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Start ArangoDB on Kubernetes in 5 minutes

Starting an ArangoDB database (either single server or full blown cluster) on Kubernetes involves a lot of resources.

The servers needs to run in Pods, you need Secrets for authentication, TLS certificates and Services to enable communication with the database.

Use kube-arangodb, the ArangoDB Kubernetes Operator to greatly simplify this process.

In this guide, we will explain what the ArangoDB Kubernetes Operator is, how to install it and how use it to deploy your first ArangoDB database in a Kubernetes cluster.

What is `kube-arangodb`

kube-arangodb is a set of two operators that you deploy in your Kubernetes cluster to (1) manage deployments of the ArangoDB database and (2) provide PersistentVolumes on local storage of your nodes for optimal storage performance.

Note that the operator that provides PersistentVolumes is not needed to run ArangoDB deployments. You can also use PersistentVolumes provided by other controllers.

In this guide we will focus on the ArangoDeployment operator.

Installing `kube-arangodb`

To install kube-arangodb in your Kubernetes cluster, make sure you have access to this cluster and the rights to deploy resources at cluster level.

For now, any recent Kubernetes cluster will do (e.g. minikube).

Then run (replace <version> with the version of the operator that you want to install):

kubectl apply -f https://raw.githubusercontent.com/arangodb/kube-arangodb/<version>/manifests/crd.yaml
kubectl apply -f https://raw.githubusercontent.com/arangodb/kube-arangodb/<version>/manifests/arango-deployment.yaml

The first command installs two CustomResourceDefinitions in your Kubernetes cluster:

ArangoDeployment is the resource used to deploy ArangoDB database.
ArangoLocalStorage is the resource used to provision PersistentVolumes on local storage.

The second command installs a Deployment that runs the operator that controls ArangoDeployment resources.

Deploying your first ArangoDB database

The first database we are going to deploy is a single server database.

Create a file called single-server.yaml with the following content.

apiVersion: "database.arangodb.com/v1alpha"
kind: "ArangoDeployment"
metadata:
  name: "single-server"
spec:
  mode: Single

Now insert this resource in your Kubernetes cluster using:

kubectl apply -f single-server.yaml

The ArangoDeployment operator in kube-arangodb will now inspect the resource you just deployed and start the process to run a single server database.

To inspect the current status of your deployment, run:

kubectl describe ArangoDeployment single-server
# or shorter
kubectl describe arango single-server

To inspect the pods created for this deployment, run:

kubectl get pods --selector=arango_deployment=single-server

The result will look similar to this:

NAME                                 READY     STATUS    RESTARTS   AGE
single-server-sngl-cjtdxrgl-fe06f0   1/1       Running   0          1m

Once the pod reports that it is has a Running status and is ready, your database s available.

Connecting to your database

The single server database you deployed in the previous chapter is now available, but only from within the Kubernetes cluster.

To make the database available outside your Kubernetes cluster (e.g. for browser access) you must deploy an additional Service.

There are several possible types of Service to choose from. We are going to use the NodePort type to expose the database on port 30529 of every node of your Kubernetes cluster.

Create a file called single-server-service.yaml with the following content.

kind: Service
apiVersion: v1
metadata:
  name: single-server-service
spec:
  selector:
    app: arangodb
    arango_deployment: single-server
    role: single
  type: NodePort
  ports:
  - protocol: TCP
    port: 8529
    targetPort: 8529
    nodePort: 30529

Deploy the Service into your Kubernetes cluster using:

kubectl apply -f single-server-service.yaml

Now you can connect your browser to https://<node name>:30529/, where <node name> is the name or IP address of any of the nodes of your Kubernetes cluster.

Your browser will show a warning about an unknown certificate. Accept the certificate for now.

Then login using username root and an empty password.

If you want to delete your single server ArangoDB database, just run:

kubectl delete ArangoDeployment single-server

Deploying a full blown ArangoDB cluster database

The deployment of a full blown cluster is very similar to deploying a single server database. The difference is in the mode field of the ArangoDeployment specification.

Create a file called cluster.yaml with the following content.

apiVersion: "database.arangodb.com/v1alpha"
kind: "ArangoDeployment"
metadata:
  name: "cluster"
spec:
  mode: Cluster

Now insert this resource in your Kubernetes cluster using:

kubectl apply -f cluster.yaml

The same commands used in the single server deployment can be used to inspect your cluster. Just use the correct deployment name (cluster instead of single-server).

Connecting to your cluster requires a different Service since the selector now has to select your cluster deployment and instead of selecting all Pods with role single it will have to select all coordinator pods.

The service looks like this:

kind: Service
apiVersion: v1
metadata:
  name: cluster-service
spec:
  selector:
    app: arangodb
    arango_deployment: cluster
    role: coordinator
  type: NodePort
  ports:
  - protocol: TCP
    port: 8529
    targetPort: 8529
    nodePort: 31529

Note that we have chosen a different node port (31529) for this Service to avoid conflicts with the port used in single-server-service.

Where to go from here

ArangoDB Kubernetes Operator

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