kubespray/roles/kubernetes/control-plane/tasks/kubeadm-upgrade.yml

---
- name: Ensure kube-apiserver is up before upgrade
  import_tasks: check-api.yml

- name: Kubeadm | Preflight admission readiness check
  command:
    cmd: "{{ kubectl }} create --dry-run=server -f -"
    stdin: >-
      {"apiVersion":"batch/v1","kind":"Job","metadata":{"generateName":"upgrade-preflight-probe-","namespace":"kube-system"},"spec":{"template":{"spec":{"containers":[{"name":"pause","image":"{{ pod_infra_image_repo }}:{{ pod_infra_image_tag }}"}],"restartPolicy":"Never"}}}}
  register: preflight_check_result
  retries: "{{ kubeadm_upgrade_preflight_check_retries }}"
  delay: "{{ kubeadm_upgrade_preflight_check_delay }}"
  until: preflight_check_result.rc == 0
  changed_when: false
  failed_when: false
  when:
  - kubeadm_upgrade_preflight_check_enabled
  - inventory_hostname == first_kube_control_plane
  environment:
    PATH: "{{ bin_dir }}:{{ ansible_env.PATH }}"

- name: Kubeadm | Warn if preflight admission check failed
  debug:
    msg: >-
      WARNING: Preflight admission dry-run failed after {{ kubeadm_upgrade_preflight_check_retries }} retries.
      The admission pipeline may not be ready. kubeadm upgrade apply may fail with [ERROR CreateJob].
      See Kubernetes issue https://github.com/kubernetes/kubernetes/issues/124237 for details.
  when:
  - kubeadm_upgrade_preflight_check_enabled
  - inventory_hostname == first_kube_control_plane
  - preflight_check_result.rc is defined and preflight_check_result.rc != 0

# kubeadm upgrade reads ClusterConfiguration only from the kubeadm-config ConfigMap.
# Upload it first. Then kubeadm upgrades etcd on one node at a time.
- name: Kubeadm | Upload ClusterConfiguration before upgrade
  command: "{{ bin_dir }}/kubeadm init phase upload-config kubeadm --config {{ kube_config_dir }}/kubeadm-config.yaml"
  register: kubeadm_upload_cluster_config
  retries: 3
  until: kubeadm_upload_cluster_config.rc == 0
  when:
  - inventory_hostname == first_kube_control_plane

- name: Kubeadm | Upgrade first control plane node to {{ kube_version }}
  command: >-
    timeout -k 600s 600s
    {{ bin_dir }}/kubeadm upgrade apply -y v{{ kube_version }}
    --config={{ kube_config_dir }}/kubeadm-config.yaml
  register: kubeadm_upgrade
  when: inventory_hostname == first_kube_control_plane
  failed_when: kubeadm_upgrade.rc != 0 and "field is immutable" not in kubeadm_upgrade.stderr
  environment:
    PATH: "{{ bin_dir }}:{{ ansible_env.PATH }}"

- name: Kubeadm | Upgrade other control plane nodes to {{ kube_version }}
  command: >-
    {{ bin_dir }}/kubeadm upgrade node
    --config={{ kube_config_dir }}/kubeadm-config.yaml
  register: kubeadm_upgrade
  when: inventory_hostname != first_kube_control_plane
  failed_when: kubeadm_upgrade.rc != 0 and "field is immutable" not in kubeadm_upgrade.stderr
  environment:
    PATH: "{{ bin_dir }}:{{ ansible_env.PATH }}"

# kubeadm upgrade no longer reconciles ClusterConfiguration and KubeProxyConfiguration changes, this must be done separately after upgrade to ensure the latest config is applied
- name: Update kubeadm and kubelet configmaps after upgrade
  command: "{{ bin_dir }}/kubeadm init phase upload-config all --config {{ kube_config_dir }}/kubeadm-config.yaml"
  register: kubeadm_upload_config
  # Retry is because upload config sometimes fails
  retries: 3
  until: kubeadm_upload_config.rc == 0
  when:
  - inventory_hostname == first_kube_control_plane

- name: Update kube-proxy configmap after upgrade
  command: "{{ bin_dir }}/kubeadm init phase addon kube-proxy --config {{ kube_config_dir }}/kubeadm-config.yaml"
  register: kube_proxy_upload_config
  # Retry is because upload config sometimes fails
  retries: 3
  until: kube_proxy_upload_config.rc == 0
  when:
  - inventory_hostname == first_kube_control_plane
  - ('addon/kube-proxy' not in kubeadm_init_phases_skip)

- name: Rewrite kubeadm managed etcd static pod manifests with updated configmap
  command: "{{ bin_dir }}/kubeadm init phase etcd local --config {{ kube_config_dir }}/kubeadm-config.yaml"
  when:
  - etcd_deployment_type == "kubeadm"
  notify: Control plane | restart kubelet

- name: Rewrite kubernetes control plane static pod manifests with updated configmap
  command: "{{ bin_dir }}/kubeadm init phase control-plane all --config {{ kube_config_dir }}/kubeadm-config.yaml"
  notify: Control plane | restart kubelet

- name: Flush kubelet handlers
  meta: flush_handlers

- name: Ensure kube-apiserver is up after upgrade and control plane configuration updates
  import_tasks: check-api.yml

- name: Kubeadm | Remove binding to anonymous user
  command: "{{ kubectl }} -n kube-public delete rolebinding kubeadm:bootstrap-signer-clusterinfo --ignore-not-found"
  when: remove_anonymous_access

- name: Kubeadm | clean kubectl cache to refresh api types
  file:
    path: "{{ item }}"
    state: absent
  with_items:
  - /root/.kube/cache
  - /root/.kube/http-cache

# FIXME: https://github.com/kubernetes/kubeadm/issues/1318
- name: Kubeadm | scale down coredns replicas to 0 if not using coredns dns_mode
  command: >-
    {{ kubectl }}
    -n kube-system
    scale deployment/coredns --replicas 0
  register: scale_down_coredns
  retries: 6
  delay: 5
  until: scale_down_coredns is succeeded
  run_once: true
  when:
  - kubeadm_scale_down_coredns_enabled
  - dns_mode not in ['coredns', 'coredns_dual']
  changed_when: false

- name: Kubeadm | cleanup old upgrade backups
  import_tasks: kubeadm-backup-cleanup.yml