diff --git a/README.md b/README.md
index e76279b..54d3a63 100644
--- a/README.md
+++ b/README.md
@@ -27,6 +27,7 @@ Kubernetes is an open‑source platform that automates the deployment, scaling,
   - [Inline with heredoc and environment variables](#inline-with-heredoc-and-environment-variables)
   - [substr](#substr)
 - [service accounts](#service-accounts)
+- [core-dns](#core-dns)
 
 ## k3s
 
@@ -362,3 +363,28 @@ envsubst < ./secret.yaml | kubectl apply -f -
 ```bash
 kubectl get secret continuous-deploy -o jsonpath='{.data.token}' | base64 -d
 ```
+
+## core-dns
+
+Remove warning from logs.
+
+```log
+[WARNING] No files matching import glob pattern: /etc/coredns/custom/*.server
+[WARNING] No files matching import glob pattern: /etc/coredns/custom/*.override
+```
+
+1. Apply on kubernetes
+
+```yaml
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: coredns-custom
+  namespace: kube-system
+data:
+  log.override: |
+    #
+  stub.server: |
+    #
+
+```