Azure Application Gateway is an application delivery controller-as-a-service offering that provides layer 7 load balancing, security, and web application firewall functionality.
Autoscaling functionality is available in preview as part of the new zone redundant SKU in all public Azure regions. With this support, you no longer need to choose an instance count or size when deploying Application Gateways. Deploy an autoscaling Application Gateway that can scale up or down automatically based on application traffic load requirements.
Autoscaling also takes into account zonal resiliency and spreads its instances across Azure Zones to provide higher resiliency, availability, and scale. In addition, application gateway natively integrates with autoscaling backend like virtual machine scale set, thus providing an end-to-end elastic experience.
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