aws AWS What's New ·

ECS Service Connect adds zone-aware routing

infraawsengineer
feature patch

Amazon ECS Service Connect now supports zone-aware routing, which prioritizes service-to-service traffic within the same Availability Zone to cut data transfer costs and latency. This feature automatically balances load across services and redistributes traffic across healthy zones if local endpoints fail. It is enabled by default for new and existing services and available in all supported AWS regions at no additional cost.

  • ECS Service Connect introduces zone-aware routing
  • Eliminates trade-off between cost and resilience for cross-AZ traffic
  • Automatic fallback and monitoring capabilities
  • Default enablement and availability
Features (1)
  • ECS Service Connect introduces zone-aware routing

    ECS Service Connect now preferentially routes service-to-service traffic to endpoints in the same Availability Zone as the originating task. This reduces cross-AZ data transfer costs and latency while maintaining balanced load and availability.

Enhancements (1)
  • Eliminates trade-off between cost and resilience for cross-AZ traffic

    Zone-aware routing addresses the previous need to choose between high cross-zone data transfer costs and resilience by distributing applications across multiple Availability Zones.

Notes (2)
  • Automatic fallback and monitoring capabilities

    When local endpoints become unhealthy or capacity is insufficient, traffic automatically redirects to healthy AZs without overloading zones. VPC Flow Logs with AZ metadata can be used to monitor cross-AZ traffic.

  • Default enablement and availability

    Zone-aware routing is enabled by default for all new and existing ECS services, requiring no additional infrastructure or code changes. Existing services need a one-time redeployment to activate this behavior. It is available in all AWS commercial and AWS GovCloud (US) Regions where ECS Service Connect is supported, at no extra cost.

Read the original announcement →

https://aws.amazon.com/about-aws/whats-new/2026/07/ecs-service-connect-zone-aware/