DigitalOcean Kubernetes Cluster Monitoring Quickstart

About this Repo

This repository contains Kubernetes manifests and setup instructions for a preconfigured DigitalOcean Kubernetes cluster monitoring stack. The stack consists of the following monitoring, scraping, and visualization components:

• Prometheus, deployed into the cluster as a StatefulSet with 2 replicas that use Persistent Volumes with DigitalOcean Block Storage. In addition, a preconfigured set of Prometheus Alerts, Rules, and Jobs will be stored as a ConfigMap.
• Alertmanager, installed as a StatefulSet with 2 replicas.
• Grafana, installed as a StatefulSet with one replica. In addition, a preconfigured set of Dashboards generated by kubernetes-mixin will be stored as a ConfigMap.
• kube-state-metrics, installed as a Deployment with one replica.
• node-exporter, installed as a DaemonSet.

This repo accompanies the How to Set Up a Prometheus, Grafana and Alertmanager Monitoring Stack on DigitalOcean Kubernetes Community tutorial. To learn more about these components, their Kubernetes manifests, and how to configure them, consult the accompanying tutorial.

Deploying the Monitoring Stack

Before you begin, you'll need the following tools installed in your local development environment:

• The kubectl command-line interface installed on your local machine and configured to connect to your cluster. You can read more about installing and configuring kubectl in its official documentation.
• The git version control system installed on your local machine. To learn how to install git on Ubuntu 18.04, consult How To Install Git on Ubuntu 18.04
• The Coreutils base64 tool installed on your local machine. If you're using a Linux machine, this will most likely already be installed. If you're using OS X, you can use openssl base64, which comes installed by default.

To start, clone this repo on your local machine:

git clone git@github.com:do-community/doks-monitoring.git

Next, move into the cloned repository:

cd doks-monitoring

Set the APP_INSTANCE_NAME and NAMESPACE environment variables, which will be used to configure a unique name for the stack's components and configure the Namespace into which the stack will be deployed:

export APP_INSTANCE_NAME=sammy-cluster-monitoring
export NAMESPACE=default

Use the base64 command to base64-encode a secure Grafana password of your choosing:

export GRAFANA_GENERATED_PASSWORD="$(echo -n 'your_grafana_password' | base64)"

If you're using OS X, you can use the openssl base64 command which comes installed by default.

If you'd like to deploy the stack into a Namespace other thandefault, run the following command to create a new Namespace:

kubectl create namespace "$NAMESPACE"

Now, use awk and envsubst to fill in the APP_INSTANCE_NAME, NAMESPACE, and GRAFANA_GENERATED_PASSWORD variables in the repo's manifest files. After substituting in the variable values, the files will be combined into a master manifest file called $APP_INSTANCE_NAME_manifest.yaml.

awk 'FNR==1 {print "---"}{print}' manifest/* \
 | envsubst '$APP_INSTANCE_NAME $NAMESPACE $GRAFANA_GENERATED_PASSWORD' \
 > "${APP_INSTANCE_NAME}_manifest.yaml"

Now, use kubectl apply -f to apply the manifest and create the stack in the Namespace you configured:

kubectl apply -f "${APP_INSTANCE_NAME}_manifest.yaml" --namespace "${NAMESPACE}"

You can use kubectl get all to monitor deployment status.

Viewing the Grafana Dashboards

Once the stack is up and running, you can access Grafana by either patching the Grafana ClusterIP Service to create a DigitalOcean Load Balancer, or by forwarding a local port.

Exposing the Grafana Service using a Load Balancer

To create a LoadBalancer Service for Grafana, use kubectl patch to update the existing Grafana Service in-place:

kubectl patch svc "$APP_INSTANCE_NAME-grafana" \
  --namespace "$NAMESPACE" \
  -p '{"spec": {"type": "LoadBalancer"}}'

Once the DigitalOcean Load Balancer has been created and assigned an external IP address, you can fetch this external IP using the following commands:

SERVICE_IP=$(kubectl get svc $APP_INSTANCE_NAME-grafana \
  --namespace $NAMESPACE \
  --output jsonpath='{.status.loadBalancer.ingress[0].ip}')
echo "http://${SERVICE_IP}/"

Forwarding a Local Port to Access the Grafana Service

If you don't want to expose the Grafana Service externally, you can also forward local port 3000 into the cluster using kubectl port-forward. To learn more about forwarding ports into a Kubernetes cluster, consult Use Port Forwarding to Access Applications in a Cluster.

kubectl port-forward --namespace ${NAMESPACE} ${APP_INSTANCE_NAME}-grafana-0 3000

You can now access the Grafana UI locally at http://localhost:3000/.

At this point, you should be able to access the Grafana UI. To log in, use the default username admin (if you haven't modified the admin-user parameter), and password you configured above.

Attribution

The manifests in this repo are heavily based on and modified from Google Cloud Platform's click-to-deploy Prometheus solution. A manifest of modifications (changes.md) is included in this repo.