Manual Kubernetes Version UpgradeΒΆ

You can upgrade the Kubernetes version on a running system from one supported version to another.

About this task

To complete this task, you will apply the following three updates (patches) and upgrade various systems.

Platform update

The platform update contains metadata for the new Kubernetes version and the Kubernetes networking pods templates for the new Kubernetes version.

Kubeadm update

The kubeadm update upgrades the kubeadm RPM to the new Kubernetes version.

Kubelet and Kubectl update

This Kubernetes update upgrades kubelet and kubectl RPMs to the new Kubernetes version.

Prerequisites

  • The system must be clear of alarms.

  • All hosts must be unlocked, enabled and available.

  • All Kubernetes pods must be ready.

  • The installed applications must be compatible with the new Kubernetes version.

  • All updates required for the new Kubernetes version must be transferred to the active controller.

  • If you are using NetApp Trident in StarlingX 6.0 and have upgraded from the StarlingX previous version, ensure that your NetApp backend version is compatible with Trident 21.04 and follow the steps in Upgrade the NetApp Trident Software to upgrade the Trident drivers to 21.04 before upgrading Kubernetes to version 1.19.

Note

The default version on a fresh install will be Kubernetes 1.21.8, while on an upgrade from StarlingX 6.0 it will be 1.18.1. You will need to upgrade Kubernetes to each version up to 1.21.8 in order to be ready to upgrade to the next version of StarlingX.

Procedure

  1. Upload, apply and install the platform update.

    Use the standard sw-patch, upload, apply and install commands to perform these operations.

  2. List the available Kubernetes versions.

    On a fresh install of StarlingX 6.0, the following output appears:

    ~(keystone_admin)]$ system kube-version-list
+---------+--------+-------------+
| Version | Target | State       |
+---------+--------+-------------+
| v1.18.1 | False  | unavailable |
| v1.19.13| False  | unavailable |
| v1.20.9 | False  | unavailable |
| v1.21.8 | True   | active      |
+---------+--------+-------------+

    If StarlingX was upgraded to 6.0, the following appears:

    ~(keystone_admin)]$ system kube-version-list
+---------+--------+-------------+
| Version | Target | State       |
+---------+--------+-------------+
| v1.18.1 | True   | active      |
| v1.19.13| False  | available   |
| v1.20.9 | False  | unavailable |
| v1.21.8 | False  | unavailable |
+---------+--------+-------------+

    The following meanings apply to the output shown:

    Target

    A value of True means that the target is currently selected for installation.

    State

    Can be one of:

    active

    The version is running everywhere.

    partial

    The version is running somewhere.

    available

    The version can be upgraded to.

    unavailable

    The version is not available for upgrading. Either it is a downgrade or it requires an intermediate upgrade first. Kubernetes can be only upgraded one version at a time.

  3. Confirm that the system is healthy.

    Check the current system health status, resolve any alarms and other issues reported by the system health-query-kube-upgrade command then recheck the system health status to confirm that all System Health fields are set to OK.

    ~(keystone_admin)]$ system health-query-kube-upgrade
    System Health:
    All hosts are provisioned: [OK]
    All hosts are unlocked/enabled: [OK]
    All hosts have current configurations: [OK]
    All hosts are patch current: [OK]
    Ceph Storage Healthy: [OK]
    No alarms: [OK]
    All kubernetes nodes are ready: [OK]
    All kubernetes control plane pods are ready: [OK]
    Required patches are applied: [OK]
    License valid for upgrade: [OK]
    No instances running on controller-1: [OK]
    All kubernetes applications are in a valid state: [OK]
    Active controller is controller-0: [OK]

  4. Start the Kubernetes upgrade.

    For example:

    ~(keystone_admin)]$ system kube-upgrade-start v1.19.13
+-------------------+-------------------+
| Property          | Value             |
+-------------------+-------------------+
| from_version      | v1.18.1           |
| to_version        | v1.19.13          |
| state             | upgrade-started   |
+-------------------+-------------------+

    The upgrade process checks the applied/available updates, the upgrade path, the health of the system, the installed applications compatibility and validates the system is ready for an upgrade.

    Warning

    The command system kube-upgrade-start --force causes the upgrade process to ignore non-management-affecting alarms. Kubernetes cannot be upgraded if there are management-affecting alarms.

  5. Download the Kubernetes images.

    For example:

    ~(keystone_admin)]$ system kube-upgrade-download-images
+--------------+--------------------------------------+
| Property     | Value                                |
+--------------+--------------------------------------+
| uuid         | b5f7dada-2537-4416-9d2c-f9ca9fcd0e22 |
| from_version | v1.18.1                              |
| to_version   | v1.19.13                             |
| state        | downloading-images                   |
| created_at   | 2020-02-20T16:08:48.854869+00:00     |
| updated_at   | None                                 |
+--------------+--------------------------------------+

  6. Confirm that the download has completed.

    ~(keystone_admin)]$ system kube-upgrade-show
+--------------+--------------------------------------+
| Property     | Value                                |
+--------------+--------------------------------------+
| uuid         | b5f7dada-2537-4416-9d2c-f9ca9fcd0e22 |
| from_version | v1.18.1                              |
| to_version   | v1.19.13                             |
| state        | downloaded-images                    |
| created_at   | 2020-02-20T16:08:48.854869+00:00     |
| updated_at   | 2020-02-20T16:10:37.858661+00:00     |
+--------------+--------------------------------------+

  7. Upgrade Kubernetes networking.

    This step must be completed after the first control plane has been upgraded and before upgrading the second control plane.

    ~(keystone_admin)]$ system kube-upgrade-networking
+--------------+--------------------------------------+
| Property     | Value                                |
+--------------+--------------------------------------+
| uuid         | b5f7dada-2537-4416-9d2c-f9ca9fcd0e22 |
| from_version | v1.18.1                              |
| to_version   | v1.19.13                             |
| state        | upgrading-networking                 |
| created_at   | 2020-02-20T16:08:48.854869+00:00     |
| updated_at   | 2020-02-20T16:18:11.459736+00:00     |
+--------------+--------------------------------------+

    The state upgraded-networking will be entered when the networking upgrade has completed.

  8. Upgrade the control plane on the first controller.

    ~(keystone_admin)]$ system kube-host-upgrade controller-1 control-plane
+-----------------------+-------------------------+
| Property              | Value                   |
+-----------------------+-------------------------+
| control_plane_version | v1.18.1                 |
| hostname              | controller-1            |
| id                    | 2                       |
| kubelet_version       | v1.18.1                 |
| personality           | controller              |
| status                | upgrading-control-plane |
| target_version        | v1.19.13                |
+-----------------------+-------------------------+

    You can upgrade either controller first.

    The state upgraded-first-master will be entered when the first control plane upgrade has completed.

  9. Upgrade the control plane on the second controller.

    ~(keystone_admin)]$ system kube-host-upgrade controller-0 control-plane
+-----------------------+-------------------------+
| Property              | Value                   |
+-----------------------+-------------------------+
| control_plane_version | v1.18.1                 |
| hostname              | controller-0            |
| id                    | 1                       |
| kubelet_version       | v1.18.1                 |
| personality           | controller              |
| status                | upgrading-control-plane |
| target_version        | v1.19.13                |
+-----------------------+-------------------------+

    The state upgraded-second-master will be entered when the upgrade has completed.

  10. Show the Kubernetes upgrade status for all hosts.

    ~(keystone_admin)]$ system kube-host-upgrade-list
+----+--------------+-------------+----------------+-----------------------+-----------------+--------+
| id | hostname     | personality | target_version | control_plane_version | kubelet_version | status |
+----+--------------+-------------+----------------+-----------------------+-----------------+--------+
| 1  | controller-0 | controller  | v1.19.13       | v1.19.13              | v1.18.1         | None   |
| 2  | controller-1 | controller  | v1.19.13       | v1.19.13              | v1.18.1         | None   |
| 3  | worker-0     | worker      | v1.18.1        | N/A                   | v1.18.1         | None   |
| 4  | worker- 1    | worker      | v1.18.1        | N/A                   | v1.18.1         | None   |
+----+--------------+-------------+----------------+-----------------------+-----------------+--------+

    The control planes of both controllers are now upgraded to v1.19.13.

  11. Upgrade kubelet on both controllers.

    Either controller can be upgraded first.

    The kubelets on all controller hosts must be upgraded before upgrading kubelets on worker hosts.

    For each controller, do the following.

    1. For non AIO-SX systems, lock the controller.

      For example:

      ~(keystone_admin)]$ system host-lock controller-1

      Note

      For All-In-One Simplex systems, the controller must not be locked.

    2. Apply the upgrade.

      For example:

      ~(keystone_admin)]$ system kube-host-upgrade controller-1 kubelet
+-----------------------+-------------------+
| Property              | Value             |
+-----------------------+-------------------+
| control_plane_version | v1.19.13          |
| hostname              | controller-1      |
| id                    | 2                 |
| kubelet_version       | v1.18.1           |
| personality           | controller        |
| status                | upgrading-kubelet |
| target_version        | v1.19.13          |
+-----------------------+-------------------+

    3. For non AIO-SX systems, unlock the controller.

      For example:

      ~(keystone_admin)]$ system host-unlock controller-1

  12. Show the Kubernetes upgrade status.

    ~(keystone_admin)]$ system kube-upgrade-show
+--------------+--------------------------------------+
| Property     | Value                                |
+--------------+--------------------------------------+
| uuid         | b5f7dada-2537-4416-9d2c-f9ca9fcd0e22 |
| from_version | v1.18.1                              |
| to_version   | v1.19.13                             |
| state        | upgrading-kubelets                   |
| created_at   | 2020-02-20T16:08:48.854869+00:00     |
| updated_at   | 2020-02-20T21:53:16.347406+00:00     |
+--------------+--------------------------------------+

  13. Upgrade kubelet on all worker hosts.

    Multiple worker hosts can be upgraded simultaneously provided there is sufficient capacity remaining on other worker hosts.

    For each worker host, do the following:

    1. Lock the host.

      For example:

      ~(keystone_admin)]$ system host-lock worker-1

    2. Perform the upgrade.

      For example:

      ~(keystone_admin)]$ system kube-host-upgrade worker-1 kubelet
+-----------------------+-------------------+
| Property              | Value             |
+-----------------------+-------------------+
| control_plane_version | v1.19.13          |
| hostname              | worker-1          |
| id                    | 3                 |
| kubelet_version       | v1.18.1           |
| personality           | worker            |
| status                | upgrading-kubelet |
| target_version        | v1.19.13          |
+-----------------------+-------------------+

    3. Unlock the host.

      For example:

      ~(keystone_admin)]$ system host-unlock worker-1

  14. Complete the Kubernetes upgrade.

    ~(keystone_admin)]$ system kube-upgrade-complete
+--------------+--------------------------------------+
| Property     | Value                                |
+--------------+--------------------------------------+
| uuid         | 4e942297-465e-47d4-9e1b-9fb1630be33c |
| from_version | v1.18.1                              |
| to_version   | v1.19.13                             |
| state        | upgrade-complete                     |
| created_at   | 2020-02-19T20:59:51.079966+00:00     |
| updated_at   | 2020-02-24T15:03:34.572199+00:00     |
+--------------+--------------------------------------+

  15. Remove the alarm 900.007 (Kubernetes upgrade in progress) if it is still running after the upgrade.

    ~(keystone_admin)]$ system kube-upgrade-delete