The CKAD browser terminal
This is a general overview of what helped me to prepare for and pass the CKAD as well as how to best handle the browser terminal.
This is what the setup will (or could) look like. On the left you see the questions and time, on the right you have one terminal. You can configure it to have two screens using tmux. Read further to see how I did set it up.
Lagging
The lagging wasn’t too bad, definitely make sure you are using a good internet connection because your webcam and screen are uploading all the time!
Copy&Paste
I had sometimes issues copying text (like pod names) from the left task information, I had to “hard” hit Cmd+C a few times to take action. Apart from that copy&paste was just working fine, just like in normal terminals (can only tell for Mac).
Notebook
You have access to a notebook which I used to write down the questions I skipped. I did skip two 2% questions and one 3% question. The 3% question I still managed to jump back to and solve at the very end. I didn’t do the two 2% questions which was probably good for saving time.
Knowledge
Study all topics as proposed in the handbook till you feel comfortable with everyone.
Do all of these, maybe 2–3 times: https://github.com/dgkanatsios/CKAD-exercises
I started a series with scenarios here on Medium, do all of these. Also imagine and create your own ones.
Are you ready?
Put your knowledge to the test with the CKAD simulator I developed. Learn with real scenarios and in a very close-to-real environment.
Your Desktop and Applications
You are allowed to have one monitor connected. I used my MacBook with lid closed and one 28" external monitor, external mouse+keyboard and external webcam+microphone.
Having a large screen definitely helps as you’re only allowed one application open (Chrome Browser) with two tabs, one terminal and one k8s docs.
You have to be able to move your webcam around in the beginning to show your whole room and desktop. Have a clean desk with only the necessary on it! You can have a glass with water without anything printed on.
Bash Aliases
First thing when I got access to the terminal I did define aliases:
vim ~/.bashrc# then add those two:
alias k=kubectlalias kn='kubectl config set-context --current --namespace '
The second one allows you to set the default namespace of your current context simply with kn np1 (where np1 is the namespace name) and back to default with kn default. You have to solve many tasks in different namespaces.
The command for switching to the correct context will always be printed in the left sidebar, so you can just copy and paste it.
Vim Master
configure vim once logged in
Also directly at the beginning I did setup vim for good yaml editing:
vi ~/.vimrc# then add these two lines to the file
set tabstop=2
set expandtab # use spaces for tabs
toggle vim line numbers
When in vim you can press Esc and type :set number or :set nonumber + Enter to toggle line numbers. This can be useful when finding syntax errors based on line but can be bad when wanting to mark© with mouse. You can also just jump to a line number with Esc :22 + Enter.
use vim copy&paste
Get used to these copy&paste commands:
Mark lines: Esc+V (then arrow keys)
Copy marked lines: y
Cut marked lines: d
Past lines: p or PGeneral Linux Console Stuff
Background tasks
If a task, like deleting k8s objects, takes some time but you need to edit a yaml directly after, like:
kubectl -f delete stuff.yaml # takes some precious time...
vim stuff.yamlInstead of waiting for the deletion to finish you could use Strg+Z to push a task in the back:
kubectl -f delete stuff.yaml # now press Strg+Z
vim stuff.yaml
To retrieve a background task you just type the command fg (for foreground).
Tmux Master
It’s mentioned in the handbook that you can use tmux. You only have one terminal during the exam in the browser, so it’s nice to know some useful tmux tricks.
BUT only use it if you are comfortable using it because copy&paste as well as scrolling might be different.
Get familiar with tmux for splitting screens and run multi processes simultaneously. Here are the commands I use with tmux.
Always enter CTRL B followed by one of these commands:
Split screen horizontally: “
Select screen: Arrow-Keys
Toggle layouts: space
Swap panes: { and }
Detach session: d
List/Select windows: w (left right arrows to select panes)
Attach existing session
If you detached tmux you can resume sessions again.
List existing sessions: tmux ls
Attach to last session: tmux aDocumentation
Read the Handbook
Read the important tips
https://training.linuxfoundation.org/wp-content/uploads/2019/05/Important-Tips-CKA-CKAD-4.30.19.pdf
Get familiar with the Kubernetes documentation.
You can have one browser tab open with these links, no others:
Recap
That’s from me. You have any other tips? Good luck!
More?
More tips and scenarios on the CKAD simulator at https://killer.sh
