Using Multiple Zones

High availability in a Kubernetes cluster is implemented using various parameters. High availability of master controllers would provision multiple master controllers. High availability of etcd would provision multiple etcd nodes. High availability of public DNS would provision multiple public DNSes. In a cloud-native application, availability of a cluster would depend on the availability of the region or zone in which the nodes are run. AWS provides various high-availability design patterns, such as Multi Region Architecture, Multiple Cloud Providers, DNS Load Balancing Tier, and Multiple Availability Zones. In this chapter we will discuss the Multiple Availability Zones design pattern as implemented by Kubernetes. Amazon AWS availability zones are distinct physical locations with independent power, network and security and insulated from failures in other availability zones. Availability zones within the same region have low latency network connectivity between them.