Automatic Version Upgrade

1. Overview of Kubernetes Version Management Process in FPTCloud

- FPTCloud releases and updates Kubernetes versions in accordance with the standards of the Kubernetes open-source software (OSS) community.

- The Kubernetes version format is x.y.z, where x is the major version. Major versions increment from (x.y) to (x+1.y). y is the minor version. Deprecated APIs are removed in new minor versions, which increment from 1.y to (1.y+1). For example, version 1.25 is a minor release of 1.25. z is the patch release. Patches and updates to fix bugs or security holes in the minor version are released through patch releases.

- FPTCloud supports managing up to four of the most stable Kubernetes minor versions simultaneously. The highest version among these four is selected as the default version. These stable versions are rigorously tested and ready for production deployment. Older versions are labeled as deprecated until their end-of-life date, as specified by FPTCloud in release notes.

- Additionally, FPTCloud supports new Kubernetes versions backed by the Kubernetes OSS community. These new versions carry a "Beta" tag and undergo refinement toward completion based on internal testing and user experience feedback. Once ready for production use, these versions lose their "Beta" tag and become "Stable" or "GA (Generally Available)" versions.

- Older versions (those no longer receiving standard support from the Kubernetes community and FPT Cloud) are not covered by technical support. New features related to Kubernetes fixes and new features from cloud providers will not be updated in unsupported versions. Security vulnerabilities and risks will also not be updated or fixed in these versions. Note: Older versions are not covered by FPT Cloud support or SLA guarantees.

- The Kubernetes version for standard clusters differs from the Kubernetes version for clusters using GPUs (typically, the default version for GPU clusters is one minor version lower than standard clusters).

- The worker OS image version is continuously patched to address security vulnerabilities. Currently, FPTCloud uses the Ubuntu 22.04 OS image for worker nodes in Kubernetes clusters.

- Two months before the end of standard support, each version enters maintenance status and is displayed in the portal interface. For clusters running on versions approaching end-of-life, the VPC owner user is notified via email once daily one month prior. This allows the user to either manually upgrade the version or configure the auto-upgrade feature so the cluster upgrades automatically at the end of standard support. If the user manually upgrades the version during this period, the Kubernetes service will cease sending emails to the VPC owner user.

- For clusters with automatic version upgrades configured, an email notifying the VPC owner user of the specific upgrade time will be sent three days prior to the automatic upgrade.

2. Detailed usage instructions for the automatic version upgrade feature:

- Managed Kubernetes clusters using a version that is one or more minor versions older than the latest version supported by FPT Cloud cannot use the automatic version upgrade feature. Users must manually upgrade the version for these clusters.

- For example, if a cluster is using version 1.24.14 and FPT Cloud supports Kubernetes versions 1.26 to 1.29, this feature cannot be used for that cluster. To use this feature, the cluster must be manually upgraded to version 1.25.

- The version upgrade mechanism follows a rolling update mechanism. Workers running the new minor version are created simultaneously across all worker groups. After these workers reach the Ready state and are prepared to run workloads, Kubernetes drains the workers running the old minor version. Once draining is complete, the old workers are deleted. This process repeats sequentially until all workers within a group have been replaced.

2.1. Initialization of Managed Kubernetes Clusters:

- When initializing a Managed Kubernetes cluster, the Auto Upgrade Version feature is disabled by default, as shown below.

- Click the "?" icon to view detailed information about the key milestones for Kubernetes versions supported by FPT Cloud.

- If you enable the Auto Upgrade Version feature without setting an upgrade time, the default upgrade time will be 07:00 GMT+7 on the first day of the end of standard support for that version.

- After setting the auto-upgrade execution time, you can view the end-of-support date for the current version, the earliest possible date for the auto-upgrade to occur, and a summary of the auto-upgrade schedule.

- Once the automatic upgrade version schedule is set during the cluster initialization process, click "Next" to proceed to the "Nodes Pool" configuration step.

2.2. Changing the Automatic Upgrade Version Settings for an Existing Cluster

Note:

- Even if an auto-upgrade version is configured for an existing Managed Kubernetes cluster, users can still manually upgrade the version as usual, just like clusters where this feature is disabled.

- To cancel the auto-upgrade schedule for a Managed Kubernetes cluster with auto-upgrade enabled, you must either disable the auto-upgrade feature or modify the auto-upgrade schedule before 01:00 GMT+7 on the day FPT Cloud automatically upgrades the version. Example: Cluster A has automatic version upgrades enabled and is scheduled for an automatic upgrade on June 25, 2024, at 04:00 GMT+7. To cancel the automatic upgrade schedule, you must either disable the automatic upgrade feature or change the automatic upgrade schedule by 01:00 GMT+7 on June 25, 2024. Any changes made after this time will be invalid, and the automatic version upgrade will proceed as scheduled at 04:00 GMT+7 on June 25, 2024.

• Enable the automatic upgrade feature: