Scale the Internet with DNS: A CoreDNS Deep Dive

The presentation discusses the relevance of DNS in Kubernetes clusters and the ways to contribute to the coding community.

• DNS is still relevant in Kubernetes clusters even with software-defined networking
• Contributing to the coding community can be done through GitHub, adding company name to adopt the project, and becoming a maintainer
• SDN allows for more flexibility in assigning IP addresses in a cluster

The speaker mentioned that even with SDN, DNS is still important because it provides an indirection that can be easily changed compared to changing the SDN configuration. He also emphasized the friendly nature of the coding community and encouraged contributions to the project.

Best known as the default cluster DNS of Kubernetes in cloud native ecosystem, CoreDNS is also an extensible and flexible DNS server with a focus on service discovery. The extensibility of CoreDNS comes from its unique plugin-based architecture that allows additions of new features with ease. The flexibility of CoreDNS, on the other hand, comes from 1) a rich list of integrations in cloud native ecosystem, 2) an easy-to-use Corefile configurations, and 3) the flexibility and scalability of DNS itself. After all, DNS itself is a distributed system that scales the Internet. In this session, we will take a close look at the CoreDNS. We will learn how to use CoreDNS across hybrid and multi-cloud environments, fully integrated with various services by cloud vendors at scale. We will also learn how to write a complete CoreDNS plugin for a service discovery feature in Golang. At the end we will also update the current state and the road map of CoreDNS for the near future.