external-dns.md

ExternalDNS configuration reference for Lokomotive

Contents

• Introduction
• Prerequisites
• Configuration
• Attribute reference
• Applying
• Destroying

Introduction

ExternalDNS is a Kubernetes addon that synchronizes exposed Kubernetes Services and Ingresses with DNS providers to make them discoverable.

Prerequisites

• A Lokomotive cluster accessible via kubectl.

• An ingress controller such as Contour for HTTP ingress.

Configuration

ExternalDNS component with Contour supports managing DNS records for Services of type LoadBalancer only. More information on this limitation is explained in this issue.

ExternalDNS component currently supports AWS Route53 DNS provider.

ExternalDNS component configuration example:

component "external-dns" {
  # Required arguments.
  aws {
    # Required arguments
    zone_type = "public"
    zone_id = "ZQXH02G1EPZ6R"
    # Optional arguments.
    aws_access_key_id = ""
    aws_secret_access_key = ""
  }

  # Optional arguments.
  sources = ["service"]
  namespace = "external-dns"
  policy = "upsert-only"
  metrics = false
}

ExternalDNS manages DNS entries for the values in the field ingress_hosts of the Contour component.

Attribute reference

Table of all the arguments accepted by the component.

Example:

Argument	Description	Default	Required
sources	Kubernetes resources type to be observed for new DNS entries by ExternalDNS.	["service"]	false
namespace	Namespace to install ExternalDNS.	"external-dns"	false
policy	Modify how DNS records are sychronized between sources and providers (options: sync, upsert-only).	"upsert-only"	false
metrics	Enable metrics collection by Prometheus. Needs Prometheus Operator component installed.	false	false
aws	Configuration block for AWS Route53 DNS provider.	-	true
aws.zone_type	Filter for zones of this type (options: public, private).	"public"	false
aws.zone_id	ID of the DNS zone.	-	true
aws.aws_access_key_id	AWS access key ID for AWS credentials. Use environment variable AWS_ACCESS_KEY_ID instead.	-	false
aws.aws_secret_access_key	AWS secret access key for AWS credentials. Use environment variable AWS_SECRET_ACCESS_KEY instead.	-	false

Applying

To apply the ExternalDNS component:

lokoctl component apply external-dns

Destroying

To destroy the component:

lokoctl component render-manifest external-dns | kubectl delete -f -