<p>I have a cluster running on GKE. I have my domain names registered in Cloudflare. </p>

<p>When I add/modify dns entries in Cloudflare, the propagation seems to be very fast (using tools like <a href="https://dnschecker.org/" rel="nofollow noreferrer">https://dnschecker.org/</a>). However in my gke cluster, the pods don't resolve the new entries (I have to wait a long long time...). I have tried to add the dns resolver 1.1.1.1 in my kube-dns pods, then I could resolve the new entries in the kube-dns pods (kubedns and dnsmasq) but it still doesn't work for my other pods (the dnspolicy is correctly set to ClusterFirst).</p>

<p>Thanks for your help.</p>

<p>You can change the DNS upstream nameservers [1] but keep in mind that DNS propagation can take up to 48h. Here is the example from the documentation:</p>

<pre><code>apiVersion: v1
kind: ConfigMap
metadata:
  name: kube-dns
  namespace: kube-system
data:
  upstreamNameservers: |
    ["1.1.1.1"]
</code></pre>

<p>[1] <a href="https://kubernetes.io/docs/tasks/administer-cluster/dns-custom-nameservers/#example-upstream-nameserver" rel="nofollow noreferrer">https://kubernetes.io/docs/tasks/administer-cluster/dns-custom-nameservers/#example-upstream-nameserver</a></p>
