Kubernetes Pod stuck in CrashLoopBackOff

Question

Dockerfile

FROM ubuntu
MAINTAINER [email protected]
RUN apt-get update
RUN apt-get install -y openjdk-8-jdk
ADD build/libs/micro-service-gradle-0.0.1-SNAPSHOT.jar /var/local/
ENTRYPOINT exec java $JAVA_OPTS \
 -jar /var/local/micro-service-gradle-0.0.1-SNAPSHOT.jar
EXPOSE 8080

deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: micro-service-gradle
  labels:
    app: micro-service-gradle
spec:
  replicas: 1
  selector:
    matchLabels:
      app: micro-service-gradle
  template:
    metadata:
      labels:
        app: micro-service-gradle
    spec:
      containers:
      - name: micro-service-gradle
        image: micro-service-gradle:latest
        ports:
        - containerPort: 8080

Deploying spring boot application in Kubernetes . Pod is not getting created. When i check kubectl get pods. it says CrashLoopBackOff.

NAME                                  READY   STATUS             RESTARTS   AGE
micro-service-gradle-fc97c97b-8hwhg   0/1     CrashLoopBackOff   6          6m23s

I tried to check logs for the same container. Logs are empty

kubectl logs -p micro-service-gradle-fc97c97b-8hwhg

I created the container manually using docker run. There is no issues in image and containers works fine.

How to verify the logs for why the pods in crash status.

Answer 1

You need to use

kubectl describe pod micro-service-gradle-fc97c97b-8hwhg

to get the relevant logs. This should guide you to your problem.

Answer 2

I ran into a similar issue. When I run

kubectl describe pod <podname>

and read the events, Though the image was pulled, message outputted was 'restarting failed container' The pod was crashing because it was not performing any task. To keep it running, I add a sleep command based on similar example in the docs

  command: ['sh', '-c', 'echo The app is running! && sleep 3600']

This SO answer also mentions running an infinite could also solve the problem https://stackoverflow.com/a/55610769/7128032