I have a Spring Boot app running with Spring Actuator enabled. I am using the Spring Actuator health endpoint to serve as the readiness and liveliness checks. All works fine with a single replica. When I scale out to 2 replicas both pods crash. They both fail readiness checks and end up in an endless destroy/re-create loop. If I scale them back in to 1 replica the cluster recovers and the Spring Boot app becomes available. Any ideas what might be causing this issue?

Here is the deployment config (the context root of the Spring Boot app is /dept):

apiVersion: apps/v1
kind: Deployment
metadata:
  name: gl-dept-deployment
  labels:
    app: gl-dept
spec:
  replicas: 1
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxUnavailable: 1
      maxSurge: 1
  selector:
    matchLabels:
      app: gl-dept
  template:
    metadata:
      labels:
        app: gl-dept
    spec:
      containers:
      - name: gl-dept
        image: zmad5306/gl-dept:latest
        imagePullPolicy: Always
        ports:
        - containerPort: 8080
        livenessProbe:
          httpGet:
            path: /dept/actuator/health
            port: 8080
          initialDelaySeconds: 15
          periodSeconds: 10
          timeoutSeconds: 10
          successThreshold: 1
          failureThreshold: 5
        readinessProbe:
          httpGet:
            path: /dept/actuator/health
            port: 8080
          initialDelaySeconds: 15
          periodSeconds: 10
          timeoutSeconds: 10
          successThreshold: 1
          failureThreshold: 5