bitnamicharts/opensearch repository overview

⁠Bitnami Secure Images Helm chart for OpenSearch

OpenSearch is a scalable open-source solution for search, analytics, and observability. Features full-text queries, natural language processing, custom dictionaries, amongst others.

Overview of OpenSearch⁠

Trademarks: This software listing is packaged by Bitnami. The respective trademarks mentioned in the offering are owned by the respective companies, and use of them does not imply any affiliation or endorsement.

⁠ TL;DR

helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/opensearch

⁠ Introduction

This chart bootstraps an OpenSearch⁠ deployment on a Kubernetes⁠ cluster using the Helm⁠ package manager.

⁠ Before you begin

• Kubernetes 1.23+
• Helm 3.8.0+
• PV provisioner support in the underlying infrastructure

⁠ Installing the chart

To install the chart with the release name my-release:

helm install my-release oci://REGISTRY_NAME/REPOSITORY_NAME/opensearch

These commands deploy OpenSearch on the Kubernetes cluster in the default configuration. The Parameters⁠ section lists the parameters that can be configured during installation.

⁠ Configuration and installation details

This section describes resource settings, rolling tags, credentials, metrics, Gateway API, TLS, init scripts, sidecars, and other options.

⁠ Resource requests and limits

Bitnami charts allow setting resource requests and limits for all containers inside the chart deployment. These are inside the resources value (check parameter table). Setting requests is essential for production workloads and these should be adapted to your specific use case.

To make this process easier, the chart contains the resourcesPreset values, which automatically sets the resources section according to different presets. Check these presets in the bitnami/common chart⁠. However, in production workloads using resourcesPreset is discouraged as it may not fully adapt to your specific needs. Find more information on container resource management in the official Kubernetes documentation⁠.

⁠ Rolling vs immutable tags⁠

It is strongly recommended to use immutable tags in a production environment. This ensures your deployment does not change automatically if the same tag is updated with a different image.

Bitnami will release a new chart updating its containers if a new version of the main container, significant changes, or critical vulnerabilities exist.

⁠ Update credentials

Bitnami charts configure credentials at first boot. Any further change in the secrets or credentials require manual intervention. Follow these instructions:

• Update the user password following the upstream documentation⁠
• Update the password secret with the new values (replace the SECRET_NAME PASSWORD, DASHBOARDS_PASSWORD, LOGSTASH_PASSWORD placeholders)

kubectl create secret generic SECRET_NAME --from-literal=opensearch-password=PASSWORD --from-literal=opensearch-dashboards-password=DASHBOARDS_PASSWORD --from-literal=logstash-password=LOGSTASH_PASSWORD --dry-run -o yaml | kubectl apply -f -

⁠ Prometheus metrics

This chart can be integrated with Prometheus by setting *.metrics.enabled (under the data, ingest, master and coordinating sections) to true. This will expose a Prometheus endpoint using the OpenSearch Prometheus plugin⁠. The OpenSearch service will have the necessary annotations to be automatically scraped by Prometheus.

⁠Prometheus requirements

It is necessary to have a working installation of Prometheus or Prometheus Operator for the integration to work. Install the Bitnami Prometheus helm chart⁠ or the Bitnami Kube Prometheus helm chart⁠ to easily have a working Prometheus in your cluster.

⁠Integration with Prometheus Operator

The chart can deploy ServiceMonitor objects for integration with Prometheus Operator installations. To do so, set the value *.metrics.serviceMonitor.enabled=true (under the data, ingest, master and coordinating sections). Ensure that the Prometheus Operator CustomResourceDefinitions are installed in the cluster or it will fail with the following error:

no matches for kind "ServiceMonitor" in version "monitoring.coreos.com/v1"

Install the Bitnami Kube Prometheus helm chart⁠ for having the necessary CRDs and the Prometheus Operator.

⁠ Gateway API

This chart provides support for exposing OpenSearch using the Gateway API⁠ and its HTTPRoute resource. If you have a Gateway controller installed on your cluster, such as APISIX, Contour, Envoy Gateway, NGINX Gateway Fabric or Kong Ingress Controller you can utilize the Gateway controller to serve your application. To enable Gateway API integration, set httpRoute.enabled to true. The Gateway to be used can be customized by setting the httpRoute.parentRefs parameter. By default, it will reference a Gateway named gateway in the same namespace as the release.

You can specify the list of hostnames to be mapped to the deployment using the httpRoute.hostnames parameter. Additionally, you can customize the rules used to route the traffic to the service by modifying the httpRoute.matches and httpRoute.filters parameters or adding new rules using the httpRoute.extraRules parameter.

This chart also supports creating a BackendTLSPolicy to define the SNI the Gateway should use to connect to the OpenSearch backend pods and how the certificate served by these pods should be verified. To do so, set the backendTLSPolicy.enabled parameter to true. Please note it's required to secure traffic using TLS as explained in the Securing traffic using TLS⁠ section to be able to use this feature.

⁠ Securing traffic using TLS

OpenSearch can encrypt communications by setting security.tls.enabled=true. It is possible to configure the application to use PEM certificates or JKS keystores by setting security.tls.usePEMCerts=true. For the TLS secret management, the chart allows two configuration options:

• Provide your own secrets using the *.existingSecret (under the security.tls.admin, security.tls.master, security.tls.data, security.tls.ingest, security.tls.ingest) value. Also set the correct name of the certificate files using the certKey, keyKey values.
• Have the chart auto-generate the certificates using security.tls.autoGenerated=true.

⁠ Change OpenSearch version

To modify the OpenSearch version used in this chart you can specify a valid image tag⁠ using the image.tag parameter. For example, image.tag=X.Y.Z. This approach is also applicable to other images like exporters.

⁠ Default kernel settings

Currently, OpenSearch requires some changes in the kernel of the host machine to work as expected. If those values are not set in the underlying operating system, the OS containers fail to boot with ERROR messages. More information about these requirements can be found here:

• https://opensearch.org/docs/latest/install-and-configure/install-opensearch/index/#important-settings⁠

This chart uses a privileged initContainer to change those settings in the Kernel by running: sysctl -w vm.max_map_count=262144 && sysctl -w fs.file-max=65536. You can disable the initContainer using the sysctlImage.enabled=false parameter.

⁠ Adding extra environment variables

In case you want to add extra environment variables (useful for advanced operations like custom init scripts), you can use the extraEnvVars property.

extraEnvVars:
  - name: OPENSEARCH_VERSION
    value: 7.0

Alternatively, you can use a ConfigMap or a Secret with the environment variables. To do so, use the extraEnvVarsCM or the extraEnvVarsSecret values.

⁠ Using custom init scripts

For advanced operations, the Bitnami OpenSearch charts allows using custom init scripts that will be mounted inside /docker-entrypoint.init-db. You can include the file directly in your values.yaml with initScripts, or use a ConfigMap or a Secret (in case of sensitive data) for mounting these extra scripts. In this case you use the initScriptsCM and initScriptsSecret values.

initScriptsCM=special-scripts
initScriptsSecret=special-scripts-sensitive

⁠ Snapshot and restore operations

As it's described in the official documentation⁠, it's necessary to register a snapshot repository before you can perform snapshot and restore operations.

This chart allows you to configure snapshot repositories and snapshot policies in OpenSearch. A minimal configuration example looks like this:

snapshots:
  enabled: true
  persistence:
    enabled: true
snapshotRepoPath: "/snapshots"

For details, please refer to the snapshots.* documentation below.

⁠ Sidecars and Init Containers

If you have a need for additional containers to run within the same pod as OpenSearch components (e.g. an additional metrics or logging exporter), you can do so using the XXX.sidecars parameter(s), where XXX is placeholder you need to replace with the actual component(s). Simply define your container according to the Kubernetes container spec.

sidecars:
  - name: your-image-name
    image: your-image
    imagePullPolicy: Always
    ports:
      - name: portname
        containerPort: 1234

Similarly, you can add extra init containers using the initContainers parameter.

initContainers:
  - name: your-image-name
    image: your-image
    imagePullPolicy: Always
    ports:
      - name: portname

⁠ Set pod affinity

This chart allows you to set your custom affinity using the XXX.affinity parameter(s). Find more information about pod affinity in the Kubernetes documentation⁠.

As an alternative, you can use the preset configurations for pod affinity, pod anti-affinity, and node affinity available at the bitnami/common⁠ chart. To do so, set the XXX.podAffinityPreset, XXX.podAntiAffinityPreset, or XXX.nodeAffinityPreset parameters.

⁠ Backup and restore

To back up and restore Helm chart deployments on Kubernetes, you need to back up the persistent volumes from the source deployment and attach them to a new deployment using Velero⁠, a Kubernetes backup/restore tool. Find the instructions for using Velero in this guide⁠.

⁠ FIPS parameters

The FIPS parameters only have effect if you are using images from the Bitnami Secure Images catalog⁠.

For more information on this new support, please refer to the FIPS Compliance section⁠.

⁠ Persistence

The Bitnami OpenSearch⁠ image stores the OpenSearch data at the /bitnami/opensearch/data path of the container.

By default, the chart mounts a Persistent Volume⁠ at this location. The volume is created using dynamic volume provisioning. See the Parameters⁠ section to configure the PVC.

⁠ Adjust permissions of persistent volume mountpoint

As the image run as non-root by default, it is necessary to adjust the ownership of the persistent volume so that the container can write data into it.

By default, the chart is configured to use Kubernetes Security Context to automatically change the ownership of the volume. However, this feature does not work in all Kubernetes distributions. As an alternative, this chart supports using an initContainer to change the ownership of the volume before mounting it in the final destination.

You can enable this initContainer by setting volumePermissions.enabled to true.

⁠ Parameters

The following subsections list global, common, and component-specific parameters.

⁠ Global parameters

⁠ Common parameters

⁠ OpenSearch cluster Parameters

Note: the README for this chart is longer than the DockerHub length limit of 25000, so it has been trimmed. The full README can be found at https://techdocs.broadcom.com/us/en/vmware-tanzu/bitnami-secure-images/bitnami-secure-images/services/bsi-app-doc/apps-charts-opensearch-index.html⁠