DNS is one of the core components making Kubernetes run. It’s essential for most services and service discovery. It’s critical, underappreciated and overlooked at the same time. With the recent switch from Kube-DNS to CoreDNS as the main engine for DNS we wanted to take a retrospective look at the improvements and a future look at new possibilities. In this talk I’ll discuss common DNS issues such as UDP packet loss and resulting tail latency issues, compare the performance and reliability of Kube-DNS and CoreDNS, plus spec out and test possible iterative setups with advanced CoreDNS features such as local Daemonset caching, TCP support, prefetching, DNS over GRPC and GRPC based watches.
