stable/rethinkdb/README.md
As of Nov 13, 2020, charts in this repo will no longer be updated. For more information, see the Helm Charts Deprecation and Archive Notice, and Update.
This chart is deprecated and no longer supported.
I have heavily borrowed and extended code (peer discovery and probe) from the following project to build this Helm Chart and Docker image: https://github.com/rosskukulinski/kubernetes-rethinkdb-cluster
This chart implements a dynamically scalable RethinkDB Cluster using Kubernetes StatefulSets.
To install the chart with the release name my-release:
$ helm install --name my-release stable/rethinkdb
The following table lists the configurable parameters of the rethinkdb chart and their default values.
| Parameter | Description | Default |
|---|---|---|
image.name | Custom RethinkDB image name for auto-joining and probe | codylundquist/helm-rethinkdb-cluster |
image.tag | Custom RethinkDB image tag | 0.1.0 |
image.pullPolicy | Custom RethinkDB image pull policy | IfNotPresent |
cluster.replicas | Number of RethinkDB Cluster replicas | 3 |
cluster.resources | Resource configuration for each RethinkDB Cluster Pod | {} |
cluster.podAnnotations | Annotations to be added to RethinkDB Cluster Pods | {} |
cluster.service.annotations | Annotations to be added to RethinkDB Cluster Service | {} |
cluster.storageClass.enabled | If true, create a StorageClass for the cluster. Note: You must set a provisioner | false |
cluster.storageClass.provisioner | Provisioner definition for StorageClass | undefined |
cluster.storageClass.parameters | Parameters for StorageClass | undefined |
cluster.persistentVolume.enabled | If true, persistent volume claims are created | true |
cluster.persistentVolume.storageClass | Persistent volume storage class | default |
cluster.persistentVolume.accessMode | Persistent volume access modes | [ReadWriteOnce] |
cluster.persistentVolume.size | Persistent volume size | 1Gi |
cluster.persistentVolume.annotations | Persistent volume annotations | {} |
cluster.rethinkCacheSize | RethinkDB cache-size value in MB | 100 |
proxy.replicas | Number of RethinkDB Proxy replicas | 1 |
proxy.resources | Resource configuration for each RethinkDB Proxy Pod | {} |
proxy.podAnnotations | Annotations to be added to RethinkDB Proxy Pods | {} |
proxy.service.type | RethinkDB Proxy Service Type | ClusterIP |
proxy.service.annotations | Annotations to be added to RethinkDB Cluster Service | {} |
proxy.service.clusterIP | Internal controller proxy service IP | "" |
proxy.service.externalIPs | Controller service external IP addresses | [] |
proxy.service.loadBalancerIP | IP address to assign to load balancer (if supported) | "" |
proxy.service.loadBalancerSourceRanges | List of IP CIDRs allowed access to load balancer (if supported) | [] |
proxy.driverTLS.enabled | Should RethinkDB Proxy TLS be enabled. Note: If enabled, you must set a key and cert | false |
proxy.driverTLS.key | RSA Private Key | undefined |
proxy.driverTLS.cert | Certificate | undefined |
ports.cluster | RethinkDB Cluster Port | 29015 |
ports.driver | RethinkDB Driver Port | 28015 |
ports.admin | RethinkDB Admin Port | 8080 |
rethinkdbPassword | Password for the RethinkDB Admin user | rethinkdb |
Specify each parameter using the --set key=value[,key=value] argument to helm install.
Alternatively, a YAML file that specifies the values for the parameters can be provided while installing the chart. For example,
$ helm install --name my-release -f values.yaml stable/rethinkdb
Tip: You can use the default values.yaml
The initial admin password is set by the config value rethinkdbPassword. This value is also used by the probe which periodically checks if the RethinkDB Cluster and Proxy are still running. If you change the RethinkDB admin password via a query (i.e. r.db('rethinkdb').table('users').update({password: 'new-password'})) this will cause the probe to fail which then restarts the pods over and over. To stablize the cluster, you also need to use helm upgrade to update the password in the Kubernetes Secrets storage by doing:
$ helm upgrade --set rethinkdbPassword=new-password my-release stable/rethinkdb
The admin port is not available outside of the cluster for security reasons. The only way to access the admin console is to use a Kubernetes Proxy. To open up the admin console:
$ kubectl proxy
Starting to serve on 127.0.0.1:8001
Then use the following URL: http://localhost:8001/api/v1/namespaces/NAMESPACE/services/RELEASE_NAME-rethinkdb-admin/proxy
Make sure a replace NAMEPSPACE with the correct namespace and RELEASE_NAME that was used when installing the chart.
And then open up your browser to http://localhost:8080 and you should see the admin console
Deleting a StatefulSet will not delete associated Persistent Volumes.
Do the following after deleting the chart release to clean up orphaned Persistent Volumes.
$ kubectl delete pvc -l release=my-release
If any RethinkDB server fails it gets re-joined eventually. You can test the scenario by killing process of one of the pods:
$ kubectl get pods -l release=my-release
NAME READY STATUS RESTARTS AGE
my-release-rethinkdb-cluster-0 1/1 Running 0 1m
my-release-rethinkdb-cluster-1 1/1 Running 0 2m
my-release-rethinkdb-cluster-2 1/1 Running 0 2m
my-release-rethinkdb-proxy-2517940628-81dxd 1/1 Running 1 1m
$ kubectl exec -it my-release-rethinkdb-cluster-0 -- ps aux | grep 'rethinkdb'
root 7 0.1 2.1 233496 43408 ? Ssl 16:56 0:00 rethinkdb --ser
root 26 0.0 0.4 146948 8204 ? S 16:56 0:00 rethinkdb --ser
root 100 0.0 0.7 157192 16060 ? S 16:56 0:00 rethinkdb --ser
$ kubectl exec -it my-release-rethinkdb-cluster-0 -- kill 7
Scaling should be managed by helm upgrade, which is the recommended way. Example:
$ helm upgrade --set cluster.replicas=4 my-release stable/rethinkdb