MongoDB
MongoDB is a cross-platform document-oriented database. 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.
TL;DR;
$ helm install stable/mongodb
Introduction
This chart bootstraps a MongoDB deployment on a Kubernetes cluster using the Helm package manager.
Bitnami charts can be used with Kubeapps for deployment and management of Helm Charts in clusters. This chart has been tested to work with NGINX Ingress, cert-manager, fluentd and Prometheus on top of the BKPR.
Prerequisites
- Kubernetes 1.4+ with Beta APIs enabled
- PV provisioner support in the underlying infrastructure
Installing the Chart
To install the chart with the release name my-release:
$ helm install --name my-release stable/mongodb
The command deploys MongoDB on the Kubernetes cluster in the default configuration. The configuration section lists the parameters that can be configured during installation.
Tip
: List all releases using
helm list
Uninstalling the Chart
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.
Configuration
The following table lists the configurable parameters of the MongoDB chart and their default values.
| Parameter | Description | Default |
|---|---|---|
global.imageRegistry |
Global Docker image registry | nil |
global.imagePullSecrets |
Global Docker registry secret names as an array | [] (does not add image pull secrets to deployed pods) |
image.registry |
MongoDB image registry | docker.io |
image.repository |
MongoDB Image name | bitnami/mongodb |
image.tag |
MongoDB Image tag | {TAG_NAME} |
image.pullPolicy |
Image pull policy | IfNotPresent |
image.pullSecrets |
Specify docker-registry secret names as an array | [] (does not add image pull secrets to deployed pods) |
image.debug |
Specify if debug logs should be enabled | false |
nameOverride |
String to partially override mongodb.fullname template with a string (will prepend the release name) | nil |
fullnameOverride |
String to fully override mongodb.fullname template with a string | nil |
volumePermissions.enabled |
Enable init container that changes volume permissions in the data directory (for cases where the default k8s runAsUser and fsUser values do not work) |
false |
volumePermissions.image.registry |
Init container volume-permissions image registry | docker.io |
volumePermissions.image.repository |
Init container volume-permissions image name | bitnami/minideb |
volumePermissions.image.tag |
Init container volume-permissions image tag | latest |
volumePermissions.image.pullPolicy |
Init container volume-permissions image pull policy | Always |
volumePermissions.resources |
Init container resource requests/limit | nil |
clusterDomain |
Default Kubernetes cluster domain | cluster.local |
usePassword |
Enable password authentication | true |
existingSecret |
Existing secret with MongoDB credentials | nil |
mongodbRootPassword |
MongoDB admin password | random alphanumeric string (10) |
mongodbUsername |
MongoDB custom user (mandatory if mongodbDatabase is set) |
nil |
mongodbPassword |
MongoDB custom user password | random alphanumeric string (10) |
mongodbDatabase |
Database to create | nil |
mongodbEnableIPv6 |
Switch to enable/disable IPv6 on MongoDB | false |
mongodbDirectoryPerDB |
Switch to enable/disable DirectoryPerDB on MongoDB | false |
mongodbSystemLogVerbosity |
MongoDB systen log verbosity level | 0 |
mongodbDisableSystemLog |
Whether to disable MongoDB system log or not | false |
mongodbExtraFlags |
MongoDB additional command line flags | [] |
service.annotations |
Kubernetes service annotations | {} |
service.type |
Kubernetes Service type | ClusterIP |
service.clusterIP |
Static clusterIP or None for headless services | nil |
service.nodePort |
Port to bind to for NodePort service type | nil |
service.loadBalancerIP |
Static IP Address to use for LoadBalancer service type | nil |
service.externalIPs |
External IP list to use with ClusterIP service type | [] |
service.loadBalancerSourceRanges |
List of IP ranges allowed access to load balancer (if supported) | [] (does not add IP range restrictions to the service) |
port |
MongoDB service port | 27017 |
replicaSet.enabled |
Switch to enable/disable replica set configuration | false |
replicaSet.name |
Name of the replica set | rs0 |
replicaSet.useHostnames |
Enable DNS hostnames in the replica set config | true |
replicaSet.key |
Key used for authentication in the replica set | random alphanumeric string (10) |
replicaSet.replicas.secondary |
Number of secondary nodes in the replica set | 1 |
replicaSet.replicas.arbiter |
Number of arbiter nodes in the replica set | 1 |
replicaSet.pdb.enabled |
Switch to enable/disable Pod Disruption Budget | true |
replicaSet.pdb.minAvailable.secondary |
PDB (min available) for the MongoDB Secondary nodes | 1 |
replicaSet.pdb.minAvailable.arbiter |
PDB (min available) for the MongoDB Arbiter nodes | 1 |
replicaSet.pdb.maxUnavailable.secondary |
PDB (max unavailable) for the MongoDB Secondary nodes | nil |
replicaSet.pdb.maxUnavailable.arbiter |
PDB (max unavailable) for the MongoDB Arbiter nodes | nil |
podAnnotations |
Annotations to be added to pods | {} |
podLabels |
Additional labels for the pod(s). | {} |
resources |
Pod resources | {} |
priorityClassName |
Pod priority class name | `` |
nodeSelector |
Node labels for pod assignment | {} |
affinity |
Affinity for pod assignment | {} |
tolerations |
Toleration labels for pod assignment | {} |
updateStrategy |
Statefulsets update strategy policy | RollingUpdate |
securityContext.enabled |
Enable security context | true |
securityContext.fsGroup |
Group ID for the container | 1001 |
securityContext.runAsUser |
User ID for the container | 1001 |
schedulerName |
Name of the k8s scheduler (other than default) | nil |
persistence.enabled |
Use a PVC to persist data | true |
persistence.mountPath |
Path to mount the volume at | /bitnami/mongodb |
persistence.subPath |
Subdirectory of the volume to mount at | "" |
persistence.storageClass |
Storage class of backing PVC | nil (uses alpha storage class annotation) |
persistence.accessModes |
Use volume as ReadOnly or ReadWrite | [ReadWriteOnce] |
persistence.size |
Size of data volume | 8Gi |
persistence.annotations |
Persistent Volume annotations | {} |
persistence.existingClaim |
Name of an existing PVC to use (avoids creating one if this is given) | nil |
extraInitContainers |
Additional init containers as a string to be passed to the tpl function |
{} |
livenessProbe.enabled |
Enable/disable the Liveness probe | true |
livenessProbe.initialDelaySeconds |
Delay before liveness probe is initiated | 30 |
livenessProbe.periodSeconds |
How often to perform the probe | 10 |
livenessProbe.timeoutSeconds |
When the probe times out | 5 |
livenessProbe.successThreshold |
Minimum consecutive successes for the probe to be considered successful after having failed. | 1 |
livenessProbe.failureThreshold |
Minimum consecutive failures for the probe to be considered failed after having succeeded. | 6 |
readinessProbe.enabled |
Enable/disable the Readiness probe | true |
readinessProbe.initialDelaySeconds |
Delay before readiness probe is initiated | 5 |
readinessProbe.periodSeconds |
How often to perform the probe | 10 |
readinessProbe.timeoutSeconds |
When the probe times out | 5 |
readinessProbe.failureThreshold |
Minimum consecutive failures for the probe to be considered failed after having succeeded. | 6 |
readinessProbe.successThreshold |
Minimum consecutive successes for the probe to be considered successful after having failed. | 1 |
initConfigMap.name |
Custom config map with init scripts | nil |
configmap |
MongoDB configuration file to be used | nil |
ingress.enabled |
Enable ingress controller resource | false |
ingress.certManager |
Add annotations for cert-manager | false |
ingress.annotations |
Ingress annotations | [] |
ingress.hosts[0].name |
Hostname to your MongoDB installation | mongodb.local |
ingress.hosts[0].path |
Path within the url structure | / |
ingress.tls[0].hosts[0] |
TLS hosts | mongodb.local |
ingress.tls[0].secretName |
TLS Secret (certificates) | mongodb.local-tls |
ingress.secrets[0].name |
TLS Secret Name | nil |
ingress.secrets[0].certificate |
TLS Secret Certificate | nil |
ingress.secrets[0].key |
TLS Secret Key | nil |
metrics.enabled |
Start a side-car prometheus exporter | false |
metrics.image.registry |
MongoDB exporter image registry | docker.io |
metrics.image.repository |
MongoDB exporter image name | bitnami/mongodb-exporter |
metrics.image.tag |
MongoDB exporter image tag | {TAG_NAME} |
metrics.image.pullPolicy |
Image pull policy | Always |
metrics.image.pullSecrets |
Specify docker-registry secret names as an array | [] (does not add image pull secrets to deployed pods) |
metrics.podAnnotations.prometheus.io/scrape |
Additional annotations for Metrics exporter pod | true |
metrics.podAnnotations.prometheus.io/port |
Additional annotations for Metrics exporter pod | "9216" |
metrics.extraArgs |
String with extra arguments for the MongoDB Exporter | `` |
metrics.resources |
Exporter resource requests/limit | {} |
metrics.serviceMonitor.enabled |
Create ServiceMonitor Resource for scraping metrics using PrometheusOperator | false |
metrics.serviceMonitor.namespace |
Optional namespace which Prometheus is running in | nil |
metrics.serviceMonitor.additionalLabels |
Used to pass Labels that are required by the Installed Prometheus Operator | {} |
metrics.serviceMonitor.relabellings |
Specify Metric Relabellings to add to the scrape endpoint | nil |
metrics.serviceMonitor.alerting.rules |
Define individual alerting rules as required | {} |
metrics.serviceMonitor.alerting.additionalLabels |
Used to pass Labels that are required by the Installed Prometheus Operator | {} |
metrics.livenessProbe.enabled |
Enable/disable the Liveness Check of Prometheus metrics exporter | false |
metrics.livenessProbe.initialDelaySeconds |
Initial Delay for Liveness Check of Prometheus metrics exporter | 15 |
metrics.livenessProbe.periodSeconds |
How often to perform Liveness Check of Prometheus metrics exporter | 5 |
metrics.livenessProbe.timeoutSeconds |
Timeout for Liveness Check of Prometheus metrics exporter | 5 |
metrics.livenessProbe.failureThreshold |
Failure Threshold for Liveness Check of Prometheus metrics exporter | 3 |
metrics.livenessProbe.successThreshold |
Success Threshold for Liveness Check of Prometheus metrics exporter | 1 |
metrics.readinessProbe.enabled |
Enable/disable the Readiness Check of Prometheus metrics exporter | false |
metrics.readinessProbe.initialDelaySeconds |
Initial Delay for Readiness Check of Prometheus metrics exporter | 5 |
metrics.readinessProbe.periodSeconds |
How often to perform Readiness Check of Prometheus metrics exporter | 5 |
metrics.readinessProbe.timeoutSeconds |
Timeout for Readiness Check of Prometheus metrics exporter | 1 |
metrics.readinessProbe.failureThreshold |
Failure Threshold for Readiness Check of Prometheus metrics exporter | 3 |
metrics.readinessProbe.successThreshold |
Success Threshold for Readiness Check of Prometheus metrics exporter | 1 |
Specify each parameter using the --set key=value[,key=value] argument to helm install. For example,
$ helm install --name my-release \
--set mongodbRootPassword=secretpassword,mongodbUsername=my-user,mongodbPassword=my-password,mongodbDatabase=my-database \
stable/mongodb
The above command sets the MongoDB root account password to secretpassword. Additionally, it creates a standard database user named my-user, with the password my-password, who has access to a database named my-database.
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/mongodb
Tip
: You can use the default values.yaml
Production configuration
This chart includes a values-production.yaml file where you can find some parameters oriented to production configuration in comparison to the regular values.yaml.
$ helm install --name my-release -f ./values-production.yaml stable/mongodb
- Switch to enable/disable replica set configuration:
- replicaSet.enabled: false
+ replicaSet.enabled: true
- Start a side-car prometheus exporter:
- metrics.enabled: false
+ metrics.enabled: true
- Enable/disable the Liveness Check of Prometheus metrics exporter:
- metrics.livenessProbe.enabled: false
+ metrics.livenessProbe.enabled: true
- Enable/disable the Readiness Check of Prometheus metrics exporter:
- metrics.readinessProbe.enabled: false
+ metrics.readinessProbe.enabled: true
To horizontally scale this chart, run the following command to scale the number of secondary nodes in your MongoDB replica set.
$ kubectl scale statefulset my-release-mongodb-secondary --replicas=3
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.
Replication
You can start the MongoDB chart in replica set mode with the following command:
$ helm install --name my-release stable/mongodb --set replicaSet.enabled=true
Some characteristics of this chart are:
- Each of the participants in the replication has a fixed stateful set so you always know where to find the primary, secondary or arbiter nodes.
- The number of secondary and arbiter nodes can be scaled out independently.
- Easy to move an application from using a standalone MongoDB server to use a replica set.
Initialize a fresh instance
The Bitnami MongoDB image allows you to use your custom scripts to initialize a fresh instance. In order to execute the scripts, they must be located inside the chart folder files/docker-entrypoint-initdb.d so they can be consumed as a ConfigMap.
Also you can create a custom config map and give it via initConfigMap(check options for more details).
The allowed extensions are .sh, and .js.
Persistence
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.
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.
Upgrading
To 7.0.0
From this version, the way of setting the ingress rules has changed. Instead of using ingress.paths and ingress.hosts as separate objects, you should now define the rules as objects inside the ingress.hosts value, for example:
ingress:
hosts:
- name: mongodb.local
path: /
To 6.0.0
From this version, mongodbEnableIPv6 is set to false by default in order to work properly in most k8s clusters, if you want to use IPv6 support, you need to set this variable to true by adding --set mongodbEnableIPv6=true to your helm command.
You can find more information in the bitnami/mongodb image README.
To 5.0.0
When enabling replicaset configuration, backwards compatibility is not guaranteed unless you modify the labels used on the chart's statefulsets.
Use the workaround below to upgrade from versions previous to 5.0.0. The following example assumes that the release name is my-release:
$ kubectl delete statefulset my-release-mongodb-arbiter my-release-mongodb-primary my-release-mongodb-secondary --cascade=false
Configure Ingress
MongoDB can exposed externally using an Ingress controller. To do so, it's necessary to:
- Install the MongoDB chart setting the parameter
ingress.enabled=true. - Create a ConfigMap to map the external port to use and the internal service/port where to redirect the requests (see https://github.com/kubernetes/ingress-nginx/blob/master/docs/user-guide/exposing-tcp-udp-services.md for more information).
For instance, if you installed the MongoDB chart in the default namespace, you can install the stable/nginx-ingress chart setting the "tcp" parameter in the values.yaml used to install the chart as shown below:
...
tcp:
27017: "default/mongodb:27017"