KinD only exposes the DNS **UDP** port `30053`. The **TCP** port `30054` is not mapped.

[leuwen-lc]

Impact (on Ubuntu 24.04)

Running:

resolvectl query okdp-ui.okdp.sandbox

does not return and prints logs such as:

• Using degraded feature set TCP instead of UDP ...
• Using degraded feature set UDP instead of TCP ...

systemd-resolved performs a feature negotiation (EDNS probe): it tries UDP, may fall back to TCP, but if TCP is not mapped it keeps retrying until it times out.

This situation may also occur with other DNS resolutions.

Proposed solution

Update the KinD configuration in README.md to add the TCP port mapping.

kind: Cluster
apiVersion: kind.x-k8s.io/v1alpha4
name: okdp-sandbox
nodes:
  - role: control-plane
    extraPortMappings:
      - containerPort: 30080
        hostPort: 80
      - containerPort: 30443
        hostPort: 443
      - containerPort: 30053
        hostPort: 30053
        protocol: UDP
      - containerPort: 30054
        hostPort: 30053
        protocol: TCP