying. I was only bullying through the attempts and pushing further. 

What would you think after an attempt? 

  • I was not reading fast enough. 
  • I was reading too fast. 
  • I missed the requirements. 
  • I missed that constraint. 
  • Did they say you couldn’t do X? 
  • I must have missed X technology. 
  • I couldn’t stay focused throughout the entire exam. 
  • I brought preconceived notions into the exam. 
  • Nobody does that in the real world! 
  • I should not have second-guessed myself… 
  • God, I hate tables! 

Each one of those attempts teaches you something, but you have to pay attention. Otherwise, it goes over your head, and you end up bumping into the same stone again. Each lesson burns your skin in the process, or at least, that was the feeling for me. Taking the exam was akin to being a meteorite getting closer to the earth: the more you approach it, the mightier the burn and pieces of you continue to fall unless you brace yourself. 

In my case, I was not able to see the forest because of the trees. Although it sounds funny, it was the case. I was looking at a problem instead of zooming out and looking at the big picture with all the moving pieces. 

What else happened during my break? Well, CCDEv2 was revamped to CCDEv3, and topics were adjusted, along with the exam-taking experience. Less Service Provider, and more Enterprise, more Security, more Data Center, more business, more Cloud, and more Wireless! 

Before continuing with my story after the break, we could talk about which things are important for your CCDE journey. Don’t worry. We will be shedding some tears in a bit. 

What do you need to pass the exam? 

Study group and friends – AKA community 

Your study group could be the key resource you need to pass. The more perspectives you get, the better your technical arsenal will be when facing the exam.  

During my CCDE journey, I had the luxury of studying with people like Mike McPhee, Jason Beltrame, Bruno Wollman, Fareed Fakoor, Remington Loose, Ronald Lopez, Anti Sourdi, Freerk Terpstra, Nicolas Vallet and Fabian Beck. All of them are brilliant engineers/architects, and they all taught me something along the way. We shared tips and knowledge, had sessions to teach others about what we were good at, and of course, made beautiful bonds in the process. 

On top of that, I had wonderful friends who were not studying to take the CCDE exam but were supporting me and teaching me things (teach me your secrets, master!) or supporting me as a person, as a friend: people like Peter Paluch, Daniel Dib, Mark Holm, Martin Novak, Ivan Zlatkov, David Chapcak, Matt Saunders, Kurt Claes, Peter Haluska, and Martin Duggan. 

A group of friends and study buddies, people to discuss with, people willing to listen, a floor that could support me… a community. Without them, I would not have passed it. This late success was thanks to them for their unwavering support and motivation. It is as much mine as it is theirs. 

Every time I felt like quitting (especially the last two attempts) I was supported by them. (Special mention to Peter, Daniel, Kurt, and Mark!) By people who, at least at that moment, believed in me more than I did. They kept me on track, pulled my ears when needed, and hugged me hard enough to pull my pieces together again when I couldn’t do it myself. 

Know yourself 

Another important part of your journey is to know yourself. This might sound like a cliché for many, but it is tremendously important, or at least it was for me. 

The CCDE exam is different from any other CCIE exam. It does not rely on muscle memory or fast typing. You must consider each option, read every document, and think of every choice. It is an 8-hour-long reading comprehension exam with technical and business topics. Your mental state is paramount. 

  • Do you know when you study the best? Is it during the morning, afternoon, or night? 
  • How fast can you read? 
  • How much of that can you retain? 
  • Can you handle eight hours of studying? 
  • What about 4-hour or 2-hour blocks? 
  • How good is your concentration? (I get distracted easily.) 
  • How do you cope with anxiety? 
  • How do you calm your nerves? 
  • Are you into meditation? Or do you do a quick series of 20 pushups and feel like new and focused? 
  • What about your feelings about the exam? 
  • How do you feel when entering, leaving, and during the exam? 
  • Anxious? 
  • Nervous? 
  • Scared? 
  • Relaxed? 

All these things were important for me, and I wish I would have thought about them beforehand. I had to learn to consider them after every failed attempt. 

Initially, my drivers when I started all this were: ambition, pride (rather hubris), and fear. I wanted to get as high as possible, to be really good at something, to be recognized, to shut up every mouth that said (there were many) that I couldn’t make it or it was too hard and I was going to fail, and also, my fear of missing out (FOMO). 

A wonderful song about this is Vienna, by Billy Joel. 

Over the years I learned (thanks to my dear friend Peter Palúch, my psychologist, and a ridiculous amount of introspection) that although my previous drivers helped me to stay motivated and leave the country, I was not going to make it any further with negative emotions, they would chew me up eventually. What would be better? Finding positive motivation! 

I did my best to stop comparing myself with others and only compare myself with David from the past. We all have failures, we all know something somebody else doesn’t, and we all can learn something from others. Even the people we don’t like can teach us something. 

I started looking at the journey as well as the goal. I did not stop chasing the sun, but I started to enjoy the view while I was doing it. I also started to appreciate more of what I was doing, what I was learning, and what I was making, instead of thinking, “I won’t have enough time in my life to do all the things I want to do; I must go faster.” 

Lastly, and the hardest one: I did my best to stop worrying about the exam’s outcome. After all, I had already failed several times. Will it burn more? Maybe a bit. Will it be a catastrophe? Not really. Just pick up your pieces, regroup, and tackle it again. The exam is already stressful enough, and worrying about failing before taking it will only make me feel more anxious.  

Don’t beat yourself up beforehand. Give yourself a chance, forgive yourself, and be kind to yourself. We all make mistakes. Trust me, you are enough. You can do it. You have it in you. 

During my last attempt, I was focused on the exam itself, and the night before I thought: Well, whatever happens, I will give my best during the exam. Pass or fail, it will be the best of me.

I did not know if I passed, and I was about to check the next available date for the exam. Little did I know that I would pass this time, but more on that later.  

Narrator: And then David ugly cried for hours because he was a llorón when he knew he passed. 

Back on track 

After the break, I was back on square one: the exam was revamped to version 3. Its contents had changed, and my written exam (valid for three years) had already expired. 

What was the first thing to do? Take the written exam again! I was lucky enough to have a last chance before the CCDEv2 written exam would be retired on November 1, 2021. 

I brushed up on all the topics and studied for some weeks before feeling ready and, of course, having the looming shadow of the soon-to-be-retired exam over my head. To my luck, I passed, once again with a sweet 860. I cannot lie about this: it was glorious. 

I earned the right to take the practical exam again, but it was a new version. The exam topics were the first step to take. I had new things to learn: Wireless, Cloud, and Security. And also others to brush up and finally learn well: QoS, and multicast. 

Now, the exam was offered in Brussels like any other CCIE exam, so I did not have to juggle balls to book an exam in a Pearson Professional Center in Frankfurt or Madrid. I could visit the Cisco office in Brussels like everybody else! 

Also, several friends work there, so it is a familiar place for me. 

CCDE Success Story

In the course of ten months, I visited Brussels four times. Every time, I was welcomed by my dear friend Peter Palúch and supported till no end by him and Kurt Claes. 

My first attempt was an exploratory one. I had absolutely no hopes of passing. I had to see what was different: the new engine, the new scenarios, the style, the technology. And, God, I did. 

I came out of the exam looking like a fish in a refrigerator: eyes and mouth wide open, but I could not see or say anything. So many new things to catch up with, more tech, more business, and the testing engine was cooler and easier to use. (Not everything was negative!) 

I spent plenty of time learning about Wireless, one of the weakest areas in my technical acumen. Freerk Terpstra and Fabian Beck gave me a masterclass on many things, they explained details, deployments, authentication, and the nature of wireless networks, it was intense! Freerk even created a mini CCDE scenario and explained it to us in detail. 

I went again in February with plenty of hopes, however, it wasn’t yet my time. Even though I felt better, more confident, and happier with my performance, it wasn’t enough. I realized I needed more cloud, more migrations, more business acumen, more reading skills, and more concentration. It was an endless list! 

I kept a list of topics I felt unsure about and added more after every attempt. The list started huge and continued to shrink over time while I addressed more topics—until the last attempt. 

For the June attempt, I put plenty of effort into studying. My Cisco Live US session catalog was all about things I needed for the exam, including a CCDE techtorial with Mark Holm, Zig Zsiga, and Rick Bauer, and several sessions about design. 

There I was in the CCDE Techtorial: “Dude, don’t tell me this bull****, I already took the exam!” (I am sorry, Mark.) 

I wasn’t making any friends during that session. Turns out that some discussions aren’t about absolutes or sides, they rather fall into a gray area right in the middle, and there are several shades of gray to deal with. Some assumptions are fair, but too much of that trips you off. You end up walking on a tightrope like a circus performer while the drums resonate in the background. 

I felt confident and proud. I did my best and felt ready for the exam. Right after Cisco Live US, I headed back to Brussels for my third attempt at CCDEv3. 

I worked on my knowledge, note-taking, reading, and concentration and discussed with the already-certified CCDE folks I knew. I felt ready. This was my time. I was excited while taking the exam. It felt good, it felt like a breeze, and I was almost sure. 

I came out hoping for the best and was shot down by a FAIL. It was, by far, the most painful of the attempts. I felt lost, that I did not know what to work on anymore, and that I was not able to conquer such a titanic goal after so long. My scores were showing some improvement after every attempt, and yet, I failed again and was terribly confused. 

It took me several days to even process so many things and handle my feelings. And when I was about to throw the towel, my friends were there for me. Once again, they held me up, they assured me I was close, and they gave me more encouragement than I could have asked for. 

I felt like Spiderman (Tobey Maguire) getting carried over their heads after saving the people on the train from an imminent crash. But this time, I was the one being saved, as well as carried. 

The last straw 

With their help, I was still a bit hesitant, but I picked up my pieces and tried to do something different for the October attempt. 

Was it about knowledge? What else was I doing during the exam? At some point, once you deal with the knowledge gaps (or you think you did), you have to worry about your exam-taking experience and strategy. 

I worked more on my concentration and on exercises to keep myself active. I brought plenty of sweets, caffeine, and water and did many, many pushups during the test. 

Every time I felt my mind was slipping away from me, I would step up, do 20 pushups, stretch myself, wash my face, and come back to my seat. 

During the exam, I was consuming energy drinks, water, coffee, sourworms, and Nutella biscuits. I was glad I could bring these things to the testing room! 

I also offered from my arsenal to all the people taking the exam with me. Most of them responded to my proposal with incredulous looks and awkward silence. But a couple of them did get closer. They got Nutella crackers and an energy drink, some chocolates. 

This time my attitude wasn’t about passing the exam. It was about enjoying the ride, doing my best, and feeling proud of how far I’ve come. 

This time I did not feel anxiety crawling over my shoulder during the exam, worrying about the result. I was focused, entertained, and positive, all about enjoying myself while it happened. 

This time the anxiety wasn’t in the driver’s seat. I felt fine, I felt calm (despite the irresponsible amount of caffeine and sugar in my system), and I felt present.  

There I was, telling Peter how it was, how I felt, what I saw. I wasn’t sure if I passed, but I did my best, and I was proud of it. I checked the results sometime after while sitting next to my friends. In the beginning, I couldn’t believe it, I thought the website was broken, and I could not see the typical “FAIL” I was expecting. 

I thought: “This is kaput, where is my fail?

I continued to search the bottom right side of the screen. 

And there it was, at the top left of the screen. It wasn’t broken. It wasn’t wrong. I really passed, everything was all right. 

It was the end of an era, the closure I so much craved for. I could not do anything else but cry. I was always enough, I was always ready, and the journey finally made sense.  

CCDE was and will be, for me, the most successful set of failures I have ever encountered. And I am proud of it, like the quote attributed to Thomas A. Edison:

I have not failed. I’ve just found 10,000 ways that won’t work.

—Thomas A. Edison


Exclusive: David reveals the key moments and mindset that led to his CCDE certification victory on the Cisco Learning Network Podcast.

Listen to the episode now:





*The Cisco Certified Design Professional (CCDP) certification was retired from the Cisco Certification program on February 23, 2020.

**The CCIE R&S, or Routing and Switching certification, migrated to the CCIE Enterprise Infrastructure certification on February 23, 2020.


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