[k8s] Deployment & replicas

kubia.yaml

• https://kubernetes.io/ko/docs/concepts/workloads/controllers/deployment/

apiVersion: apps/v1
kind: Deployment
metadata:
  name: kubia
spec:
  replicas: 3
  selector:
    matchLabels:
      app: kubia
  template:
    metadata:
      labels:
        app: kubia
    spec:
      containers:
        - name: kubia
          image: seunggab/kubia:latest
          ports:
          - containerPort: 8080

shell

• https://minikube.sigs.k8s.io/docs/handbook/accessing/#using-minikube-tunnel

kubectl apply -f kubia.yaml
kubectl expose deployment kubia --type=LoadBalancer --port 8080 --name kubia-http

minikube tunnel &

curl 127.0.0.1:8080

---

if you change replicas

1. change kubia.yaml (3 -> 5)

apiVersion: apps/v1
kind: Deployment
metadata:
  name: kubia
spec:
  replicas: 5
  selector:
    matchLabels:
      app: kubia
  template:
    metadata:
      labels:
        app: kubia
    spec:
      containers:
        - name: kubia
          image: seunggab/kubia:latest
          ports:
          - containerPort: 8080

1. re-apply

kubectl apply -f kubia.yaml

# as-is
NAME                     READY   STATUS    RESTARTS   AGE
kubia-5f896dc5d5-qp7wl   1/1     Running   0          20s
kubia-5f896dc5d5-rqqm5   1/1     Running   0          20s
kubia-5f896dc5d5-vqgj9   1/1     Running   0          20s

# to-be
NAME                     READY   STATUS              RESTARTS   AGE
kubia-5f896dc5d5-fsd49   0/1     ContainerCreating   0          6s
kubia-5f896dc5d5-qp7wl   1/1     Running             0          3m35s
kubia-5f896dc5d5-rqqm5   1/1     Running             0          3m35s
kubia-5f896dc5d5-vqgj9   1/1     Running             0          3m35s
kubia-5f896dc5d5-x84fr   1/1     Running             0          6s

• ref: https://github.com/seunggabi/kubernetes-in-action/wiki/2.-Kubernetes

https://stackoverflow.com/questions/64306744/error-when-trying-to-expose-a-docker-container-in-minikube

Error when trying to expose a docker container in minikube