Essential DNS Tools for Kubernetes CoreDNS and ExternalDNS

How CoreDNS and ExternalDNS Work Together in Kubernetes for Seamless DNS Management

Introduction

CoreDNS and ExternalDNS are two essential components commonly used in Kubernetes clusters for DNS management. They serve different purposes but can work together to provide a seamless DNS experience in a Kubernetes environment. Here’s an overview of each and how they can be used together:

CoreDNS

CoreDNS is the default DNS server for Kubernetes. It is responsible for service discovery within the cluster. CoreDNS translates Kubernetes Service names into IP addresses, allowing pods to communicate with each other using service names.

Key Functions of CoreDNS:

• Service Discovery: Resolves internal Kubernetes service names to their corresponding ClusterIP.
• Pod DNS: Resolves pod names to their IP addresses within the cluster.
• Custom DNS Configuration: Can be configured to forward DNS queries to external DNS servers or provide custom DNS zones.

CoreDNS Configuration Example:

The CoreDNS configuration is typically found in the ConfigMap associated with the…