In this tutorial, you'll start a local Kubernetes cluster with Minikube. You will then deploy Consul with the official Helm chart. After deploying Consul, you will learn how to access the agents. You will then deploy two services that use Consul to discover each other.
Security Warning This tutorial is not for production use. By default, the chart will install an insecure configuration of Consul. Refer to the Kubernetes documentation to determine how you can secure Consul on Kubernetes in production. Additionally, it is highly recommended you use a properly secured Kubernetes cluster or make sure that you understand and enable the recommended security features.
First, you'll need to follow the directions for installing Minikube, including VirtualBox or a similar virtualization tool.
You'll also need to install
kubectl with Homebrew.
$ brew install kubernetes-cli
helm with Homebrew.
$ brew install kubernetes-helm
Start Minikube with the optional
--memory flag specifying the equivalent of 4-8GB of memory, so your pods will have plenty of resources to use. Starting Minikube may take several minutes. It will download a 100-300MB of dependencies and container images.
$ minikube start --memory 4096
»Install Consul with the official Helm chart
Tip: You can deploy a complete Consul datacenter using the official Helm chart. You can review the official Helm chart values to learn more about the default settings.
»Download the demo code and Helm chart
First, add the HashiCorp Helm Chart repository:
$ helm repo add hashicorp https://helm.releases.hashicorp.com"hashicorp" has been added to your repositories
»Create a custom values file
The chart comes with reasonable defaults, however, you will override
a few values to help things go more smoothly with
kind and enable
Create a custom values file called
config.yaml with the
following contents. This configuration will:
- Set the prefix used for all resources in the Helm chart to
- Name the Consul datacenter
- Configure the datacenter to run only 1 server
- Configure the server to use the
- Enable the Consul UI and expose it via a
- Enable Consul service mesh features by setting
- Enable Consul service mesh CRDs by setting
$ cat > config.yaml <<EOFglobal: name: consul datacenter: dc1server: replicas: 1 securityContext: runAsNonRoot: false runAsGroup: 0 runAsUser: 0 fsGroup: 0ui: enabled: true service: type: 'NodePort'connectInject: enabled: truecontroller: enabled: trueEOF
»Deploy Consul on Minikube
helm install, providing your custom values file, the
chart, and a name for your Consul installation. It will print a list of all the
resources that were created.
$ helm install -f config.yaml consul hashicorp/consulNAME: hashicorp...TRUNCATED...To learn more about the release if you are using Helm 3, run: $ helm status hashicorp $ helm get all hashicorp
»Access the Consul UI
Verify Consul was deployed properly by accessing the Consul UI. Run
minikube service list to list your services. Find the one with
consul-ui in the name.
$ minikube service list|-------------|-----------------------------|--------------|----------------------------|| NAMESPACE | NAME | TARGET PORT | URL ||-------------|-----------------------------|--------------|----------------------------|| default | consul-connect-injector-svc | No node port || default | consul-controller-webhook | No node port || default | consul-dns | No node port || default | consul-server | No node port || default | consul-ui | http/80 | http://192.168.64.32:30881 || default | kubernetes | No node port || kube-system | kube-dns | No node port ||-------------|-----------------------------|--------------|----------------------------|
minikube service with the
consul-ui service name as the argument. It will open the service in your web browser.
$ minikube service consul-ui
You can now visit the Consul UI with a list of Consul's services, nodes, and other resources. Currently, you should only find the
consul service listed.
»Access Consul with kubectl and the HTTP API
In addition to accessing Consul with the UI, you can manage Consul with the
HTTP API or by directly connecting to the pod with
»Use Kubectl to access the server
To access the Consul server pod you can start a shell session in the pod
$ kubectl exec -it consul-server-0 -- /bin/sh
Your terminal prompt will change to the following, which indicates you have successfully started an interactive terminal session in the server container.
From the container, you are able to navigate the file system and run Consul CLI commands. For example, you can view the Consul version.
$ consul versionConsul v1.9.4Revision 10bb6cb3bProtocol 2 spoken by default, understands 2 to 3 (agent will automatically use protocol >2 when speaking to compatible agents)
You can also view members of the datacenter.
$ consul membersNode Address Status Type Build Protocol DC Segmentconsul-server-0 172.17.0.6:8301 alive server 1.9.4 2 dc1 <all>minikube 172.17.0.5:8301 alive client 1.9.4 2 dc1 <default>
exit and then enter to leave the container session.
»Consul HTTP API
You can use the Consul HTTP API by communicating with the local agent running on the Kubernetes node. Read the documentation to learn more about using the Consul HTTP API with Kubernetes.
»Deploy services with Kubernetes
Now that you have a running Consul service mesh, you can deploy services to it.
»Deploy two services
You will now deploy a two-tier application made of a backend data service that
returns a number (the
counting service), and a frontend
dashboard that pulls
counting service over HTTP and displays the number.
Create a deployment definition, service, and service account for the
$ cat > counting.yaml <<EOFapiVersion: v1kind: ServiceAccountmetadata: name: counting---apiVersion: v1kind: Servicemetadata: name: countingspec: selector: app: counting ports: - port: 9001 targetPort: 9001---apiVersion: apps/v1kind: Deploymentmetadata: labels: app: counting name: countingspec: replicas: 1 selector: matchLabels: app: counting template: metadata: annotations: 'consul.hashicorp.com/connect-inject': 'true' labels: app: counting spec: containers: - name: counting image: hashicorp/counting-service:0.0.2 ports: - containerPort: 9001EOF
Create a deployment definition, service, and service account for
dashboard service named
$ cat > dashboard.yaml <<EOFapiVersion: v1kind: ServiceAccountmetadata: name: dashboard---apiVersion: v1kind: Servicemetadata: name: dashboardspec: selector: app: dashboard ports: - port: 9002 targetPort: 9002---apiVersion: apps/v1kind: Deploymentmetadata: labels: app: dashboard name: dashboardspec: replicas: 1 selector: matchLabels: app: dashboard template: metadata: annotations: 'consul.hashicorp.com/connect-inject': 'true' 'consul.hashicorp.com/connect-service-upstreams': 'counting:9001' labels: app: dashboard spec: containers: - name: dashboard image: hashicorp/dashboard-service:0.0.4 ports: - containerPort: 9002 env: - name: COUNTING_SERVICE_URL value: 'http://localhost:9001'EOF
kubectl to deploy the counting service.
$ kubectl apply -f counting.yamlserviceaccount/counting createdservice/counting createddeployment.apps/counting created
kubectl to deploy the dashboard service.
$ kubectl apply -f dashboard.yamlserviceaccount/dashboard createdservice/dashboard createddeployment.apps/dashboard created
To verify the services were deployed, refresh the Consul UI until you observe
dashboard services are running.
»Visit the dashboard
To visit the dashboard, forward the pod's port where the dashboard
service is running to your local machine on the same port by providing
the pod name (
dashboard), which you specified in the service definition YAML file.
$ kubectl port-forward deploy/dashboard 9002:9002Forwarding from 127.0.0.1:9002 -> 9002Forwarding from [::1]:9002 -> 9002
Visit localhost:9002 in your web browser. It will display
dashboard UI with a number retrieved from the
counting service using
Consul service discovery.
»Secure service communication with intentions
Consul intentions provide you the ability to control which services are allowed
to communicate. Next, you will use intentions to test the communication between
»Create an intention that denies communication
You can use a Consul
CRD to create an intention that prevents the
dashboard service from reaching
Create a file named
deny.yaml that denies communication between the two services.
$ cat > deny.yaml <<EOFapiVersion: consul.hashicorp.com/v1alpha1kind: ServiceIntentionsmetadata: name: dashboard-to-countingspec: destination: name: counting sources: - name: dashboard action: denyEOF
kubectl to apply the intention.
$ kubectl apply -f deny.yamlserviceintentions.consul.hashicorp.com/dashboard-to-counting created
Verify the services are no longer allowed to communicate by returning to the dashboard UI. The service will display a message that the "Counting Service is Unreachable", and the count will display as "-1".
»Allow the application dashboard to communicate with the Counting service
Finally, remove the intention so that the services can communicate again.
$ kubectl delete -f deny.yamlserviceintentions.consul.hashicorp.com "dashboard-to-counting" deleted
Intentions take effect rather quickly. The next time you visit the
you'll notice that it's successfully communicating with the backend
»Extend your knowledge
»Rolling updates to Consul
While running Consul you may want to make configuration and deployment updates.
You can use
helm upgrade to increase the number of agents, enable additional
features, upgrade the Consul version, or change your configuration. For example,
you could add a
connectInject.default setting and set to true. When this setting
is present and set to
true, the injector will inject the Consul service mesh
sidecars into all pods by default. Otherwise, pods must specify the injection annotation
to opt-in to service mesh sidecar injection. If the default is set to true, pods
can still use the same annotation to explicitly opt-out of injection.
You can practice using
helm upgrade by updating your custom values file to enable
sidecar injection by default.
In the text editor of your choice, modify your
config.yaml file so that the
connectInject stanza now includes a
default: true setting.
connectInject: enabled: true default: true
Initiate the upgrade
-f flag that passes in your new values file.
$ helm upgrade consul -f config.yaml hashicorp/consulRelease "consul" has been upgraded. Happy Helming!NAME: consul...TRUNCATED...To learn more about the release, run: $ helm status consul $ helm get all consul
To learn more about Consul service mesh on Kubernetes, review the service mesh tutorials. To learn how to deploy Consul on a Kubernetes cluster, review the production deployment tutorial. To learn how to secure Consul and services for production, read the Secure Consul and Registered Services on Kubernetes tutorial.