AKS support for Ubuntu 18.04 as the Node Operating System (OS) is now generally available. Ubuntu 18.04 is a Long Term Support (LTS) release and contains important improvements and fixes at the OS level.
Node pools created on Kubernetes v1.18 or greater will now default to a required AKS Ubuntu 18.04 node image. Node pools on a supported Kubernetes version less than 1.18 will receive AKS Ubuntu 16.04 as the node image, but will be updated to AKS Ubuntu 18.04 once the node pool Kubernetes version is updated to v1.18 or greater.
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