Azure Kubernetes Service (AKS) now allows users to select if they would like their nodes to be deleted or deallocated when scaled down. When a node is deallocated, the attached storage as well as the container image is still present on the node. When scaling up your deployments, all deallocated nodes will be started first before provisioning new nodes. This allows for faster operation speeds as your deployment leverages cached images. Scale-down mode allows you to no longer have to pre-provision nodes and pre-pull container images.
This feature is currently in public preview.
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