This tutorial installs and configures Consul service mesh on an existing Kubernetes cluster.
By the end of this tutorial, you will be able to identify the installation prerequisites, install Consul with the official Helm chart, and deploy an example workload.
»Prerequisites
The following components are required to complete this tutorial:
Access to a Kubernetes cluster. You can deploy a cluster locally using kind or Minikube.
Using Minikube with VirtualBox: Start Minikube with the VirtualBox drivers:
minikube start --driver=virtualboxkubectl v1.22+. You can issue the
versioncommand to verify thatkubectlis installed:One of the following tools should be installed:
Helm v3.5.4+. Issue the
versioncommand to verify thathelmis installed:The Consul K8s command line tool (
consul-k8s). Issue theversioncommand to verify thatconsul-k8sis installed:
»Clone the Demo Configuration and Application
The learn-consul-kubernetes repository contains several resources for helping you understand how to use Consul in your Kubernetes clusters. Clone the repository to download the demo configuration and application:
Change to the /service-mesh/deploy directory, which contain all of the artifacts used in this tutorial.
»Deploy Consul
You can deploy Consul with Helm or with the consul-k8s command line tool.
To deploy Consul service mesh using Helm, you need a copy of the official chart. You can add the official HashiCorp Consul Helm chart repo from the command line using the Helm CLI.
Update your local Helm repositories to ensure you have the latest Consul Helm chart.
Deploy the Consul Helm chart using the values in config.yaml. This deploys the
control plane for the service mesh, which includes a Consul server,
client, controller, and injector in a dedicated consul Kubernetes namespace.
It also installs a demo instance of Prometheus and Grafana for metrics.
Validate the installation by checking for running Consul pods.
»Interact with Consul
To access the Consul UI, set up port forwarding to port 18500.
Then, go to http://localhost:18500 in your browser. Explore the Consul UI by examining the "Nodes" and "Services" tabs.
You can use kubectl exec to get direct access to any container, including
the Consul server. Use this command to check for a list of Consul's
servers and clients. Consul servers configure and control the service mesh,
while clients help with service discovery.
»Deploy a demo application
You can explore Consul service mesh by installing a demo application. The demo application, named HashiCups, includes a set of three services and a PostgreSQL database. It allows you to order a cup of coffee.
Open a new terminal and deploy the demo application to your cluster.
The services use an annotation that allows Consul to automatically inject a proxy for each service. The proxies create a data plane to handle requests between services based on configuration from Consul. You can check for applications with proxies by selecting the label for Consul injection.
»Explore the application
You can now explore the demo application and how it uses Consul service mesh.
Forward the frontend service to port 18080.
The HashiCups UI will be available at http://localhost:18080 in your browser. Refresh the page a few times.
Go to the Consul UI on http://localhost:18500. You'll find the HashiCups services registered to Consul service mesh with proxies.
Select the product-api service. The Topology tab indicates that requests to
the public-api goes to the product-api before accessing the database.
Consul embeds a graph aggregating successful requests and error metrics.
»Next steps
In this tutorial, you configured Consul service mesh on an existing Kubernetes cluster using the official Helm chart. You also deployed an example application to explore the service topology and track requests.
For a detailed explanation of Consul service mesh, review our tutorial explaining its design and features.
Learn more about using Consul on Kubernetes in the following tutorials:
