Release 2021-07-22
This release is rolling out to all regions - estimated time for completed roll out is 2021-07-29 for public cloud and 2021-08-03 for sovereign clouds.
Announcements
- Azure Kubernetes Service (AKS) will stop publishing Ubuntu 16.04 image change moving forward.
- As a response to customer feedback and issues with previous Kubernetes version patches that left a lot of users with hard options. The AKS Team is extending a limited scope of support for all clusters and nodepools on 1.18 as a courtesy. Customers with clusters and nodepools on 1.18 after the announced deprecation date of 2021-06-30 will be granted an extension of capabilities outside the usual scope of support for deprecated versions .The scope of this limited extension is effective from '2021-06-30 to 2021-07-31' and is limited to the following:
- Creation of new clusters and nodepools on 1.18.
- CRUD operations on 1.18 clusters.
- Azure Support of non-Kubernetes related, platform issues. Platform issues include trouble with networking, storage, or compute running on Azure. Any support requests for K8s patching and troubleshooting will be requested to upgrade into a supported version.
- Previous pod security policy (preview) deprecation was June 30th 2021. To better align with Kubernetes Upstream pod security policy (preview) deprecation will begin with Kubernetes version 1.21, with its removal in version 1.25. As Kubernetes Upstream approaches that milestone, the Kubernetes community will be working to document viable alternatives.
Release Notes
- Features
- New Kubernetes patch version available, v.1.21.2.
- Preview Features
- Upgrade your Windows nodepool from Docker to Containerd by the following two methods. Note that the Kubernetes version should be > 1.20.0 and the feature flag UseCustomizedWindowsContainerRuntime should be registered under your current Azure subscription. Reminder that Docker is removed in Kubernetes 1.24 completely, use the following commands to move your workload from Docker to Containerd now.
- To upgrade a specific nodepool to use containerd:
az aks nodepool upgrade --cluster-name $CLUSTERNAME --name $NODEPOOLNAME --resource-group $RGNAME --kubernetes-version 1.21.1 --aks-custom-headers WindowsContainerRuntime=containerd - To upgrade the cluster to use containerd for all Windows nodepools:
az aks upgrade --cluster-name $CLUSTERNAME --resource-group $RGNAME --kubernetes-version 1.21.1 --aks-custom-headers WindowsContainerRuntime=containerd
- To upgrade a specific nodepool to use containerd:
- Upgrade your Windows nodepool from Docker to Containerd by the following two methods. Note that the Kubernetes version should be > 1.20.0 and the feature flag UseCustomizedWindowsContainerRuntime should be registered under your current Azure subscription. Reminder that Docker is removed in Kubernetes 1.24 completely, use the following commands to move your workload from Docker to Containerd now.
- Behavioral Changes
- Cluster autoscaler will now enforce the minimum count in cases where the actual count drops below that. For example, Spot eviction or changing the minimum count value from the AKS API. In the past, the autoscaler operated and respected the minimum count but never interfered to enforce it if external factors affect it.
- Component Updates
- AKS Ubuntu 18.04 image updated to AKSUbuntu-1804-2021.07.17.
- AKS Windows image has been updated to 2019-datacenter-core-smalldisk-17763.2061.210714.