Can We Scale up Too Much or De-scale to Zero Nodes?
Explore how to manage Kubernetes cluster auto-scaling by defining sensible minimum and maximum node thresholds. Understand the risks of scaling too much or down to zero nodes and how to configure these limits on AWS, GCP, and Azure to ensure efficient resource use and cost control.
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Scale or descale without threshold #
If we let Cluster Autoscaler do its “magic” without defining any thresholds, our cluster or our wallet might be at risk.
We might, for example, misconfigure HPA and end up scaling Deployments or StatefulSets to a huge number of replicas. As a result, Cluster Autoscaler might add too many nodes to the cluster. As a result, we could end up paying for hundreds of nodes, even though we need much less. Luckily, AWS, Azure, and GCP limit how many nodes we can have so we cannot scale to infinity. Nevertheless, we should not allow Cluster Autoscaler to go over some limits.
Similarly, there is a danger that Cluster Autoscaler will ...