What Are Kubernetes Versions?
Kubernetes versions are identified by three numerical components: major, minor, and patch. This system follows semantic versioning (semver) rules, allowing users to understand the level of changes in each release. The versioning system helps in managing the evolution of Kubernetes, addressing bugs, adding features, and improving user experience.
As mentioned above, there are three types of version releases in Kubernetes:
- Major versions: Major versions in Kubernetes signify fundamental changes that may not be backward compatible. These versions introduce significant advancements or changes in architecture, requiring careful planning and testing before upgrading.
- Minor versions: Minor versions of Kubernetes add new features and improvements in a backward-compatible manner. These releases bring enhancements that extend the capabilities of Kubernetes without requiring major adjustments to existing deployments.
- Patch versions: Patch versions in Kubernetes address bugs and security vulnerabilities, providing fixes without adding new features. These releases are critical for maintaining the security and stability of Kubernetes deployments. Patch versions ensure minimal impact on operations, focusing on improvements and fixes that do not introduce significant changes.
The Importance of Keeping Kubernetes Up-to-Date
Having the latest version of Kuberenetes is essential for several reasons:
Enhanced Security
New versions fix vulnerabilities discovered in earlier releases. Neglecting updates can expose clusters to attacks, compromising the integrity and confidentiality of applications. Security enhancements are often included in new releases, providing better default settings and new features to improve cluster security.
Access to Latest Features
Each Kubernetes release introduces new features and improvements. Updating enables access to these features, allowing users to leverage the latest advancements for better performance, usability, and reliability. In addition, new features often address user feedback, allowing the Kubernetes project to respond to new use cases and requirements.
Improved Stability and Performance
Updates often include optimizations that improve the performance and stability of Kubernetes. These enhancements contribute to smoother operations and reduced downtime. By upgrading, users can take advantage of these improvements, ensuring their deployments run more efficiently and are less prone to failure.
Where Can You Get the Latest Version of Kubernetes?
Latest Version of Vanilla Kubernetes
You can find the latest version of Kubernetes in the official releases page. This page provides links to the schedule and changelog of the latest Kubernetes minor versions.
Visit the Kubernetes releases page
Latest Version of Google Kubernetes Engine (GKE)
The GKE releases page lists Kubernetes minor versions and the corresponding GKE patch version and container-optimized OS (COS) version. For each version, the page provides release notes.
Visit the Google Kubernetes Engine release notes
Latest Version of AWS Elastic Kubernetes Service (EKS)
The Amazon EKS platform versions page lists recent Kubernetes versions, and shows the respective Amazon EKS version or versions corresponding to each release. It links to release notes for each version.
Visit the Amazon EKS platform versions page
Latest Version of Azure Kubernetes Service (AKS)
The AKS supported Kubernetes versions page provides a release calendar that shows the dates of preview release, GA release, and end of life for recent Kubernetes versions in the AKS service. It also provides details of AKS components with breaking changes in each version.
Visit the AKS supported Kubernetes versions page
How to Check Your Kubernetes Version with kubectl
To check your Kubernetes version, run the following command:
kubectl version
This command displays the client and server versions, showing the version of kubectl and the Kubernetes cluster it’s communicating with. It’s useful for troubleshooting and ensuring compatibility between kubectl and the Kubernetes cluster.
Understanding the Kubernetes Release Cycle
A Kubernetes release follows a structured process of approximately four months, as shown in the following diagram:
Source: Kubernetes
Each release follows three phases:
- Enhancement Definition: During this stage, the community and contributors discuss and define the enhancements that could be included in the upcoming release. This process is ongoing throughout the year and is not limited to any specific time frame.
- Implementation phase: Where the approved enhancements are developed. Contributors work on coding the new features, making improvements, and fixing bugs. The project emphasizes continuous integration testing to ensure that the codebase remains stable and that any changes do not adversely affect existing functionalities.
- Stabilization phase: This occurs towards the end of the cycle, marked by a Code Freeze. During this period, which lasts for about two weeks, the focus shifts to fixing critical bugs and security vulnerabilities.
After the Stabilization phase, the release enters a brief period where final adjustments and documentation updates are made. Following this, the new version is officially released, and the master branch re-opens for development towards the next milestone.
Best Practices for Upgrading Kubernetes Versions
There are several measures that can help ensure Kubernetes is always updated to the latest version while minimizing the impact to your system.
Review the Release Notes
Before upgrading, review the release notes for the target Kubernetes version. These notes detail new features, improvements, deprecations, and bug fixes. Understanding these changes helps in assessing the impact of the upgrade on your deployments.
Release notes also provide critical information on breaking changes and migration steps, if necessary. This preparation ensures a smooth upgrade process, minimizing disruptions and leveraging new Kubernetes functionalities effectively.
Test in a Staging Environment
Upgrading Kubernetes in a staging environment before rolling the update to production is crucial. This testing phase identifies potential issues and incompatibilities with applications or configurations. It allows for adjustments and planning to ensure a seamless transition during the actual upgrade.
Emulating the production environment as closely as possible during testing provides confidence in the upgrade process. It ensures that the new Kubernetes version operates as expected under realistic conditions.
Gradual Rollouts
Implementing gradual rollouts decreases risk during upgrades. Start with less critical environments, progressively moving to more critical ones. This phased approach allows for monitoring effects and addressing any issues before wider deployment.
Use Automated Tools
Automated Kubernetes management tools streamline the upgrade process, reducing manual efforts and errors. Tools like Kubernetes Operations (kops), Kubeadm, and cloud provider managed services can automate many steps of the upgrade, or even automate the entire cluster upgrade process.
Follow the Supported Upgrade Path
Skipping versions or ignoring prerequisites can introduce issues. Following the recommended path outlined in Kubernetes documentation or by cloud providers ensures compatibility and stability. Familiarizing yourself with upgrade paths and dependencies prevents potential problems, ensuring a successful upgrade.
Update Deployments and Configurations
Upgrading may require adjustments to deployments and configurations to leverage new features or maintain compatibility. Reviewing and updating resource definitions, manifests, and other settings is essential. Making necessary adjustments ensures that applications benefit from the latest Kubernetes improvements and functionalities.
Troubleshooting Kubernetes Upgrades with Komodor
Without the right tools and expertise in place, the troubleshooting process can become stressful, ineffective and time-consuming. Some best practices can help minimize the chances of things breaking down, but eventually something will go wrong – simply because it can.
This is where Komodor comes in – Komodor is the Continuous Kubernetes Reliability Platform, designed to democratize K8s expertise across the organization and enable engineering teams to leverage its full value.
Komodor’s platform empowers developers to confidently monitor and troubleshoot their workloads while allowing cluster operators to enforce standardization and optimize performance.
Specifically when it comes to Kubernetes version upgrades, Komodor enables you to proactively monitor each cluster’s End-of-Life status, as well as its associated APIs. With Komodor, your infrastructure remains up-to-date and compliant, while preventing potential issues from occurring.
By leveraging Komodor, companies of all sizes significantly improve reliability, productivity, and velocity. Or, to put it simply – Komodor helps you spend less time and resources on managing Kubernetes, and more time on innovating at scale.
If you are interested in checking out Komodor, use this link to sign up for a Free Trial.
