Fix Unable to connect to the server: EOF when Docker Desktop retrieves node status

Preface

When starting a single-node Kubernetes environment using Docker on macOS, when obtaining node status via kubectl, the response Unable to connect to the server: EOF Huh! Docker Desktop shows that the Kubernetes service is starting and there are no issues, but kubectl in the terminal cannot interact with kube-apiserver!

See, Docker Kubernetes is indeed working properly!

Problem manifestations

By executing kubectl get nodes Unable to correctly display Kubernetes node status, and the following error message is returned

Unable to connect to the server: EOF

Problem Analysis

Step 1: View Kubernetes status configuration information

View the current macOS system Kubernetes node configuration information by running the following command.

kubectl config view

The specific configuration is as follows.

apiVersion: v1
clusters:
- cluster:
    certificate-authority-data: DATA+OMITTED
    server: https://kubernetes.docker.internal:6443
  name: docker-desktop
contexts:
- context:
    cluster: docker-desktop
    user: docker-desktop
  name: docker-desktop
current-context: docker-desktop
kind: Config
preferences: {}
users:
- name: docker-desktop
  user:
    client-certificate-data: DATA+OMITTED
    client-key-data: DATA+OMITTED

From the configuration information above, it can be seen that kube-apiserver The access address is https://kubernetes.docker.internal:6443 So when Docker Desktop enables the Kubernetes service, it will definitely ... to /etc/hosts Configuration file write mapping

Step 2: View the /etc/hosts configuration file

# Added by Docker Desktop
# To allow the same kube context to work on the host and the container:
127.0.0.1 	kubernetes.docker.internal
# End of section

Step 3: Disable the proxy and test whether it works normally

kubectl get node

Oh! After turning off the proxy, it can respond normally with Kubernetes node status information.

NAME             STATUS   ROLES           AGE   VERSION
docker-desktop   Ready    control-plane   58m   v1.32.2

Step 4: Add the no_proxy environment variable

To add it temporarily, you only need to run an export command in the current terminal.

export no_proxy=kubernetes.docker.internal

Of course, as a developer, your proxy is basically always on, edit ~/.zshrc or ~/.bash_profile Add the following configuration to export environment variables

export no_proxy=kubernetes.docker.internal

Summary

Proxies are a mixed bag—one wrong move and you fall into a trap!