Add a Zone File to Kubernetes CoreDNS

Internal

• CoreDNS in Kubernetes

Overview

The zone file is added as a ConfigMap entry which will be projected in CoreDNS pods as a file, under the zone file name. The Corefile projected as part of the same ConfigMap should be also modified to refer the new zone file with the "file" directive.

The CoreDNS deployment is then scaled down, the new configuration file is added as an "item" in configMap volume mount, and the deployment is then scaled up.