Enabling RFC2136 for ExternalDNS

In order to enable the provider RFC2136 on ExternalDNS, the following rfc2136.* parameters should be changed in the values.yaml of the K8GB helm chart:

• One authentication method should be enabled on the values:

  • Insecure
    • This method doesn't use any authentication and anonymous updates to the DNS records can be executed
  • TSIG
    • This method uses TSIG authentication that relies on a token provided for the DNS records update.
  • GSS-TSIG
    • This method uses GSS-TSIG authentication, which is a variation of the TSIG method, but uses Kerberos for the generation of tokens for authentication and authorization
    • Method used by Active Directory Windows DNS

• GSS-TSIG

  • kerberos-username
    • this key should have the value of a Active Directory user account that has permissions for DNS updates
  • kerberos-password
    • password of the user account that will be used. Be aware that this isn't encrypted and so far ExternalDNS doesn't support adding a Secret reference for this value, so it will be stored in clear text
  • kerberos-realm
    • domain that will be used for authentication of the user

Sample for GSS-TSIG authentication

rfc2136:
  enabled: true
  rfc2136Opts:
    - host: yourAcDc.k8gb.local
    - port: 53
  rfc2136auth:
    insecure:
      enabled: false
    tsig:
      enabled: false
      tsigCreds:
        - tsig-secret-alg: hmac-sha256
        - tsig-keyname: externaldns-key
    gssTsig:
      enabled: true
      gssTsigCreds:
        - kerberos-username: someServiceAccount
        - kerberos-password: insecurePlainTextPassword
        - kerberos-realm: yourKerberosRealm.domain