ExternalDNS Webhook Provider for Mikrotik

Important

While this software has reached version v1.0.0, it has not yet undergone extensive testing in large-scale, real-world environments. As such, it may still have bugs and may not yet be fully suitable for production use.

I encourage users to report any issues or suggest improvements, as this project remains under active development. Thank you for contributing!

ExternalDNS is a Kubernetes add-on for automatically managing DNS records for Kubernetes ingresses and services by using different DNS providers. This webhook provider allows you to automate DNS records from your Kubernetes clusters into your MikroTik router.

Supported DNS record types: A, AAAA, CNAME, MX, NS, SRV, TXT

For examples of creating DNS records either via CRDs or via Ingress/Service annotations, check out the example/ directory.

🎯 Requirements

Note

v0.15.0 of ExternalDNS added support for providerSpecific annotations in Ingress/Service objects for webhook providers.

While older versions of ExternalDNS may work, but support for this feature will not be present.

• ExternalDNS >= v0.15.0
• Mikrotik RouterOS (tested on 7.16 stable)

🚫 Limitations

Multiple Targets

Currently, DNSEndpoints with multiple targets are not supported. No error will be thrown, but only one record will be created with the first target from the list.

This means that when creating a DNSEndpoint like this, only the first of the two targets will be taken into account (i.e. 192.192.192.192).

---
apiVersion: externaldns.k8s.io/v1alpha1
kind: DNSEndpoint
metadata:
  name: a-record
spec:
  endpoints:
    - dnsName: a.example.com
      recordTTL: 3605
      recordType: A
      targets:
        - 192.192.192.192
        - 193.193.193.193

The problem is that the External DNS controller will detect a drift on this and it will continuously attempt to update the DNS record, thus it will constantly send PUT requests to your RouterOS instance on every reconciliation loop.

⚙️ Configuration Options

MikroTik Configuration

Environment Variable	Description	Default Value
MIKROTIK_BASEURL	URL at which the RouterOS API is available. (ex. https://192.168.88.1:443)	N/A
MIKROTIK_USERNAME	Username for the RouterOS API authentication.	N/A
MIKROTIK_PASSWORD	Password for the RouterOS API authentication.	N/A
MIKROTIK_SKIP_TLS_VERIFY	Whether to skip TLS verification (true or false).	false
LOG_FORMAT	The format in which logs will be printed. (text or json)	json
LOG_LEVEL	The verbosity at which logs are printed logs. (debug, info, warn or error)	info

Webhook Server Configuration

Environment Variable	Description	Default Value
SERVER_HOST	The host address where the server listens.	localhost
SERVER_PORT	The port where the server listens.	8888
SERVER_READ_TIMEOUT	Duration the server waits before timing out on read operations.	N/A
SERVER_WRITE_TIMEOUT	Duration the server waits before timing out on write operations.	N/A
DOMAIN_FILTER	List of domains to include in the filter.	Empty
EXCLUDE_DOMAIN_FILTER	List of domains to exclude from filtering.	Empty
REGEXP_DOMAIN_FILTER	Regular expression for filtering domains.	Empty
REGEXP_DOMAIN_FILTER_EXCLUSION	Regular expression for excluding domains from the filter.	Empty

🚀 Deployment

1. Create a service account in RouterOS. This local user needs read and write access to manage static DNS.

2. Create a Kubernetes namespace for your External DNS deployment

   ---
   apiVersion: v1
   kind: Namespace
   metadata:
     name: external-dns

3. Create a Kubernetes secret with the connection details for your RouterOS instance:

   ---
   apiVersion: v1
   kind: Secret
   metadata:
     name: mikrotik-credentials
     namespace: external-dns
   stringData:
     MIKROTIK_BASEURL: "https://192.168.88.1:443"
     MIKROTIK_USERNAME: "external-dns"
     MIKROTIK_PASSWORD: "external-dns"
     MIKROTIK_SKIP_TLS_VERIFY: "true"

4. Add the External DNS helm repository and update your local cache

   helm repo add external-dns https://kubernetes-sigs.github.io/external-dns/
   helm repo update

5. Configure your helm values. Take a look at the example values.yaml

6. Install the External DNS helm chart

   helm upgrade --install --namespace external-dns external-dns external-dns/external-dns -f values.yaml

Tip

By default, support for MX, NS and SRV records is disabled and needs to be enabled via the --managed-record-types argument. Make sure to set --managed-record-types=SRV if you want to enable SRV records, and so on.

⭐ Stargazers

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🤝 Gratitude and Thanks

Thanks to all the people who donate their time to the Home Operations Discord community.