Configure Variables

Step 1 — Configure variables

Copy and edit terraform.tfvars. Replace every # REPLACE value:

aws_region = "ap-southeast-1"
gcp_region = "asia-southeast1"

gcp_project_id     = "your-gcp-project-id"       # REPLACE
gcp_transport_name = "demo-interconnect-transport"

aws_vpc_cidr       = "10.0.0.0/16"   # advertised toward GCP
aws_subnet_cidr    = "10.0.1.0/24"
aws_dx_gateway_asn = 64512           # private ASN for the DX Gateway

gcp_vpc_cidr = "10.1.0.0/16"        # advertised toward AWS

TERRAFORM TERRAFORM
HashiCorp Terraform — infrastructure-as-code tool used to provision the base AWS and GCP resources in this demo. generates an ED25519 SSH key pair for the GCE GCE
Google Compute Engine — GCP virtual machine instances. The demo GCE VM is reachable via IAP tunnel SSH. debian user automatically. You’ll retrieve the private key after apply (see Step 7).

CIDR rules

Caution

• aws_vpc_cidr and gcp_vpc_cidr must not overlap. - aws_subnet_cidr must fit inside aws_vpc_cidr. - These CIDRs CIDRs
  Classless Inter-Domain Routing — a notation for IP address ranges (e.g. 10.0.0.0/16). AWS and GCP VPC CIDRs must not overlap for interconnect routing. are exchanged across the Interconnect — keep them stable before Step 3.

Variable reference

Variable	Description
aws_region	AWS region (Interconnect source)
gcp_region	Paired GCP region (Interconnect destination)
gcp_project_id	GCP project ID
gcp_transport_name	Name for the gcloud transport resource
aws_vpc_cidr	AWS VPC CIDR — advertised to GCP
aws_subnet_cidr	AWS private subnet for EC2
aws_dx_gateway_asn	Private ASN for the Direct Connect Gateway
gcp_vpc_cidr	GCP subnet CIDR — advertised to AWS

SSH to GCE uses a key pair generated by Terraform (tls_private_key); no variable required.