When I run "kubectl apply -f {manifest}", RollingUpdate does not work

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1

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Cluster information:

Kubernetes version:
Client Version: v1.25.4
Kustomize Version: v4.5.7
Server Version: v1.25.4

Cloud being used: AWS

Installation method: kOps

Host OS: Ubuntu

CNI and version: 3.24.5
CRI and version: 1.6.10

Question:

My Rolling Update strategy setting goes well when do “kubectl rollout restart {deployment name}”. However, when I run “kubectl apply -f {this manifest}”, RollingUpdate does not work and it causes termination and creation of all pods immediately, on the same timing. It prevent my system from no-interruption. any advice?

Manifest:

---

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    run: web
  name: web
  namespace: default
spec:
  replicas: 3
  revisionHistoryLimit: 1
  selector:
    matchLabels:
      app: web
  strategy:
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
    type: RollingUpdate
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: web
    spec:
      imagePullSecrets:
      - name: docker-hub-secret
      initContainers:
        - name: check-init-flag
          image: busybox
          command: ["/bin/sh", "-c"]
          args:
          - |
            if [ ! -f /etc/host/sync/init_flag ]; then
              echo "ERR: $(date -u -d '+9 hours') $(hostname) init_flag not found." >> /var/persistent/log/init_error.log
              exit 1
            fi
          volumeMounts:
            - name: persistent-storage01
              mountPath: "/var/persistent/"
            - name: host-etc
              mountPath: "/etc/host/"
      containers:
        - name: web
          image: repo/example:web3
          resources:
            requests:
              cpu: "350m"
            limits:
              cpu: "900m"
          command: ["/usr/bin/bash", "-c"]
          args:
          - |
            cp -pr /var/persistent/k8s/web/00_entrypoint.sh /entrypoint.sh
            exec /entrypoint.sh
          lifecycle:
            postStart:
              exec:
                command: ["/usr/bin/bash", "-c", "/var/persistent/k8s/web/01_poststart.sh"]
            preStop:
              exec:
                command: ["/usr/bin/bash", "-c", "/var/persistent/k8s/web/02_prestop.sh"]
          volumeMounts:
            - name: persistent-storage01
              mountPath: "/var/persistent/"
            - name: host-varlog
              mountPath: "/var/log/host/"
            - name: host-etc
              mountPath: "/etc/host/"
      terminationGracePeriodSeconds: 20
      volumes:
        - name: persistent-storage01
          persistentVolumeClaim:
            claimName: efs-claim
        - name: host-varlog
          hostPath:
            path: "/var/log"
        - name: host-etc
          hostPath:
            path: "/etc"
2

What does kubectl describe say? More specifically the events?

3

Thank you for your response.

Fortunately, I have already solved the problem. It’s because of my rollingUpdate strategy setting.

I changed maxSurge 1 to 2, then my k8s became to run rollingUpdate correctly even when a changed manifest is applied. When I set it as 1, the update behaves like “recreate”.

I doubt it’s a kind of k8s bug, but I don’t think it seriously because it was resolved.

Regrds,