Kubernetes Cookbook - Second Edition

Getting ready

Before we learn a more flexible way to set up an etcd cluster, we should know etcd comes with two major versions so far, which are v2 and v3. etcd3 is a newer version that aims to be more stable, efficient, and reliable. Here is a simple comparison to introduce the major differences in their implementation:

	etcd2	etcd3
Protocol	http	gRPC
Key expiration	TTL mechanism	Leases
Watchers	Long polling over HTTP	Via a bidirectional gRPC stream

etcd3 aims to be the next generation of etcd2 . etcd3 supports the gRPC protocol by default. gRPC uses HTTP2, which allows multiple RPC streams over a TCP connection. In etcd2, however, a HTTP request must establish a connection in every request it makes. ...