MongoDB(R) is an open source NoSQL database that uses JSON for data storage. MongoDB(TM) Sharded improves scalability and reliability for large datasets by distributing data across multiple machines.

Overview of MongoDB® Sharded

Disclaimer: The respective trademarks mentioned in the offering are owned by the respective companies. We do not provide a commercial license for any of these products. This listing has an open-source license. MongoDB(R) is run and maintained by MongoDB, which is a completely separate project from Bitnami.

$ helm repo add bitnami https://charts.bitnami.com/bitnami
$ helm install my-release bitnami/mongodb-sharded

This chart bootstraps a MongoDB(®) Sharded deployment on a Kubernetes cluster using the Helm package manager.

Classified as a NoSQL database, MongoDB® eschews the traditional table-based relational database structure in favor of JSON-like documents with dynamic schemas, making the integration of data in certain types of applications easier and faster.

This chart uses the sharding method for distributing data across multiple machines. This is meant for deployments with very large data sets and high throughput operations.

Bitnami charts can be used with Kubeapps for deployment and management of Helm Charts in clusters.

• Kubernetes 1.19+
• Helm 3.2.0+
• PV provisioner support in the underlying infrastructure
• ReadWriteMany volumes for deployment scaling

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

$ helm install my-release bitnami/mongodb-sharded

The command deploys MongoDB® on the Kubernetes cluster in the default configuration. The Parameters section lists the parameters that can be configured during installation.

Tip: List all releases using helm list

To uninstall/delete the my-release deployment:

$ helm delete my-release

The command removes all the Kubernetes components associated with the chart and deletes the release.

Specify each parameter using the --set key=value[,key=value] argument to helm install. For example,

$ helm install my-release \
  --set shards=4,configsvr.replicaCount=3,shardsvr.dataNode.replicaCount=2 \
    bitnami/mongodb-sharded

The above command sets the number of shards to 4, the number of replicas for the config servers to 3 and number of replicas for data nodes to 2.

Alternatively, a YAML file that specifies the values for the parameters can be provided while installing the chart. For example,

$ helm install my-release -f values.yaml bitnami/mongodb-sharded

Tip: You can use the default values.yaml

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.

To modify the MongoDB® 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.

This chart deploys a sharded cluster by default. Some characteristics of this chart are:

• It allows HA by enabling replication on the shards and the config servers. The mongos instances can be scaled horizontally as well.
• The number of secondary and arbiter nodes can be scaled out independently.

The Bitnami MongoDB® image allows you to use your custom scripts to initialize a fresh instance. You can create a custom config map and give it via initScriptsCM(check options for more details).

The allowed extensions are .sh, and .js.

If you have a need for additional containers to run within the same pod as Kibana (e.g. an additional metrics or logging exporter), you can do so via the sidecars config parameter (available in the mongos, shardsvr.dataNode, shardsvr.arbiter, configsvr and common sections). 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
    containerPort: 1234

In case you want to add extra environment variables (useful for advanced operations like custom init scripts), you can use the extraEnvVars (available in the mongos, shardsvr.dataNode, shardsvr.arbiter, configsvr and common sections) property.

extraEnvVars:
  - name: MONGODB_VERSION
    value: 4.0

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

It is possible to not deploy any shards or a config server. For example, it is possible to simply deploy mongos instances that point to an external MongoDB® sharded database. If that is the case, set the configsvr.external.host and configsvr.external.replicasetName for the mongos instances to connect. For authentication, set the configsvr.external.rootPassword and configsvr.external.replicasetKey values.

The Bitnami MongoDB® image stores the MongoDB® data and configurations at the /bitnami/mongodb path of the container.

The chart mounts a Persistent Volume at this location. The volume is created using dynamic volume provisioning.

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.

The Bitnami Kibana chart supports mounting extra volumes (either PVCs, secrets or configmaps) by using the extraVolumes and extraVolumeMounts properties (available in the mongos, shardsvr.dataNode, shardsvr.arbiter, configsvr and common sections). This can be combined with advanced operations like adding extra init containers and sidecars.

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

As an alternative, you can use of 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.

Find more information about how to deal with common errors related to Bitnami's Helm charts in this troubleshooting guide.

If authentication is enabled, it's necessary to set the auth.rootPassword and auth.replicaSetKey when upgrading for readiness/liveness probes to work properly. When you install this chart for the first time, some notes will be displayed providing the credentials you must use. Please note down the password, and run the command below to upgrade your chart:

$ helm upgrade my-release bitnami/mongodb-sharded --set auth.rootPassword=[PASSWORD] (--set auth.replicaSetKey=[auth.replicaSetKey])

Note: you need to substitute the placeholders [PASSWORD] and [auth.replicaSetKey] with the values obtained in the installation notes.

This major release renames several values in this chart and adds missing features, in order to be inline with the rest of assets in the Bitnami charts repository.

Affected values:

• Authentication parameters are reorganized under the auth.* parameter:
  • usePassword is renamed to auth.enabled.
  • mongodbRootPassword, replicaSetKey, existingSecret and usePasswordFile are now auth.rootPassword, auth.replicaSetKey, auth.existingSecret and auth.usePasswordFile respectively.
• common.containerPorts.mongo is renamed to common.containerPorts.mongodb
• pdb.enabled is renamed to pdb.create
• XXX.replicas is renamed to XXX.replicaCount
• service.port is renamed to service.ports.mongodb
• metrics.containerPort is renamed to metrics.containerPorts.metrics
• service.nodePort is renamed to service.nodePorts.mongodb
• securityContext is splitted into podSecurityContext and containerSecurityContext and moved into the different sections (mongos, shardsvr.dataNode, shardsvr.arbiterand configsvr):
  • securityContext.fsGroup is renamed to XXX.podSecurityContext.fsGroup
  • securityContext.runAsUser is renamed to XXX.containerSecurityContext.runAsUser
  • securityContext.runAsNonRoot is renamed to XXX.containerSecurityContext.runAsNonRoot
• redinessProbe, livenessProbe and startupProbe are moved to the different sections (mongos, shardsvr.dataNode, shardsvr.arbiterand configsvr)

In this version, the mongodb-exporter bundled as part of this Helm chart was updated to a new version which, even it is not a major change, can contain breaking changes (from 0.11.X to 0.30.X). Please visit the release notes from the upstream project at https://github.com/percona/mongodb_exporter/releases

This version introduces bitnami/common, a library chart as a dependency. More documentation about this new utility could be found here. Please, make sure that you have updated the chart dependencies before executing any upgrade.

On November 13, 2020, Helm v2 support was formally finished, this major version is the result of the required changes applied to the Helm Chart to be able to incorporate the different features added in Helm v3 and to be consistent with the Helm project itself regarding the Helm v2 EOL.

What changes were introduced in this major version?

• Previous versions of this Helm Chart use apiVersion: v1 (installable by both Helm 2 and 3), this Helm Chart was updated to apiVersion: v2 (installable by Helm 3 only). Here you can find more information about the apiVersion field.
• The different fields present in the Chart.yaml file has been ordered alphabetically in a homogeneous way for all the Bitnami Helm Charts

Considerations when upgrading to this version

• If you want to upgrade to this version from a previous one installed with Helm v3, you shouldn't face any issues
• If you want to upgrade to this version using Helm v2, this scenario is not supported as this version doesn't support Helm v2 anymore
• If you installed the previous version with Helm v2 and wants to upgrade to this version with Helm v3, please refer to the official Helm documentation about migrating from Helm v2 to v3

Useful links

• https://docs.bitnami.com/tutorials/resolve-helm2-helm3-post-migration-issues/
• https://helm.sh/docs/topics/v2_v3_migration/
• https://helm.sh/blog/migrate-from-helm-v2-to-helm-v3/

MongoDB® container images were updated to 4.4.x and it can affect compatibility with older versions of MongoDB®. Refer to the following guide to upgrade your applications:

• Upgrade a Sharded Cluster to 4.4

Copyright © 2022 Bitnami

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.