Transit Gateway Hub with Explicit Routing
Hub-and-spoke Transit Gateway with its own route tables, VPC attachments, static and blackhole routes, and RAM sharing. Default route table association and propagation are off, so an attachment joins a routing domain because you said so rather than by default.
Verification
Static-verifiedPassed: validated and lint-clean (provider-schema-validated for AWS/Azure/GCP; Terraform-language lint elsewhere).
Conformance
- Static validation (fmt · validate · tflint)
- Security scan clean (Checkov)
- Plan tests (mocked: validation rules · outputs)
Provenance
- SHA-256 checksum
- Signature (pending)
Functional
- Live test pending (no cloud run yet)
Last verified 2026-09-12 · how we verify
Use it from the registry
terraform · opentofumodule "transit_gateway" {
source = "www.iac-bazaar.com/iac-bazaar/aws-transit-gateway/aws"
version = "1.0.0"
}Needs a registry token from /account/tokens. The module itself is free; the account is what identifies you. Full setup: registry docs.
Cite it in your README
badge · attributionPaste this beside the module in the repository that uses it. The badge is rendered from this artifact's verification record, so it reads static-verified because the record says so, and the link lands on this page.
[](https://www.iac-bazaar.com/catalog/aws-transit-gateway?utm_source=syndication&utm_medium=readme&utm_campaign=artifact)
Terraform module 1.0.0, static-verified on IaC Bazaar: [Transit Gateway Hub with Explicit Routing](https://www.iac-bazaar.com/catalog/aws-transit-gateway?utm_source=syndication&utm_medium=readme&utm_campaign=artifact)
```hcl
module "transit_gateway" {
source = "www.iac-bazaar.com/iac-bazaar/aws-transit-gateway/aws"
version = "1.0.0"
}
```Preview:
Inputs & outputs
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Documentation
aws-transit-gateway
Transit Gateway hub with explicit route tables, VPC attachments, static and
blackhole routes, and optional RAM sharing across an AWS Organization. Works
with Terraform and OpenTofu (>= 1.6), AWS provider >= 6.0, < 7.0.
The gotcha this module exists to remove: a Transit Gateway created with its default route table association and propagation left on puts every attachment into one routing domain, so any VPC can reach any other the moment it attaches. Nothing errors when that happens - routes simply appear - which is why it ships to production so often. Here the defaults are off and every association is something you wrote down.
Secure defaults:
- Default route table association and propagation disabled, on the gateway and again on each attachment
- Attachment requests from shared accounts are not auto-accepted: an attachment is a route into your network
- RAM shares refuse external principals; sharing reaches your organization or an OU, not the internet
- Association and propagation are separate inputs, because what an attachment can REACH and who can reach IT are different decisions
Verification
Static validation runs tofu fmt, init, validate, tflint and checkov.
This module has not yet had a live test: creating a Transit Gateway and
attaching VPCs bills per attachment-hour, so it is published as statically
validated with its live test pending, and the catalog says exactly that. It
does not carry the live-tested mark and will not until a real
apply -> verify -> destroy has run with confirmed teardown.
Usage code & full reference need an account
The complete copy-paste usage, the full input/output reference, and operational notes are free with an account - shown here and bundled in the download. Sign in and this section fills in.
- Usage
- Routing model
- Inputs, outputs
Related modules
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