When it comes to your cloud ecosystem and environments, proper planning and management are crucial to minimize production downtime and ensure uninterrupted workload performance. In this blog series “Managing your cloud ecosystems,” we will explore different strategies to help you achieve a smooth and seamless setup with minimal disruption.
Starting off, this blog post will delve into the topic of ensuring continuity of workload during worker node upgrades.
What Are Worker Node Upgrades?
Worker node upgrades involve applying important security updates and patches on a regular basis. To learn more about the different types of worker node upgrades, refer to the IBM Cloud Kubernetes Service documentation on Updating VPC worker nodes and Updating Classic worker nodes.
During an upgrade, some of your worker nodes may become temporarily unavailable. It is crucial to ensure that your cluster has enough capacity to continue running your workload throughout the upgrade process. Implementing a pipeline to update your worker nodes without causing application downtime will allow you to regularly apply worker node upgrades with ease.
Strategies for Classic Worker Nodes
To manage classic worker nodes, create a Kubernetes configmap that specifies the maximum number of worker nodes that can be offline at a time, including during upgrades. You can also use labels to apply different rules to different worker nodes. For detailed instructions, refer to the Kubernetes service documentation on Updating Classic worker nodes in the CLI with a configmap. If you choose not to create a configmap, the default maximum offline worker node limit is 20%.
If you need to keep the total number of worker nodes online, you can temporarily add extra worker nodes to your cluster using the
ibmcloud ks worker-pool resize command during the upgrade. Once the upgrade is complete, you can use the same command to remove the additional worker nodes and return your worker pool to its original size.
Strategies for VPC Worker Nodes
Upgrading VPC worker nodes involves replacing the old nodes with new ones that run on the latest version. While you can upgrade multiple worker nodes simultaneously, they will be unavailable during the process. To ensure sufficient capacity for running your workload, you can either resize your worker pools by temporarily adding extra nodes (similar to the procedure for classic worker nodes) or upgrade your worker nodes one by one.
Whether you choose to implement a configmap, resize your worker pool, or upgrade nodes individually, developing a workload continuity plan before performing worker node upgrades is essential in achieving a smoother and more efficient setup with minimal downtime.
With a plan in place to prevent disruptions during worker node upgrades, stay tuned for the next blog post in our series, where we will discuss the best practices for implementing major, minor, or patch upgrades for your clusters and worker nodes.
Learn more about IBM Cloud Kubernetes Service clusters
What are worker node upgrades?
Worker node upgrades involve applying important security updates and patches on a regular basis to ensure the smooth operation and security of your cloud environment.
How can I ensure workload continuity during worker node upgrades?
To ensure workload continuity during worker node upgrades, you can implement strategies such as creating a Kubernetes configmap, resizing worker pools, or upgrading nodes individually. These strategies help maintain sufficient capacity to run your workload without disruption.
What is the default maximum offline worker node limit for classic worker nodes?
The default maximum offline worker node limit for classic worker nodes is 20%. However, you can customize this by creating a Kubernetes configmap.
In a cloud ecosystem, managing worker node upgrades is essential to minimize downtime and maintain the performance of your workload. This article explores different strategies for ensuring continuity during worker node upgrades, including creating a Kubernetes configmap, resizing worker pools, and upgrading nodes individually. By implementing these strategies, you can upgrade your worker nodes regularly without causing application downtime.