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external-dns

This component creates a Helm deployment for external-dns on a Kubernetes cluster. external-dns is a Kubernetes addon that configures public DNS servers with information about exposed Kubernetes services to make them discoverable.

Usage

Stack Level: Regional

Once the catalog is created, the file can be imported as follows.

import:
- catalog/eks/external-dns
...

The default catalog values e.g. stacks/catalog/eks/external-dns.yaml

components:
terraform:
external-dns:
vars:
enabled: true
name: external-dns
chart: external-dns
chart_repository: https://charts.bitnami.com/bitnami
chart_version: "6.33.0"
create_namespace: true
kubernetes_namespace: external-dns
resources:
limits:
cpu: 200m
memory: 256Mi
requests:
cpu: 100m
memory: 128Mi
# Set this to a unique value to avoid conflicts with other external-dns instances managing the same zones.
# For example, when using blue-green deployment pattern to update EKS cluster.
txt_prefix: ""
# You can use `chart_values` to set any other chart options. Treat `chart_values` as the root of the doc.
# See documentation for latest chart version and list of chart_values: https://artifacthub.io/packages/helm/bitnami/external-dns
#
# # For example
# ---
# chart_values:
# aws:
# batchChangeSize: 1000
chart_values: {}
# Extra hosted zones to lookup and support by component name
dns_components:
- component: dns-primary
- component: dns-delegated
- component: dns-delegated/abc
- component: dns-delegated/123
environment: "gbl" # Optional (default "gbl")

Variables

Required Variables

chart (string) required

Chart name to be installed. The chart name can be local path, a URL to a chart, or the name of the chart if repository is specified. It is also possible to use the <repository>/<chart> format here if you are running Terraform on a system that the repository has been added to with helm repo add but this is not recommended.

chart_repository (string) required

Repository URL where to locate the requested chart.

kubernetes_namespace (string) required

The namespace to install the release into.

region (string) required

AWS Region.

Optional Variables

atomic (bool) optional

If set, installation process purges chart on fail. The wait flag will be set automatically if atomic is used.


Default value: true

chart_description (string) optional

Set release description attribute (visible in the history).


Default value: null

chart_values (any) optional

Addition map values to yamlencode as helm_release values.


Default value: { }

chart_version (string) optional

Specify the exact chart version to install. If this is not specified, the latest version is installed.


Default value: null

cleanup_on_fail (bool) optional

Allow deletion of new resources created in this upgrade when upgrade fails.


Default value: true

crd_enabled (bool) optional

Install and use the integrated DNSEndpoint CRD.


Default value: false

create_namespace (bool) optional

Create the namespace if it does not yet exist. Defaults to false.


Default value: null

dns_components optional

A list of additional DNS components to search for ZoneIDs


Type:

list(object({
component = string,
environment = optional(string)
}))

Default value: [ ]

dns_gbl_delegated_environment_name (string) optional

The name of the environment where global dns_delegated is provisioned


Default value: "gbl"

dns_gbl_primary_environment_name (string) optional

The name of the environment where global dns_primary is provisioned


Default value: "gbl"

eks_component_name (string) optional

The name of the eks component


Default value: "eks/cluster"

helm_manifest_experiment_enabled (bool) optional

Enable storing of the rendered manifest for helm_release so the full diff of what is changing can been seen in the plan


Default value: false

istio_enabled (bool) optional

Add istio gateways to monitored sources.


Default value: false

kube_data_auth_enabled (bool) optional

If true, use an aws_eks_cluster_auth data source to authenticate to the EKS cluster.
Disabled by kubeconfig_file_enabled or kube_exec_auth_enabled.



Default value: false

kube_exec_auth_aws_profile (string) optional

The AWS config profile for aws eks get-token to use


Default value: ""

kube_exec_auth_aws_profile_enabled (bool) optional

If true, pass kube_exec_auth_aws_profile as the profile to aws eks get-token


Default value: false

kube_exec_auth_enabled (bool) optional

If true, use the Kubernetes provider exec feature to execute aws eks get-token to authenticate to the EKS cluster.
Disabled by kubeconfig_file_enabled, overrides kube_data_auth_enabled.



Default value: true

kube_exec_auth_role_arn (string) optional

The role ARN for aws eks get-token to use


Default value: ""

kube_exec_auth_role_arn_enabled (bool) optional

If true, pass kube_exec_auth_role_arn as the role ARN to aws eks get-token


Default value: true

kubeconfig_context (string) optional

Context to choose from the Kubernetes config file.
If supplied, kubeconfig_context_format will be ignored.



Default value: ""

kubeconfig_context_format (string) optional

A format string to use for creating the kubectl context name when
kubeconfig_file_enabled is true and kubeconfig_context is not supplied.
Must include a single %s which will be replaced with the cluster name.



Default value: ""

kubeconfig_exec_auth_api_version (string) optional

The Kubernetes API version of the credentials returned by the exec auth plugin


Default value: "client.authentication.k8s.io/v1beta1"

kubeconfig_file (string) optional

The Kubernetes provider config_path setting to use when kubeconfig_file_enabled is true


Default value: ""

kubeconfig_file_enabled (bool) optional

If true, configure the Kubernetes provider with kubeconfig_file and use that kubeconfig file for authenticating to the EKS cluster


Default value: false

metrics_enabled (bool) optional

Whether or not to enable metrics in the helm chart.


Default value: false

policy (string) optional

Modify how DNS records are synchronized between sources and providers (options: sync, upsert-only)


Default value: "sync"

publish_internal_services (bool) optional

Allow external-dns to publish DNS records for ClusterIP services


Default value: true

rbac_enabled (bool) optional

Service Account for pods.


Default value: true

resources optional

The cpu and memory of the deployment's limits and requests.


Type:

object({
limits = object({
cpu = string
memory = string
})
requests = object({
cpu = string
memory = string
})
})

Default value:

{
"limits": {
"cpu": "200m",
"memory": "256Mi"
},
"requests": {
"cpu": "100m",
"memory": "128Mi"
}
}
timeout (number) optional

Time in seconds to wait for any individual kubernetes operation (like Jobs for hooks). Defaults to 300 seconds


Default value: null

txt_prefix (string) optional

Prefix to create a TXT record with a name following the pattern prefix.<CNAME record>.


Default value: "external-dns"

wait (bool) optional

Will wait until all resources are in a ready state before marking the release as successful. It will wait for as long as timeout. Defaults to true.


Default value: null

Context Variables

The following variables are defined in the context.tf file of this module and part of the terraform-null-label pattern.

additional_tag_map (map(string)) optional

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.


Required: No

Default value: { }

attributes (list(string)) optional

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.


Required: No

Default value: [ ]

context (any) optional

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.


Required: No

Default value:

{
"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
}
delimiter (string) optional

Delimiter to be used between ID elements.
Defaults to - (hyphen). Set to "" to use no delimiter at all.


Required: No

Default value: null

descriptor_formats (any) optional

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).


Required: No

Default value: { }

enabled (bool) optional

Set to false to prevent the module from creating any resources
Required: No

Default value: null

environment (string) optional

ID element. Usually used for region e.g. 'uw2', 'us-west-2', OR role 'prod', 'staging', 'dev', 'UAT'
Required: No

Default value: null

id_length_limit (number) optional

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.


Required: No

Default value: null

label_key_case (string) optional

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.


Required: No

Default value: null

label_order (list(string)) optional

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.


Required: No

Default value: null

label_value_case (string) optional

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.


Required: No

Default value: null

labels_as_tags (set(string)) optional

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.


Required: No

Default value:

[
"default"
]
name (string) optional

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.


Required: No

Default value: null

namespace (string) optional

ID element. Usually an abbreviation of your organization name, e.g. 'eg' or 'cp', to help ensure generated IDs are globally unique
Required: No

Default value: null

regex_replace_chars (string) optional

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.


Required: No

Default value: null

stage (string) optional

ID element. Usually used to indicate role, e.g. 'prod', 'staging', 'source', 'build', 'test', 'deploy', 'release'
Required: No

Default value: null

tags (map(string)) optional

Additional tags (e.g. {'BusinessUnit': 'XYZ'}).
Neither the tag keys nor the tag values will be modified by this module.


Required: No

Default value: { }

tenant (string) optional

ID element (Rarely used, not included by default). A customer identifier, indicating who this instance of a resource is for
Required: No

Default value: null

Outputs

metadata

Block status of the deployed release

Dependencies

Requirements

  • terraform, version: >= 1.0.0
  • aws, version: >= 4.9.0
  • helm, version: >= 2.0
  • kubernetes, version: >= 2.7.1, != 2.21.0

Providers

  • aws, version: >= 4.9.0

Modules

NameVersionSourceDescription
additional_dns_components1.5.0cloudposse/stack-config/yaml//modules/remote-staten/a
dns_gbl_delegated1.5.0cloudposse/stack-config/yaml//modules/remote-staten/a
dns_gbl_primary1.5.0cloudposse/stack-config/yaml//modules/remote-staten/a
eks1.5.0cloudposse/stack-config/yaml//modules/remote-staten/a
external_dns0.10.0cloudposse/helm-release/awsn/a
iam_roleslatest../../account-map/modules/iam-rolesn/a
this0.25.0cloudposse/label/nulln/a

Resources

The following resources are used by this module:

Data Sources

The following data sources are used by this module:

References