Syntax looks correct but I get - field not found, node: rfc2136

Traefik Traefik v3 (latest)
1

Hi,

This is my first time setting up Treafik and I’ve definitely jumped in at the deep end. I have 3 hosts running a docker swarm so I am setting Treafik CE up as service. I’ve read that if I want to use ACME certificates I need to use DNS challenges for Traefik when deployed in a swarm. I’m using Technitium as my DNS server and I’ve also read that the only way to use this as my provider when trying to use ACME certs is to set my provider as rfc2136.

Whenever I try to start the service I get “field not found, node: rfc2136”. I’ve had several evenings going around in circles with Gemini for fault finding as I couldn’t find any new pointers in the documentation. To me this sounds like a formatting issue in my config but even after throwing this at a yaml checker and directly pasting config from other sources I still get the error and can’t spot what I should change to accept the rfc2136 provider.

My traefik.yaml certificatesResolvers looks like this and any pointers would be greatly appreciated:

certificatesResolvers:
  stepca:
    acme:
      caServer: "https://myinternalcaserver.lab.env:443/acme/acme/directory"
      email: "test@generic.email"
      storage: "/acme-data/acme.json" 
      dnsChallenge:
        provider: rfc2136
        rfc2136:
          nameserver: "MY.DNS.IP:53" 
          tsigKeyName: "traefik-acme"
          tsigAlgorithm: "hmac-sha256"
          tsigSecret: "MYTSIGKEY"
        resolvers:
          - "MY.DNS.IP:53"
        disablePropagationCheck: true
2

The old doc states to use env vars: RFC2136_TSIG_KEY, RFC2136_TSIG_SECRET, RFC2136_TSIG_ALGORITHM, RFC2136_NAMESERVER