Название: Learning CoreDNS (Early Release)
Автор: John Belamaric, Cricket Liu
Издательство: O’Reilly Media, Inc.
Год: 2019
Страниц: 353
Язык: английский
Формат: epub, rtf, pdf (conv)
Размер: 10.1 MB

Until recently, learning CoreDNS required reading the code or the skimpy documentation on the website. No longer. With this practical book, developers and operators working with Docker containers will understand how to use this standard DNS server with Kubernetes.

John Belamaric, senior staff software engineer at Google, and Cricket Liu, Chief DNS Architect at Infoblox, show you how to configure CoreDNS using real-world configuration examples for achieving specific purposes. You’ll learn the basics of DNS, including how DNS functions as a location broker in container environments, and how it ties in to Kubernetes.

When using CoreDNS and etcd for service registry and discovery, all of the peristent state (data) is stored in etcd. CoreDNS connects to etcd and reads data as needed based on queries and the contents of its cache (if enabled). It is important to isolate the state into a redundant data store, to avoid losing information when a component fails. Running as a stateless service also makes it much simpler to scale CoreDNS - we can run as many instances behind a load balancer to handle our traffic load.