Shared VPC where Attached Projects Can Actually Use a Subnet
Attaching a service project is the visible half: its instances land in a shared subnet only when the creating principal holds networkUser on that subnet, and for GKE, Cloud Run or Dataflow that principal is the service agent, not a person. Takes the per-subnet grants with the attachments, refuses a project attached with none, and adds the host-level grant GKE needs.
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 2026-09-14 · how we verify
Use it from the registry
terraform · opentofumodule "shared_vpc" {
source = "www.iac-bazaar.com/iac-bazaar/gcp-shared-vpc/gcp"
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.
Inputs & outputs
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Documentation
gcp-shared-vpc
Shared VPC: a host project, the service projects attached to it, and the
subnet grants without which attaching means nothing. Works with Terraform
and OpenTofu (>= 1.6), google provider >= 6.0, < 7.0.
An attached service project with no subnet grant can use no subnet.
Instances land in a shared subnet only when the creating principal holds
roles/compute.networkUser on that subnet - and for GKE, Cloud Run or
Dataflow the principal is the service's own agent account. This module takes
the grants with the attachments and refuses a service project with none
unless accept_unusable_attachment.
networkUser on the host project is every subnet. Per subnet here.
GKE needs one more grant: roles/container.hostServiceAgentUser on the
host for each cluster project's service agent. gke_service_agents takes
them.
Verification
Static validation runs tofu fmt, init, validate, tflint and checkov.
This module has not yet had a live test, so it is published as statically
validated with its live test pending and does not carry the live-tested mark.
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
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