Cluster upgrades
Introduction
Kubernetes versions are released approximately three times a year, introducing enhancements, security updates, and bug fixes. The planning and initiation of a cluster upgrade is a manual task that requires coordination with our customers.
To schedule the upgrade of your cluster(s), we require a designated point of contact for coordination.
For customers with multiple clusters, please provide your preferred sequence and timeline for upgrades. If you haven’t shared this information yet, kindly submit a support ticket with these details.
Upgrade Planning
Upgrades are scheduled in consultation with the customer and can be done on at the initiative of either Elastx or the customer. If the customer does not initiate the planning of an upgrade, we will reach out to the designated contact in a support ticket at least twice a year with suggested upgrade dates.
NOTE: Upgrades are not performed during our changestop periods:
- In general the full month of July and through the first week of August
- December 23rd to January 2nd
Before scheduling and confirming a time slot, please review the relevant changelog and the Kubernetes Deprecated API Migration guide:
- Elastx PcaaS Changelog: https://docs.elastx.cloud/docs/kubernetes/changelog/
- Kubernetes Deprecated API Migration Guide: https://kubernetes.io/docs/reference/using-api/deprecation-guide/
Upgrade Process
NOTE Please refrain from making any changes while the upgrade is in progress.
The duration of the upgrade typically ranges from 1 to 3 hours, depending on the size of the cluster.
The upgrade starts with the control plane nodes followed by the worker nodes, one nodegroup at a time.
Steps Involved
- A new node with the newer version is added to the cluster to replace the old node.
- Once the new node is ready, the old node is drained.
- Once all transferable loads have been migrated, the old node is removed from the cluster.
- This process is repeated until all nodes in the cluster have been upgraded.
NOTE When using public IPs on worker nodes to ensure predictable egress IP, a previously unused IP will be assigned to the new worker node. This IP should have been provided to you in a list of all allocated IPs during your request for adding public IPs on the worker nodes.
Support and Communication During Upgrades
The engineer responsible for executing the upgrade will notify you through the support ticket when the upgrade begins and once it is completed. The support ticket serves as the primary channel for communication during the upgrade process. If you have any concerns or questions about the upgrade, please use the support ticket to reach out.
Additional Information
- Upon request, upgrades can be scheduled outside office hours if needed. Upgrades outside of office hours depend on personnel availability and comes at an additional fee, see current price for professional services.
- Our Kubernetes service includes up to four version upgrades per year; additional upgrades can be performed at an extra cost.
- To address critical security vulnerabilities, additional upgrades can be performed and will not count against the four upgrades included per year.
- In a previous Tech-fika, we discussed how to build redundancy and implement autoscaling with our Kubernetes service. You can access the presentation here to help you prepare for a smoother upgrade experience.