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| 1 | +# Start ArangoDB on Kubernetes in 5min |
| 2 | + |
| 3 | +Starting an ArangoDB database (either single server or full blown cluster) |
| 4 | +on Kubernetes involves a lot of resources. |
| 5 | + |
| 6 | +The servers needs to run in `Pods`, you need `Secrets` for authentication, |
| 7 | +TLS certificates and `Services` to enable communication with the database. |
| 8 | + |
| 9 | +Use `kube-arangodb`, the ArangoDB Kubernetes operator to greatly simplify |
| 10 | +this process. |
| 11 | + |
| 12 | +In this guide, we'll explain what the ArangoDB Kubernetes operator is, |
| 13 | +how to install it and how use it to deploy your first ArangoDB database |
| 14 | +in a Kubernetes cluster. |
| 15 | + |
| 16 | +## What is `kube-arangodb` |
| 17 | + |
| 18 | +`kube-arangodb` is a set of two operators that you deploy in your Kubernetes |
| 19 | +cluster to (1) manage deployments of the ArangoDB database and (2) |
| 20 | +provide `PersistenVolumes` on local storage of your nodes for optimal |
| 21 | +storage performace. |
| 22 | + |
| 23 | +Note that the operator that provides `PersistentVolumes` is not needed to |
| 24 | +run ArangoDB deployments. You can also use `PersistentVolumes` provided |
| 25 | +by other controllers. |
| 26 | + |
| 27 | +In this guide we'll focus on the `ArangoDeployment` operator. |
| 28 | + |
| 29 | +## Installing `kube-arangodb` |
| 30 | + |
| 31 | +To install `kube-arangodb` in your Kubernetes cluster, make sure |
| 32 | +you have acces to this cluster and the rights to deploy resources |
| 33 | +at cluster level. |
| 34 | + |
| 35 | +For now, any recent Kubernetes cluster will do (e.g. `minikube`). |
| 36 | + |
| 37 | +Then run (replace `<version>` with the version of the operator that you want to install): |
| 38 | + |
| 39 | +```bash |
| 40 | +kubectl apply -f https://raw.githubusercontent.com/arangodb/kube-arangodb/<version>/manifests/crd.yaml |
| 41 | +kubectl apply -f https://raw.githubusercontent.com/arangodb/kube-arangodb/<version>/manifests/arango-deployment.yaml |
| 42 | +``` |
| 43 | + |
| 44 | +The first command installs two `CustomResourceDefinitions` in your Kubernetes cluster: |
| 45 | + |
| 46 | +- `ArangoDeployment` is the resource used to deploy ArangoDB database. |
| 47 | +- `ArangoLocalStorage` is the resource used to provision `PersistentVolumes` on local storage. |
| 48 | + |
| 49 | +The second command installs a `Deployment` that runs the operator that controls |
| 50 | +`ArangoDeployment` resources. |
| 51 | + |
| 52 | +## Deploying your first ArangoDB database |
| 53 | + |
| 54 | +The first database we're going to deploy is a single server database. |
| 55 | + |
| 56 | +Create a file called `single-server.yaml` with the following content. |
| 57 | + |
| 58 | +```yaml |
| 59 | +apiVersion: "database.arangodb.com/v1alpha" |
| 60 | +kind: "ArangoDeployment" |
| 61 | +metadata: |
| 62 | + name: "single-server" |
| 63 | +spec: |
| 64 | + mode: single |
| 65 | +``` |
| 66 | +
|
| 67 | +Now insert this resource in your Kubernetes cluster using: |
| 68 | +
|
| 69 | +```bash |
| 70 | +kubectl apply -f single-server.yaml |
| 71 | +``` |
| 72 | + |
| 73 | +The `ArangoDeployment` operator in `kube-arangodb` will now inspect the |
| 74 | +resource you just deployed and start the process to run a single server database. |
| 75 | + |
| 76 | +To inspect the currentl status of your deployment, run: |
| 77 | + |
| 78 | +```bash |
| 79 | +kubectl describe ArangoDeployment single-server |
| 80 | +# or shorter |
| 81 | +kubectl describe arango single-server |
| 82 | +``` |
| 83 | + |
| 84 | +To inspect the pods created for this deployment, run: |
| 85 | + |
| 86 | +```bash |
| 87 | +kubectl get pods --selector=arango_deployment=single-server |
| 88 | +``` |
| 89 | + |
| 90 | +The result will look similar to this: |
| 91 | + |
| 92 | +```plain |
| 93 | +NAME READY STATUS RESTARTS AGE |
| 94 | +single-server-sngl-cjtdxrgl-fe06f0 1/1 Running 0 1m |
| 95 | +``` |
| 96 | + |
| 97 | +Once the pod reports that it is has a `Running` status and is ready, |
| 98 | +your database s available. |
| 99 | + |
| 100 | +## Connecting to your database |
| 101 | + |
| 102 | +The single server database you deployed in the previous chapter is now |
| 103 | +available, but only from within the Kubernetes cluster. |
| 104 | + |
| 105 | +To make the database available outside your Kubernetes cluster (e.g. for browser acces) |
| 106 | +you must deploy an additional `Service`. |
| 107 | + |
| 108 | +There are several possible types of `Service` to choose from. |
| 109 | +We're going to use the `NodePort` type to expose the database on port 30529 of |
| 110 | +every node of your Kubernetes cluster. |
| 111 | + |
| 112 | +Create a file called `single-server-service.yaml` with the following content. |
| 113 | + |
| 114 | +```yaml |
| 115 | +kind: Service |
| 116 | +apiVersion: v1 |
| 117 | +metadata: |
| 118 | + name: single-server-service |
| 119 | +spec: |
| 120 | + selector: |
| 121 | + app: arangodb |
| 122 | + arango_deployment: single-server |
| 123 | + role: single |
| 124 | + type: NodePort |
| 125 | + ports: |
| 126 | + - protocol: TCP |
| 127 | + port: 8529 |
| 128 | + targetPort: 8529 |
| 129 | + nodePort: 30529 |
| 130 | +``` |
| 131 | +
|
| 132 | +Deploy the `Service` into your Kubernetes cluster using: |
| 133 | + |
| 134 | +```bash |
| 135 | +kubectl apply -f single-server-service.yaml |
| 136 | +``` |
| 137 | + |
| 138 | +Now you can connect your browser to `https://<node name>:30529/`, |
| 139 | +where `<node name>` is the name or IP address of any of the nodes |
| 140 | +of your Kubernetes cluster. |
| 141 | + |
| 142 | +Your browser will show a warning about an unknown certificate. |
| 143 | +Accept the certificate for now. |
| 144 | + |
| 145 | +Then login using username `root` and an empty password. |
| 146 | + |
| 147 | +If you want to delete your single server ArangoDB database, just run: |
| 148 | + |
| 149 | +```bash |
| 150 | +kubectl delete ArangoDeployment single-server |
| 151 | +``` |
| 152 | + |
| 153 | +## Deploying a full blown ArangoDB cluster database |
| 154 | + |
| 155 | +The deployment of a full blown cluster is very similar to deploying |
| 156 | +a single server database. The difference is in the `mode` field of |
| 157 | +the `ArangoDeployment` specification. |
| 158 | + |
| 159 | +Create a file called `cluster.yaml` with the following content. |
| 160 | + |
| 161 | +```yaml |
| 162 | +apiVersion: "database.arangodb.com/v1alpha" |
| 163 | +kind: "ArangoDeployment" |
| 164 | +metadata: |
| 165 | + name: "cluster" |
| 166 | +spec: |
| 167 | + mode: cluster |
| 168 | +``` |
| 169 | + |
| 170 | +Now insert this resource in your Kubernetes cluster using: |
| 171 | + |
| 172 | +```bash |
| 173 | +kubectl apply -f cluster.yaml |
| 174 | +``` |
| 175 | + |
| 176 | +The same commands used in the single server deployment can be used |
| 177 | +to inspect your cluster. Just use the correct deployment name (`cluster` instead of `single-server`). |
| 178 | + |
| 179 | +Connecting to your cluster requires a different `Service` since the |
| 180 | +selector now has to select your `cluster` deployment and instead |
| 181 | +of selecting all `Pods` with role `single` it will have to select |
| 182 | +all coordinator pods. |
| 183 | + |
| 184 | +The service looks like this: |
| 185 | + |
| 186 | +```yaml |
| 187 | +kind: Service |
| 188 | +apiVersion: v1 |
| 189 | +metadata: |
| 190 | + name: cluster-service |
| 191 | +spec: |
| 192 | + selector: |
| 193 | + app: arangodb |
| 194 | + arango_deployment: cluster |
| 195 | + role: coordinator |
| 196 | + type: NodePort |
| 197 | + ports: |
| 198 | + - protocol: TCP |
| 199 | + port: 8529 |
| 200 | + targetPort: 8529 |
| 201 | + nodePort: 31529 |
| 202 | +``` |
| 203 | + |
| 204 | +Note that we've choosen a different node port (31529) for this `Service` |
| 205 | +to avoid conflicts with the port used in `single-server-service`. |
| 206 | + |
| 207 | +## Where to go from here |
| 208 | + |
| 209 | +- [Reference manual](../../Programs/kube-arangodb/README.md) |
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