update

kubernetes/kubernetes-dns.md

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+# Kubernetes DNS
+
+## DNS for Services and Pods
+
+Kubernetes creates DNS records for Services and Pods. You can contact Services with consistent DNS names instead of IP addresses.
+
+```
+your-service.your-namespace.svc.cluster.local
+```
+
+Any Pods exposed by a Service have the following DNS resolution available:
+
+```
+your-prod.your-service.your-namespace.svc.cluster.local
+```
+
+---
+## Custom DNS Settings
+
+### Edit coredns config map
+
+Add entry to the `Corefile: |` section of the `configmap/coredns` in section **kube-system**.
+
+```yml
+.:53 {
+  # ...
+}
+import /etc/coredns/custom/*.server
+```
+
+### Add new config map
+
+Example for local DNS server using the **clcreative.home** zone.
+
+```yml
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: coredns-custom
+  namespace: kube-system
+data:
+  clcreative.server: |
+    clcreative.home:53 {
+      forward . 10.20.0.10
+    }
+```