I recently sat for the Certified Kubernetes Application Developer (CKAD) exam. And as someone who has taken over 10 certification exams (read more on the strategies I use to pass exams), the CKAD was the first exam to throw a wrench into my strategies and affect my “during the exam” confidence. That’s what motivated me to write these microblog posts about things I wish I knew going into the exam.
There’ll be a total of three posts over this coming week, so make sure you check back regularly for the next tip!
Without further ado —
What I wish I knew before I took the CKAD: Multi-what?
There’s a time period before the CKAD, and after the CKAD. Pre-CKAD and Post-CKAD, if you will. Before the CKAD, I was a fervent typer in the terminal, quick to use all the shortcuts I knew to enable the quickest workflows possible. Opening up new terminal windows and snapping the terminal to the side of my screen, resizing it, adjusting it to be exquisitely perfect. After the CKAD? Why bother with that many keystrokes? Just open up tmux and split my pane horizontally, and voila, kubectl explain on one screen, my main kubectl window on the other.
It’s important to note that the CNCF tips for the CKA and CKAD are even “pro-multiplexer”! They state that:
“Only a single terminal console is available during the exam. Terminal multiplexers such as GNU Screen and tmux can be used to create virtual consoles.”
With the ability to split terminal panes into separate panes, it is possible to have an easy reference for YAML construction/modification and then use another pane for creating the actual YAML. Use it and abuse it to your heart’s desire when you get into the exam, echoing the following command to make sure it sources the .bashrc profile. This is important for the next tip we’ll cover regarding your shell environment during the exam.
echo '[[ -f ~/.bashrc ]] && . ~/.bashrc' >> ~/.profile
I’m not going to cover how to use tmux, as that would be against this micro-blog’s philosophy (hopefully micro is implicit enough). However, these commands should be enough to get you started:
- Linux –
sudo {apt,yum} install tmux
- Mac –
brew install tmux
- Mac –
tmux
(starts the multiplexer)- Ctrl+b (don’t press anything else after this keystroke)
- Shift+”
In short order, Ctrl+b suspends interacting with the terminal pane, allowing you to interact with tmux. Shift+” splits your terminal pane horizontally. To navigate between the two, or any pane, suspend the terminal environment (Ctrl+b), and press and arrow key of your choice.
In our next microblog, we’ll cover how to quickly set up your shell environment when you start the exam.