Karpenter now supports Amazon Application Recovery Controller zonal shift

Amazon Elastic Kubernetes Service (Amazon EKS) now supports Amazon Application Recovery Controller (ARC) zonal shift and zonal autoshift when using the open source Karpenter project for compute provisioning. ARC helps you manage and coordinate recovery for your applications across AWS Regions and Availability Zones (AZs). With this launch, you can better maintain Kubernetes application availability by automating the process of shifting in-cluster network traffic away from an impaired AZ.

Customers increasingly deploy highly available applications in Amazon EKS across multiple AZs to eliminate a single point of failure. With ARC zonal shift, you can temporarily mitigate an AZ impairment by redirecting in-cluster network traffic away from the impacted AZ. For a fully automated experience, authorize AWS to manage this on your behalf using ARC zonal autoshift, which includes practice runs to verify your cluster functions as expected with one less AZ. When a zonal shift is activated for your EKS cluster, Karpenter stops provisioning new capacity in the impaired AZ, halts voluntary disruptions such as consolidation and drift for nodes in that AZ, and prevents voluntary disruptions in healthy zones if they depend on scheduling pods to the impaired zone. Pods with strict scheduling requirements such as volume affinities that require the impaired zone will not trigger launch attempts. When the zonal shift expires or is canceled, Karpenter resumes normal operations.

This Karpenter feature works with both manual zonal shifts and zonal autoshifts. No custom ARC resources are required as Karpenter integrates directly with the existing EKS cluster ARC resource. To enable zonal shift support, set the ENABLE_ZONAL_SHIFT setting in your Karpenter settings. To learn more, visit the Karpenter documentation and the ARC zonal shift documentation.