KB for CKA exam

Table of Contents

1. Imperative
   • Pods
   • Nodes
2. Declarative
   • Creating Pods
   • Controllers and Services
3. Templates
4. Acknowledgements

Imperative

Imperative way to run commands with kubectl.

Pods

• List pods showing their labels

kubectl get pod --show-labels

• List pods with specific label

kubectl get pod -owide --selector=$label

Nodes

• Remove default taint from master nodes

kubectl taint nodes --all node-role.kubernetes.io/master-

• Add taint to a node

kubectl taint nodes node1 key1=value1:NoSchedule

Declarative

Declarative way to create, modify objects or anything in k8s.

Creating Pods

• Create pod with taint toleration

apiVersion: v1
kind: Pod
metadata:
  name: nginx
  labels:
    env: test
spec:
  containers:
  - name: nginx
    image: nginx
    imagePullPolicy: IfNotPresent
  tolerations:
  - key: "example-key"
    operator: "Equals"
    value: "example-value"
    effect: "NoSchedule"

• Create deployment with NodeAffinity

apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    app: nginx
  name: nginx
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nginx
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: nginx
    spec:
      affinity:
        nodeAffinity:
          requiredDuringSchedulingIgnoredDuringExecution:
            nodeSelectorTerms:
            - matchExpressions:
              - key: disktype
                operator: In
                values:
                - ssd
      containers:
      - image: nginx
        name: nginx
        resources: {}
status: {}

Controllers and Services

Templates

Please contribute using the templates below.

• Showing files

Please ...First line
...Second line
paste the file content here

• One line commands

this is an example command

• Step-by-steps

1. Get a free API Key at https://example.com
2. Clone the repo

   git clone https://github.com/your_username_/Project-Name.git

3. Install NPM packages

   npm install

4. Enter your API in config.js

   const API_KEY = 'ENTER YOUR API';

Acknowledgements

• Kubernetes Documentation
• CKA exam description