<p>I've built 3 nodes on linux academy. On the control plane I can see 3 nodes running. On either of the two worker nodes I try to run <code>kubectl get nodes</code>. Initially I was prompted that <code>KUBERNETES_MASTER</code> was not set. </p>

<p>Inside the worker nodes, I've tried setting this to the server value found in <code>/kube/config</code> in master. So in worker node: <code>export KUBERNETES_MASTER=https://1.2.3.4:6443</code>. When I try this and then try again <code>kubectl get nodes</code> I get <code>Unable to connect to the server: x509: certificate signed by unknown authority</code></p>

<p>I've also tried setting to <code>export KUBERNETES_MASTER=https://kubernetes.default.svc</code> in the worker nodes. When I try this and then try <code>kubectl get nodes</code> I get <code>Unable to connect to the server: dial tcp: lookup kubernetes.default.svc on 127.0.0.53:53: no such host</code></p>

<p>Any idea what I'm doing wrong?</p>

<p>You can only use cluster DNS names from inside pods, not from the nodes directly. As for the cert issue, your kube config file will generally include the CA used for API TLS.</p>
