Helm Deployment

Use the official Couchbase Helm Chart to deploy multiple components, including the Autonomous Operator, Admission Controller, Couchbase clusters, and Sync Gateway.

Helm is a tool that streamlines the installation and management of applications on Kubernetes platforms. The official Couchbase Helm Chart can help you easily set up the Couchbase Autonomous Operator and deploy Couchbase clusters.

This page describes how to use the Couchbase Helm Chart to create various deployments of the Autonomous Operator, Admission Controller, Couchbase clusters, and Sync Gateway.

The Couchbase Helm Chart is primarily intended to make it easy to deploy with the defaults to get a working system in an empty cluster. For more complex scenarios, make sure to refer to the operator documentation as well, particularly the operator architecture and reference architecture.

A particular use case that is complex is upgrading so make sure to cover all the Autonomous Operator upgrade and Couchbase Server upgrade sections.

The recommendation, for more complex scenarios, is to manage the operator directly rather than relying on Helm to do it as the operator provides a lot more direct control and this approach simplifies the upgrade process.

The official Couchbase Helm Chart may only be used with Enterprise Edition products, such as Couchbase Server Enterprise Edition and Sync Gateway Enterprise Edition.

Install Helm

Helm 3.1+ is required when installing the official Couchbase Helm Chart.

Follow Helm’s official steps for installing helm on your particular operating system.

Add the Chart Repository

Before you can start using the Couchbase Helm Chart, you’ll need to add the chart repository to your helm installation:

helm repo add couchbase https://couchbase-partners.github.io/helm-charts/

Finish by updating the repository index:

helm repo update

Install the Couchbase Helm Chart

Use the following commands to install the default Couchbase Helm Chart. The default chart deploys the Autonomous Operator, the Admission Controller, and a Couchbase cluster.

Kubernetes
OpenShift

helm install <my-release> --set cluster.name=<cluster-name> couchbase/couchbase-operator

Create an image pull secret for retrieving images from the Red Hat Container Catalog:

oc create secret docker-registry rh-catalog \
  --docker-server=registry.connect.redhat.com \
  --docker-username=<rhel-username> \
  --docker-password=<rhel-password> \
  --docker-email=<docker-email>

Create a file named openshift_values.yaml with the following custom override values:

couchbaseOperator:
  image:
    repository: registry.connect.redhat.com/couchbase/operator
    tag: 2.3.0
  imagePullSecrets:
  - rh-catalog
admissionController:
  image:
    repository: registry.connect.redhat.com/couchbase/admission-controller
    tag: 2.3.0
  imagePullSecrets:
  - rh-catalog
cluster:
   image: registry.connect.redhat.com/couchbase/server:7.0.3-1

Install the chart using the custom override values:

helm install <my-release> -f openshift_values.yaml couchbase/couchbase-operator

Installing the default chart provides a quick way to try out using the Autonomous Operator for managing Couchbase Server on Kubernetes platforms. However, for more involved development and production use-cases, you will need to customize the installation to better your needs.

Customize the Installation

The Couchbase Helm Chart can be installed as-is for previewing Autonomous Operator functionality. However, customizing the installation with your own configuration will be necessary for production environments.

Customizing the chart installation allows you to do two things:

Specify which components will be deployed
Configure the deployed components

The Couchbase Helm Chart is capable of installing and configuring the Autonomous Operator, Admission Controller, Couchbase cluster, and Sync Gateway. Enabling and configuring each component is accomplished by overriding the default values in the Couchbase Helm Chart’s values.yaml file.

There are two methods for specifying overrides during chart installation: --values and --set.

--values
--set

The --values option is the preferred method because it allows you to keep your overrides in a YAML file, rather than specifying them all on the command line.

Create a YAML file and add your overrides to it.

Here’s an example called myvalues.yaml:
```
couchbaseOperator:
  imagePullPolicy: Always
```
Specify your overrides file when you install the chart:
```
helm install my-release --values myvalues.yaml couchbase/couchbase-operator
```
The values in your overrides file (myvalues.yaml) will override their counterparts in the chart’s values.yaml file. Any values in values.yaml that weren’t overridden will keep their defaults.

If you only need to make minor customization, you can specify them on the command line by using the --set option. For example:

helm install my-release --set cluster.servers.default.size=5 couchbase/couchbase-operator

This would translate to the following in the values.yaml of the chart:

cluster:
  servers:
    default:
      size: 5

Any values in values.yaml that weren’t overridden will keep their defaults.

As stated above, Helm works by override-only, with the chart providing various defaults. If you want to override a whole key in the chart, or replace it with another key, then you must explicitly disable the default in addition to adding the new one.

For example, a default bucket is created unless you configure one or otherwise set buckets: null in the values file or buckets=null on the command line. Likewise, the default server configuration will always be created unless you set servers.default to null.

For additional information, refer to the Helm documentation on deleting a default key.

Selective Deployment

In many cases you may only want to install a single component, such as a Couchbase cluster, or an instance of Sync Gateway. Specific components may be enabled/disabled by overriding the default values in the install section of the chart:

# Select what to install
install:
  # install the couchbase operator
  couchbaseOperator: true
  # install the admission controller
  admissionController: true
  # install couchbase cluster
  couchbaseCluster: true
  # install sync gateway
  syncGateway: false

For example, if you wanted to have a Helm release that exclusively managed the Autonomous Operator and Admission Controller, then you would override the value for couchbaseCluster with a value of false, leaving only couchbaseOperator: true and admissionController: true, and all others false. Likewise, if you already had the Autonomous Operator and Admission Controller deployed in your environment, and you just wanted to deploy a Couchbase cluster, then you would override the values for couchbaseOperator and admissionController with a value of false, leaving only couchbaseCluster: true, and all others false.

Even though the Couchbase Helm Chart has full configuration parameters for each component, if a component is disabled in the install section, then that component’s configuration parameters are ignored.

Users

By default, when creating a custom user, the corresponding Group resource is automatically created and bound.

users:
  developer:
    # When autobind is 'true' then the user is
    # created and automatically bound to a group named 'developer'.
    autobind: true
    # password to use for user authentication
    # (alternatively use authSecret)
    password: password
    # optional secret to use containing user password
    authSecret:
    # domain of user authentication
    authDomain: local
    # roles attributed to group
    roles:
      - name: bucket_admin
        bucket: default

To manually configure the corresponding Group resource, set users.<name>.autobind to false and specify the groups and rolebindings resources.

Deploying Sync Gateway

Sync Gateway is disabled by default in the Couchbase Helm Chart. To install the chart with Sync Gateway enabled, you will need to customize the installation to include it:

helm install mobile --set install.syncGateway=true couchbase/couchbase-operator

By default, Sync Gateway is only exposed to the internal Kubernetes network with a ClusterIP service. To change the type of service that is used to expose Sync Gateway, you can specify an override for syncGateway.exposeServiceType during installation:

helm install mobile --set install.syncGateway=true --set syncGateway.exposeServiceType=LoadBalancer couchbase/couchbase-operator

For more information about using Sync Gateway with the Autonomous Operator, you can refer to the Sync Gateway Tutorial.

Production Considerations

TLS Encryption

Production deployments should enable TLS to encrypt traffic between the Autonomous Operator and the Couchbase cluster. TLS certificates can be auto-generated, or provided by the user.

Auto-Generated Certificates

Install the chart with tls enabled:

helm install my-release --set tls.generate=true couchbase/couchbase-operator

The Autonomous Operator will create the certificates and then configure them as Kubernetes Secrets for the cluster.

There is an issue (K8S-1900) that may cause a certificate error when using the Helm chart to upgrade the Autonomous Operator:

certificate cannot be verified for zone

This issue is caused by the certificate not having the necessary subject alternative names (SANs) required by the new version of the Autonomous Operator.

To resolve this issue, start by regenerating the Secrets from the new chart version:

helm template my-release --values values.yaml couchbase/couchbase-operator > secrets.yaml

The secrets.yaml file that is created by the command above will now contain the Kubernetes Secret definitions for the cluster. Remove anything else from the file other than the Secrets with the -operator-tls and -server-tls suffixes for your release. Now update the Secrets in Kubernetes with the new ones:

kubectl replace -f secrets.yaml

The Autonomous Operator should now pick up the new certificates and proceed through the upgrade process.

Bring Your Own Certificates

Create a file named tls_values.yaml with the following custom override values for the Couchbase Helm Chart:

cluster:
   tls:
     static:
       operatorSecret: tls-operator-secret
       serverSecert: my-tls-server-secret

Install the chart using the custom override values.

helm install my-release -f tls_values.yaml couchbase/couchbase-operator

Deploying Multiple Chart Instances (Releases)

The example installation commands on this page assume the default namespace is used (these commands don’t specify the -n option). This is important to note because the Couchbase Helm Chart deploys both the Autonomous Operator and the Admission Controller by default, and these components should not be deployed more than once in the same namespace.

The Admission Controller should only be deployed once per Kubernetes cluster as indicated in Selective Deployment and in the operator architecture. To prevent deployment of the Admission Controller by the Couchbase Helm Chart, you can set the install.admissionController=false parameter either in the values file or on the command line:

helm install my-release --set install.admissionController=false couchbase/couchbase-operator

If you install the default Couchbase Helm Chart multiple times in the same namespace, then you’ll end up with multiple instances of the Autonomous Operator and the Admission Controller, which will cause errors in your deployments.

In addition, the example installation commands on this page also specify my-release as the name for the chart release. If you plan to use Helm to install multiple instances (releases) of the Couchbase Helm Chart, you should consider giving each release a unique name to help you more easily identify the resources that are associated with each release.

If you want Helm to generate a name for you, you can run any of the example installation commands on this page using the -g option instead of the name parameter:

helm install -g couchbase/couchbase-operator

Chart Versions

It is not recommended to install different versions of the Couchbase Helm Chart in the same Kubernetes cluster.

The helm install command will always pull the highest version of a chart. To list the versions of the Couchbase Helm Chart that are available for installation, you can use the helm search command:

helm search hub couchbase

NAME                        	                      CHART VERSION	APP VERSION	DESCRIPTION
https://hub.helm.sh/charts/couchbase/couchbase-...	2.1.0        	2.1.0      	A Helm chart to deploy the Couchbase Autonomous...

Here, the CHART VERSION is 2.1.0, and the APP VERSION (the Autonomous Operator version) is 2.1.0.

To install a specific version of the Couchbase Helm Chart chart, include the --version argument during installation:

helm install my-release --version 2.1.0 couchbase/couchbase-operator

If you’re having trouble finding or installing a specific version of a chart, use the helm repo update command to ensure that you have the latest list of charts.