README.md

January 1, 2026 · View on GitHub

This component is responsible for provisioning an EFS Network File System with KMS encryption-at-rest. EFS is an excellent choice as the default block storage for EKS clusters so that volumes are not zone-locked.

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Usage

Stack Level: Regional

Here's an example snippet for how to use this component.

components:
  terraform:
    efs:
      vars:
        enabled: true
        name: shared-files
        dns_name: shared-files
        provisioned_throughput_in_mibps: 10
      # additional_security_group_rules:
      #   - key: "fargate_efs"
      #     type: "ingress"
      #     from_port: 2049
      #     to_port: 2049
      #     protocol: "tcp"
      #     description: "Allow Fargate EFS Volume mounts"
      #     cidr_blocks: ["0.0.0.0/0"]

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.

Requirements

Name	Version
terraform	>= 1.0.0
aws	>= 4.0, < 6.0.0

Providers

Name	Version
aws	>= 4.0, < 6.0.0

Modules

Name	Source	Version
efs	cloudposse/efs/aws	1.3.0
eks	cloudposse/stack-config/yaml//modules/remote-state	1.8.0
gbl_dns_delegated	cloudposse/stack-config/yaml//modules/remote-state	1.8.0
iam_roles	../account-map/modules/iam-roles	n/a
kms_key_efs	cloudposse/kms-key/aws	0.12.2
this	cloudposse/label/null	0.25.0
vpc	cloudposse/stack-config/yaml//modules/remote-state	1.8.0

Resources

Name	Type
aws_caller_identity.current	data source
aws_iam_policy_document.kms_key_efs	data source
aws_partition.current	data source

Inputs

Name	Description	Type	Default	Required
additional_security_group_rules	A list of Security Group rule objects to add to the created security group, in addition to the ones this module normally creates. (To suppress the module's rules, set `create_security_group` to false and supply your own security group via `associated_security_group_ids`.) The keys and values of the objects are fully compatible with the `aws_security_group_rule` resource, except for `security_group_id` which will be ignored, and the optional "key" which, if provided, must be unique and known at "plan" time. To get more info see https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule .	`list(any)`	`[]`	no
additional_tag_map	Additional 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.	`map(string)`	`{}`	no
attributes	ID 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.	`list(string)`	`[]`	no
context	Single 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.	`any`	{ "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": [ "unset" ], "name": null, "namespace": null, "regex_replace_chars": null, "stage": null, "tags": {}, "tenant": null }	no
delimiter	Delimiter to be used between ID elements. Defaults to `-` (hyphen). Set to `""` to use no delimiter at all.	`string`	`null`	no
descriptor_formats	Describe 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).	`any`	`{}`	no
efs_backup_policy_enabled	If `true`, automatic backups will be enabled.	`bool`	`false`	no
eks_component_names	The names of the eks components	`set(string)`	[ "eks/cluster" ]	no
eks_security_group_enabled	Use the eks default security group	`bool`	`false`	no
enabled	Set to false to prevent the module from creating any resources	`bool`	`null`	no
environment	ID element. Usually used for region e.g. 'uw2', 'us-west-2', OR role 'prod', 'staging', 'dev', 'UAT'	`string`	`null`	no
hostname_template	The `format()` string to use to generate the hostname via `format(var.hostname_template, var.tenant, var.stage, var.environment)`" Typically something like `"echo.%[3]v.%[2]v.example.com"`.	`string`	n/a	yes
id_length_limit	Limit `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`.	`number`	`null`	no
label_key_case	Controls 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`.	`string`	`null`	no
label_order	The 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.	`list(string)`	`null`	no
label_value_case	Controls 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`.	`string`	`null`	no
labels_as_tags	Set 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. Notes: 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.	`set(string)`	[ "default" ]	no
name	ID 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.	`string`	`null`	no
namespace	ID element. Usually an abbreviation of your organization name, e.g. 'eg' or 'cp', to help ensure generated IDs are globally unique	`string`	`null`	no
performance_mode	The file system performance mode. Can be either `generalPurpose` or `maxIO`	`string`	`"generalPurpose"`	no
provisioned_throughput_in_mibps	The throughput, measured in MiB/s, that you want to provision for the file system. Only applicable with `throughput_mode` set to provisioned	`number`	`0`	no
regex_replace_chars	Terraform 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.	`string`	`null`	no
region	AWS Region	`string`	n/a	yes
stage	ID element. Usually used to indicate role, e.g. 'prod', 'staging', 'source', 'build', 'test', 'deploy', 'release'	`string`	`null`	no
tags	Additional tags (e.g. `{'BusinessUnit': 'XYZ'}`). Neither the tag keys nor the tag values will be modified by this module.	`map(string)`	`{}`	no
tenant	ID element _(Rarely used, not included by default)_. A customer identifier, indicating who this instance of a resource is for	`string`	`null`	no
throughput_mode	Throughput mode for the file system. Defaults to bursting. Valid values: `bursting`, `provisioned`. When using `provisioned`, also set `provisioned_throughput_in_mibps`	`string`	`"bursting"`	no

Outputs

Name	Description
efs_arn	EFS ARN
efs_dns_name	EFS DNS name
efs_host	DNS hostname for the EFS
efs_id	EFS ID
efs_mount_target_dns_names	List of EFS mount target DNS names
efs_mount_target_ids	List of EFS mount target IDs (one per Availability Zone)
efs_mount_target_ips	List of EFS mount target IPs (one per Availability Zone)
efs_network_interface_ids	List of mount target network interface IDs
security_group_arn	EFS Security Group ARN
security_group_id	EFS Security Group ID
security_group_name	EFS Security Group name

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

References

For additional context, refer to some of these links.

cloudposse-terraform-components - Cloud Posse's upstream component

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✨ Contributing

This project is under active development, and we encourage contributions from our community.

Many thanks to our outstanding contributors:

For 🐛 bug reports & feature requests, please use the issue tracker.

In general, PRs are welcome. We follow the typical "fork-and-pull" Git workflow.

Review our Code of Conduct and Contributor Guidelines.
Fork the repo on GitHub
Clone the project to your own machine
Commit changes to your own branch
Push your work back up to your fork
Submit a Pull Request so that we can review your changes

NOTE: Be sure to merge the latest changes from "upstream" before making a pull request!

Running Terraform Tests

We use Atmos to streamline how Terraform tests are run. It centralizes configuration and wraps common test workflows with easy-to-use commands.

All tests are located in the test/ folder.

Under the hood, tests are powered by Terratest together with our internal Test Helpers library, providing robust infrastructure validation.

Setup dependencies:

Install Atmos (installation guide)
Install Go 1.24+ or newer
Install Terraform or OpenTofu

To run tests:

Run all tests:
```
atmos test run
```
Clean up test artifacts:
```
atmos test clean
```
Explore additional test options:
```
atmos test --help
```

The configuration for test commands is centrally managed. To review what's being imported, see the atmos.yaml file.

Learn more about our automated testing in our documentation or implementing custom commands with atmos.

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License

Preamble to the Apache License, Version 2.0

Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

  https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.

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