This component creates a Transit Gateway VPC Attachment and optionally creates an association with a Transit Gateway Route Table.
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Stack Level: Regional
Here's an example snippet for how to use this component.
components:
terraform:
tgw/attachment:
vars:
enabled: true
transit_gateway_id: !terraform.output tgw/hub core-use1-network transit_gateway_id
transit_gateway_route_table_id: !terraform.output tgw/hub core-use1-network transit_gateway_route_table_id
create_transit_gateway_route_table_association: falseIn the primary account, the account that has the Transit Gateway and the Transit Gateway Route Table, we need to create an association with the Transit Gateway Route Table. This is necessary for attachments to connect to the Transit Gateway Route Table. For example, if you have a Transit Gateway Route Table in the core-network account, you will need to create an association for each VPCs connected to that Transit Gateway Route Table.
The intention is to have all configuration for a given account in the same stack as that account. For example, since the Transit Gateway Route Table is in the core-network account, we would create all necessary associations in the core-network account.
# core-network stack
components:
terraform:
tgw/attachment:
vars:
enabled: true
transit_gateway_id: !terraform.output tgw/hub core-usw2-network transit_gateway_id
transit_gateway_route_table_id: !terraform.output tgw/hub core-usw2-network transit_gateway_route_table_id
# Add an association for this account itself
create_transit_gateway_route_table_association: true
# Include association for each of the connected accounts, if necessary
additional_associations:
- attachment_id: !terraform.output tgw/attachment plat-usw2-dev transit_gateway_attachment_id
route_table_id: !terraform.output tgw/hub transit_gateway_route_table_id
- attachment_id: !terraform.output tgw/attachment plat-usw2-prod transit_gateway_attachment_id
route_table_id: !terraform.output tgw/hub transit_gateway_route_table_idIn connected accounts, an account that does not have a Transit Gateway and Transit Gateway Route Table, you do not need to create any associations.
# plat-dev stack
components:
terraform:
tgw/attachment:
vars:
enabled: true
transit_gateway_id: !terraform.output tgw/hub core-usw2-network transit_gateway_id
transit_gateway_route_table_id: !terraform.output tgw/hub core-usw2-network transit_gateway_route_table_id
# Do not create an association in this account since there is no Transit Gateway Route Table in this account.
create_transit_gateway_route_table_association: falsePlus the same for all other connected accounts.
Important
In Cloud Posse's examples, we avoid pinning modules to specific versions to prevent discrepancies between the documentation and the latest released versions. However, for your own projects, we strongly advise pinning each module to the exact version you're using. This practice ensures the stability of your infrastructure. Additionally, we recommend implementing a systematic approach for updating versions to avoid unexpected changes.
No requirements.
No providers.
No modules.
No resources.
No inputs.
No outputs.
Check out these related projects.
- Cloud Posse Terraform Modules - Our collection of reusable Terraform modules used by our reference architectures.
- Atmos - Atmos is like docker-compose but for your infrastructure
For additional context, refer to some of these links.
- Cloud Posse Documentation - Complete documentation for the Cloud Posse solution
- Reference Architectures - Launch effortlessly with our turnkey reference architectures, built either by your team or ours.
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