Let's simulate a web application by setting up a simple web server whose logs we want to stream into some searchable application. In this case, we'll be using a Kibana UI to perform ad hoc queries against Elasticsearch.
For this example, I'll start three servers in Amazon's Elastic Compute Cluster (EC2), as shown in this diagram:
Each server has a public IP (starting with 54) and a private IP (starting with 172). For interserver communication, I'll be using the private IPs in my configurations. My personal interaction with the web server (to simulate traffic) and with Kibana and Elasticsearch will require the public IPs, since I'm sitting in my house and not in Amazon's data centers.
Note
Pay careful attention to the IP addresses in the shell prompts, as we will be jumping from machine to machine, and I don't want you to get lost. For instance, on the Collector box, the prompt will contain its private IP:
[ec2-user@ip-172-31-26-205 ~]$
If you try this out yourself...