AWS Direct Connect Traffic Flow with AWS Local Zone

Create AWS Direct Connect gateway (DXGW) "X" and assign a unique autonomous system number (ASN). Attach the Private Virtual Interface (VIF) to DXGW X.

Create DXGW "Y" and assign a unique ASN. Attach the Transit VIF to DXGW Y.

Create a Virtual Private Gateway (VGW) and attach it to DXGW X. Assign a unique ASN to the VGW. Attach the VGW to VPC A.

Create an AWS Transit Gateway (TGW) and attach it to DXGW Y using a DXGW attachment. Attach the TGW to VPC A using a VPC A attachment.

Create a parent subnet (10.0.0.0/24) with an Amazon Elastic Compute Cloud instance in an Availability Zone (AZ1) and associate it with a route table.

Create another subnet (10.0.1.0/24) in the AWS Local Zone where the latency-sensitive application runs. Associate this subnet with a separate Local Zone route table.

Add the AZ1 parent subnet (10.0.0.0/24) in the DXGW Y allowed prefixes list. For more information about allowed prefixes, see Allowed prefixes interactions.

AWS Transit Gateway and DXGW Y advertise the AZ1 parent subnet (10.0.0.0/24) back to on-premises. Traffic destined to the parent subnet follows the TGW path.

Traffic destined to the Local Zone subnet (10.0.1.0/24) follows the shorter VGW path without hairpinning through the Local Zone parent Region.

Avoid routing resources to the Local Zone subnet from on-premises through Transit Gateway because traffic using this path hairpins through the parent Region.