Book Image

Simplifying Service Management with Consul

By : Robert E. Jackson
Book Image

Simplifying Service Management with Consul

By: Robert E. Jackson

Overview of this book

Within the elastic and dynamic nature of cloud computing, efficient and accurate service discovery provides the cornerstone for all communications. HashiCorp Consul facilitates this service discovery efficiently and securely, independent of the operating environment. This book will help you build a solid understanding of both the concepts and applications of HashiCorp Consul. You'll begin by finding out what you can do with Consul, focusing on the conceptual views of configuration samples along with Terraform code to expedite lab environment and hands-on experimentation, which will enable you to apply Consul effectively in your everyday lives. As you advance, you'll learn how to set up your own Consul cluster and agents in a single datacenter or location and understand how Consul utilizes RAFT and GOSSIP protocols for communication. You'll also explore the practical applications of primary Consul use cases, including communication flows and configuration and code examples. With that knowledge, you'll extend Consul across datacenters to discuss the applicability of multiple regions, multiple clouds, and hybrid cloud environments. By the end of this Consul book, you will have the tools needed to create and operate your own Consul cluster and be able to facilitate your service discovery and communication.
Table of Contents (12 chapters)
1
Section 1: Consul Use Cases and Architecture
6
Section 2: Use Cases Deep Dive

Gossiping serfs

Now that we understand a bit more about how a server peer set is established and operates, let's take a deeper look into what everybody is gossiping about. Again, if we start unpacking where the gossip protocol comes from, it utilizes the Serf (https://www.serf.io/) library, which is based on the Scalable Weakly-consistent Infection-style Process Group Membership protocol, which has thankfully been shortened to SWIM (http://www.cs.cornell.edu/info/projects/spinglass/public_pdfs/swim.pdf). We've jumped off of the Raft, and we've gone swimming!

Have a look at the following diagram:

Figure 2.16 – Gossip connections

All of the members of the Consul cluster, the servers and clients, are swimming in the same pool. This enables the distributed discovery of all members of the pool, their status, and—of course—the status of any services registered with the Consul clients. Although gossip is how all of the agents...