DevOps Classroom notes 25/Jan/2024

YAML

• Refer Here for YAML and Json tutorial

Writing k8s manifests

• When we write manifest we interact with api server using kubectl
• kube API Server exposes k8s resources as REST API’s
• kuberentes api versioning: Refer Here
  • apigroup: this is grouping by k8s for versioning
  • version:
• every k8s resource which we create we need to write apiVersion

# rule
apiVersion: <group>/<version>

# if the group is core
apiVersion: <version>

• api reference Refer Here
• 1.29 api reference Refer Here

Activity 1: lets create an httpd pod manifest

• Docker image information
  • image: httpd:2.4
  • port: 80
• Lets write manifest:

---
apiVersion: v1
kind: Pod
metadata:
  name: httpd-pod
spec:
  containers:
    - name: httpd
      image: httpd:2.4
      ports:
        - containerPort: 80
          protocol: "TCP"

Activity 2: Create a Pod with two containers

• Create a pod with two httpd containers

---
apiVersion: v1
kind: Pod
metadata:
  name: httpd-twice
spec:
  containers:
    - name: httpd1
      image: httpd:2.4
      ports:
        - containerPort: 80
    - name: httpd2
      image: httpd:2.4
      ports:
        - containerPort: 80

• Two contianer in the Pod should not be using the same port