AWS Gateway Load Balancer now supports TCP Reset for faster failure recovery

AWS Gateway Load Balancer (GWLB) supports sending TCP Reset (RST) packets when targets fail, are deregistered, or TCP flows time out. This allows TCP endpoints to quickly detect bad connections and establish new flows, reducing traffic disruption from minutes to seconds. Previously, existing TCP connections would continue to the failed target, causing delays of several minutes due to retries and backoff mechanisms. Enabling this feature causes GWLB to send TCP Resets to incoming traffic, indicating the connection is no longer valid. TCP Reset is disabled by default for compatibility, but can be enabled per target group using the AWS Management Console, AWS CLI, or API. The three triggers-target failure, deregistration (after connection drain), and TCP idle timeout expiration-are supported independently. This feature is available for both new and existing Gateway Load Balancers in all AWS regions where GWLB is offered, at no additional cost.

Why it matters

This update is relevant for users who need to accelerate failure recovery for network traffic and developers of applications using AWS Gateway Load Balancer. GWLB is AWS's gateway load balancer that provides fast traffic forwarding and security, and this feature improves recovery during failures.