This chart bootstraps a cluster-autoscaler deployment on a Kubernetes cluster using the Helm package manager. Cluster Autoscaler is a tool that automatically adjusts the size of the Kubernetes cluster when one of the following conditions is true:
Cluster Autoscaler increases the size of the cluster when:
We recommend using Cluster Autoscaler with the Kubernetes master version for which it was meant. The below combinations have been tested on GCP. We don’t do cross version testing or compatibility testing in other environments. Some user reports indicate successful use of a newer version of Cluster Autoscaler with older clusters, however, there is always a chance that it won’t work as expected. Cluster Autoscaler 0.5.X is the official version shipped with k8s 1.6. We’ve done some basic tests using k8s 1.6 / CA 0.6 and we’re not aware of any problems with this setup. However, Cluster Autoscaler internally simulates Kubernetes’ scheduler and using different versions of scheduler code can lead to subtle issues.
Cluster Autoscaler is designed to run on Kubernetes master node. This is the default deployment strategy on GCP. It is possible to run a customized deployment of Cluster Autoscaler on worker nodes, but extra care needs to be taken to ensure that Cluster Autoscaler remains up and running. Users can put it into kube-system namespace (Cluster Autoscaler doesn’t scale down node with non-mirrored kube-system pods running on them) and add a scheduler.alpha.kubernetes.io/critical-pod annotation (so that the rescheduler, if enabled, will kill other pods to make space for it to run).
Tell us about a new Kubernetes application
Never miss a thing! Sign up for our newsletter to stay updated.
Discover and learn about everything Kubernetes