> For the complete documentation index, see [llms.txt](https://docs.ionos.com/cloud/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.ionos.com/cloud/~/revisions/1AlFSZBNMIBgs7fiOwFD/managed-services/managed-kubernetes/add-custom-coredns-configuration.md).

# Add Custom CoreDNS Configuration

It may be desirable to enhance the configuration of CoreDNS by incorporating additional settings. To ensure the persistence of these changes during control plane maintenance, it is necessary to create a ConfigMap within the `kube-system` namespace. The ConfigMap should be named `coredns-additional-conf` and should include a data entry with the key `extra.conf`. The value associated with this entry must be a string that encompasses the supplementary configuration.

Below is an illustrative example that demonstrates the process of adding a custom DNS entry for `example.abc`:

```yaml
apiVersion: v1
kind: ConfigMap
metadata:
  name: coredns-additional-conf
  namespace: kube-system
data:
    extra.conf: |
      example.abc:53 {
        hosts {
          1.2.3.4 example.abc
          2.3.4.5 server.example.abc
          fallthrough
        }
      }
```


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