Monday 25 May 2020

Study Resources for Learning Docker and Passing the Docker Certified Associate (DCA) Certification

On the 23rd of March, the UK Government announced we would be entering “lock down” for the foreseeable future, with no real end date given. My role within Microsoft usually means that I’m travelling at least 3-4 times per month, with no trips possible due to lock down I decided that it was an opportunity to really study hard and skill up in some of my weaker areas.

This helped me define my study plan for the rest of 2020, for me having a study plan aligned to getting certifications makes sense. The formality of having an exam booked with a syllabus of content to learn has always helped me keep on track. This is my justification for chasing certifications instead of “actual skills” even though the two overlap.

For the rest of 2020 I have set myself the goal of getting the following certifications:

  •     Docker Certified Associate (DCA)
  •     Linux Foundation Certified Systems Administrator (LFCS)
  •     Certified Kubernetes Administrator (CKA)
  •     Microsoft Azure Certified DevOps Expert (AZ-400)
The entire Containers and DevOps ecosystem has always interested me, it is also a critical area for my role as a Cloud Solution Architect with a focus on applications & infrastructure.

The first step was to get the Docker Certified Associate out of the way, which is what I am going to cover in this post. Docker was the obvious choice to start with in the journey to get deeper skills in the Container and DevOps ecosystem. Docker has become the industry leading container engine, with it being the default engine which is shipped with Kubernetes.

The Docker Certified Associate (DCA) certification is the only professional certification offered to cover Docker Inc and their technology. It is a multiple-choice exam with some new DOMC questions, delivered remotely which consists of 55 questions which must be answered in a 90-minute period. The DOMC questions are weird, I would use the following simulator to get an idea of what to expect before you go into the exam (link at bottom of page). Full details can be found here

The following resources are what I used to get up to speed enough with Docker to pass the certification exam.

Video Training

The courses listed below are the ones in which I used before the exam. I took them in this order and learned something new from each of them. Many of the courses have overlapping content but that is not a bad thing when learning something new.

Pluralsight (Nigel Poulton)
Good intro course which covers many of the basics around containers and container orchestration. If you have some experience with containers you can probably skip this one, but I found it useful.

Pluralsight (Nigel Poulton)
Great course which was key for me to build that first level of formal knowledge around Docker. Not to be missed unless you have some production experience with Docker.

Pluralsight (Nigel Poulton)
Do this course if you have no other choice from the Pluralsight library. It is the most complete and well rounded of the courses and will put you in a good place to go deep with Docker. However, it does not cover all the areas of the DCA and will not make you exam ready alone.

Pluralsight (Nigel Poulton)
Short and sweet but to the point and covers loads of good detail on how networking in Docker works.

Pluralsight (Elton Stoneman)

Excellent course if you have some time before the exam to go deeper with Swarm. I did it to bridge some gaps but after passing the exam I do not plan to do much with Swarm as Kubernetes is the orchestrator of choice at work.

Udemy (Brett Fisher)

This is also an excellent course. I only did half of it which covered the Docker content but intend on going through the Kubernetes sections as well. This course does assume some knowledge but will help massively in getting prepared for the DCA. Brett does state this is not an exam prep course so other study is required to round off the areas this brushes over.
Linux Academy (William Boyd)
This is unmissable in the weeks before the DCA exam. It is very exam focused which none of the course above are. It covers off all the points on the DCA syllabus.

Linux Academy (Travis Thomsen)
Again don’t’ go into the exam without having watched this course. I skipped some of the earlier videos and went to my weak areas to ensure I filled the gaps. Highlight recommended. It is very fast paced so if you are building your own study plan do this course towards the end.

Linux Academy (Travis Thomsen)
Very good resource to help build the hands-on skills needed to be confident with Docker. I did this two days before the exam.

All the video content listed above is worthwhile and absolutely worth your time if you plan to sit the Docker Certified Associate (DCA) exam. I must say that Linux Academy stood out from the rest, probably because they provide hands on labs.

Reading Material

To supplement the video training, I also used the following resources:

The Docker Deep Dive Book – Nigel Poulton

This is an excellent book not only for study but for general reference as well. Just buy it and read it. It is on Amazon for less than a tenner. I also printed the exam blueprint and used it to cross check exam topics with the contents of this book. Not to be missed. I think the technical diagrams in this book are what stands out they are could even make it into design documents in some cases.

Docker Reference Architecture – Docker Inc

I read most of the relevant architectures a couple of times and did one last scan the day of the exam.

Docker Study Guide – Evgeny Shmarnev

This is a collection of Docker documentation which links to the exam content. I used it extensively and it was helpful.

Practice Exams

Practice exams are mandatory before sitting a certification in my experience. I used the following ones.

Linux Academy – offer practice exams as part of the courses.

Whiz Labs – Docker Certified Associate Practice Tests

Example Questions for DCA

Ref 1: (DOMC questions)