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Component: cross-region-hub-connector

This component is responsible for provisioning an AWS Transit Gateway Peering Connection to connect TGWs from different accounts and(or) regions.

Transit Gateway does not support sharing the Transit Gateway hub across regions. You must deploy a Transit Gateway hub for each region and connect the alternate hub to the primary hub.


Stack Level: Regional

This component is deployed to each alternate region with tgw/hub.

For example if your primary region is us-east-1 and your alternate region is us-west-2, deploy another tgw/hub in us-west-2 and peer the two with tgw/cross-region-hub-connector with the following stack config, imported into us-west-2

- catalog/tgw/hub

# Cross region TGW requires additional hub in the alternate region
# These are all connections available for spokes in this region
# Defaults environment to this region
# Hub for this region is always required
- account:
tenant: core
stage: network
# VPN source
- account:
tenant: core
stage: network
environment: use1
# Github Runners
- account:
tenant: core
stage: auto
environment: use1
- eks/cluster
# All stacks where a spoke will be deployed
- account:
tenant: plat
stage: dev
eks_component_names: [] # Add clusters here once deployed

# This alternate hub needs to be connected to the primary region's hub
enabled: true
primary_tgw_hub_region: us-east-1


terraform>= 1.0.0
aws>= 4.1
utils>= 1.10.0


aws>= 4.1
aws.primary_tgw_hub_region>= 4.1






account_map_environment_nameThe name of the environment where account_map is provisionedstring"gbl"no
account_map_stage_nameThe name of the stage where account_map is provisionedstring"root"no
additional_tag_mapAdditional key-value pairs to add to each map in tags_as_list_of_maps. Not added to tags or id.
This is for some rare cases where resources want additional configuration of tags
and therefore take a list of maps with tag key, value, and additional configuration.
attributesID element. Additional attributes (e.g. workers or cluster) to add to id,
in the order they appear in the list. New attributes are appended to the
end of the list. The elements of the list are joined by the delimiter
and treated as a single ID element.
contextSingle object for setting entire context at once.
See description of individual variables for details.
Leave string and numeric variables as null to use default value.
Individual variable settings (non-null) override settings in context object,
except for attributes, tags, and additional_tag_map, which are merged.
"additional_tag_map": {},
"attributes": [],
"delimiter": null,
"descriptor_formats": {},
"enabled": true,
"environment": null,
"id_length_limit": null,
"label_key_case": null,
"label_order": [],
"label_value_case": null,
"labels_as_tags": [
"name": null,
"namespace": null,
"regex_replace_chars": null,
"stage": null,
"tags": {},
"tenant": null
delimiterDelimiter to be used between ID elements.
Defaults to - (hyphen). Set to "" to use no delimiter at all.
descriptor_formatsDescribe additional descriptors to be output in the descriptors output map.
Map of maps. Keys are names of descriptors. Values are maps of the form
{<br/> format = string<br/> labels = list(string)<br/>}
(Type is any so the map values can later be enhanced to provide additional options.)
format is a Terraform format string to be passed to the format() function.
labels is a list of labels, in order, to pass to format() function.
Label values will be normalized before being passed to format() so they will be
identical to how they appear in id.
Default is {} (descriptors output will be empty).
enabledSet to false to prevent the module from creating any resourcesboolnullno
env_naming_conventionThe cloudposse/utils naming convention used to translate environment name to AWS region name. Options are to_short and to_fixedstring"to_short"no
environmentID element. Usually used for region e.g. 'uw2', 'us-west-2', OR role 'prod', 'staging', 'dev', 'UAT'stringnullno
id_length_limitLimit id to this many characters (minimum 6).
Set to 0 for unlimited length.
Set to null for keep the existing setting, which defaults to 0.
Does not affect id_full.
label_key_caseControls the letter case of the tags keys (label names) for tags generated by this module.
Does not affect keys of tags passed in via the tags input.
Possible values: lower, title, upper.
Default value: title.
label_orderThe order in which the labels (ID elements) appear in the id.
Defaults to ["namespace", "environment", "stage", "name", "attributes"].
You can omit any of the 6 labels ("tenant" is the 6th), but at least one must be present.
label_value_caseControls the letter case of ID elements (labels) as included in id,
set as tag values, and output by this module individually.
Does not affect values of tags passed in via the tags input.
Possible values: lower, title, upper and none (no transformation).
Set this to title and set delimiter to "" to yield Pascal Case IDs.
Default value: lower.
labels_as_tagsSet of labels (ID elements) to include as tags in the tags output.
Default is to include all labels.
Tags with empty values will not be included in the tags output.
Set to [] to suppress all generated tags.
The value of the name tag, if included, will be the id, not the name.
Unlike other null-label inputs, the initial setting of labels_as_tags cannot be
changed in later chained modules. Attempts to change it will be silently ignored.
nameID element. Usually the component or solution name, e.g. 'app' or 'jenkins'.
This is the only ID element not also included as a tag.
The "name" tag is set to the full id string. There is no tag with the value of the name input.
namespaceID element. Usually an abbreviation of your organization name, e.g. 'eg' or 'cp', to help ensure generated IDs are globally uniquestringnullno
primary_tgw_hub_regionThe name of the AWS region where the primary Transit Gateway hub is deployed. This value is used with var.env_naming_convention to determine the primary Transit Gateway hub's environment name.stringn/ayes
primary_tgw_hub_stageThe name of the stage where the primary Transit Gateway hub is deployed. Defaults to module.this.stagestring""no
primary_tgw_hub_tenantThe name of the tenant where the primary Transit Gateway hub is deployed. Only used if tenants are deployed and defaults to module.this.tenantstring""no
regex_replace_charsTerraform regular expression (regex) string.
Characters matching the regex will be removed from the ID elements.
If not set, "/[^a-zA-Z0-9-]/" is used to remove all characters other than hyphens, letters and digits.
regionAWS Regionstringn/ayes
stageID element. Usually used to indicate role, e.g. 'prod', 'staging', 'source', 'build', 'test', 'deploy', 'release'stringnullno
tagsAdditional tags (e.g. {'BusinessUnit': 'XYZ'}).
Neither the tag keys nor the tag values will be modified by this module.
tenantID element _(Rarely used, not included by default)_. A customer identifier, indicating who this instance of a resource is forstringnullno


aws_ec2_transit_gateway_peering_attachment_idTransit Gateway Peering Attachment ID