Chapter 7. Node Discovery and Clustering
For most real-world scenarios, we would need to create a cluster of compute nodes with the applications running on top, which are linked together. For example, the WordPress site that we have been building requires web servers and databases connected together.
Clustered infrastructure has a topology where one class of nodes should be able to discover information about the different, or the same, class of servers. For example, the WordPress application servers need to discover information about database servers, and load balancers need to know about the IP address/hostname of each web server that it's serving traffic to. This chapter focuses on what primitives Ansible offers to group together nodes and discover the attributes of interconnected nodes.
In this chapter, we will learn about:
- Discovering information about other nodes in the cluster
- Generating configurations dynamically using the magic variables discovered
- Why and how to enable...