charts/bitnami/cassandra

cassandra

Apache Cassandra is a free and open-source distributed database management system designed to handle large amounts of data across many commodity servers or datacenters.

TL;DR

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

Introduction

This chart bootstraps a Cassandra 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 Helm chart has been tested on top of Bitnami Kubernetes Production Runtime (BKPR). Deploy BKPR to get automated TLS certificates, logging and monitoring for your applications.

Prerequisites

• Kubernetes 1.12+
• Helm 3.1.0
• PV provisioner support in the underlying infrastructure

Installing the Chart

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

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

These commands deploy one node with Cassandra 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

Uninstalling the Chart

To uninstall/delete the my-release release:

$ helm delete my-release

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

Parameters

The following table lists the configurable parameters of the Cassandra 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)
global.storageClass	Global storage class for dynamic provisioning	nil

Common parameters

Parameter	Description	Default
nameOverride	String to partially override cassandra.fullname	nil
fullnameOverride	String to fully override cassandra.fullname	nil
clusterDomain	Default Kubernetes cluster domain	cluster.local
commonLabels	Labels to add to all deployed objects	nil
commonAnnotations	Annotations to add to all deployed objects	[]
extraDeploy	Array of extra objects to deploy with the release (evaluated as a template)	nil

Cassandra parameters

Parameter	Description	Default
image.registry	Cassandra Image registry	docker.io
image.repository	Cassandra Image name	bitnami/cassandra
image.tag	Cassandra 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
hostAliases	Add deployment host aliases	[]
dbUser.user	Cassandra admin user	cassandra
dbUser.forcePassword	Force the user to provide a non-empty password for dbUser.user	false
dbUser.password	Password for dbUser.user. Randomly generated if empty	(Random generated)
dbUser.existingSecret	Use an existing secret object for dbUser.user password (will ignore dbUser.password)	nil
initDBConfigMap	Configmap for initialization CQL commands (done in the first node). Useful for creating keyspaces at startup	nil (evaluated as a template)
initDBSecret	Secret for initialization CQL commands (done in the first node) that contain sensitive data. Useful for creating keyspaces at startup	nil (evaluated as a template)
tlsEncryptionSecretName	Secret with keystore, keystore password, truststore and truststore password	{}
existingConfiguration	Pointer to a configMap that contains custom Cassandra configuration files. This will override any Cassandra configuration variable set in the chart	nil (evaluated as a template)
cluster.name	Cassandra cluster name	cassandra
cluster.seedCount	Number of seed nodes (note: must be greater or equal than 1 and less or equal to replicaCount)	1
cluster.numTokens	Number of tokens for each node	256
cluster.datacenter	Datacenter name	dc1
cluster.rack	Rack name	rack1
cluster.enableRPC	Enable Thrift RPC endpoint	true
cluster.enableUDF	Enable CASSANDRA_ENABLE_USER_DEFINED_FUNCTIONS	false
cluster.internodeEncryption	Set internode encryption. NOTE: A value different from 'none' requires setting tlsEncryptionSecretName	none
cluster.clientEncryption	Set client-server encryption. NOTE: A value different from 'false' requires setting tlsEncryptionSecretName	false
jvm.extraOpts	Set the value for Java Virtual Machine extra options (JVM_EXTRA_OPTS)	nil
jvm.maxHeapSize	Set Java Virtual Machine maximum heap size (MAX_HEAP_SIZE). Calculated automatically if nil	nil
jvm.newHeapSize	Set Java Virtual Machine new heap size (HEAP_NEWSIZE). Calculated automatically if nil	nil
command	Override default container command (useful when using custom images)	[]
args	Override default container args (useful when using custom images)	[]
extraEnvVars	Extra environment variables to be set on cassandra container	{}
extraEnvVarsCM	Name of existing ConfigMap containing extra env vars	nil
extraEnvVarsSecret	Name of existing Secret containing extra env vars	nil

Statefulset parameters

Parameter	Description	Default
replicaCount	Number of Cassandra replicas	1
updateStrategy	Update strategy type for the statefulset	RollingUpdate
rollingUpdatePartition	Partition update strategy	nil
priorityClassName	Cassandra priorityClassName	nil
podManagementPolicy	StatefulSet pod management policy	OrderedReady
podAnnotations	Additional pod annotations	{}
podLabels	Additional pod labels	{}
podAffinityPreset	Pod affinity preset. Ignored if affinity is set. Allowed values: soft or hard	""
podAntiAffinityPreset	Pod anti-affinity preset. Ignored if affinity is set. Allowed values: soft or hard	soft
nodeAffinityPreset.type	Node affinity preset type. Ignored if affinity is set. Allowed values: soft or hard	""
nodeAffinityPreset.key	Node label key to match Ignored if affinity is set.	""
nodeAffinityPreset.values	Node label values to match. Ignored if affinity is set.	[]
affinity	Affinity for pod assignment	{} (evaluated as a template)
nodeSelector	Node labels for pod assignment	{} (evaluated as a template)
tolerations	Tolerations for pod assignment	[] (evaluated as a template)
topologySpreadConstraints	Topology Spread Constraints for pod assignment	[] (evaluated as a template)
podSecurityContext.enabled	Enable security context for Cassandra pods	true
podSecurityContext.fsGroup	Group ID for the volumes of the pod	1001
containerSecurityContext.enabled	Cassandra Container securityContext	true
containerSecurityContext.runAsUser	User ID for the Cassandra container	1001
resources.limits	The resources limits for Cassandra containers	{}
resources.requests	The requested resources for Cassandra containers	{}
livenessProbe	Liveness probe configuration for Cassandra	Check values.yaml file
readinessProbe	Readiness probe configuration for Cassandra	Check values.yaml file
customLivenessProbe	Override default liveness probe	nil
customReadinessProbe	Override default readiness probe	nil
extraVolumeMounts	Optionally specify extra list of additional volumeMounts for cassandra container	[]
extraVolumes	Optionally specify extra list of additional volumes for cassandra container	[]
initContainers	Add additional init containers to the cassandra pods	{} (evaluated as a template)
sidecars	Add additional sidecar containers to the cassandra pods	{} (evaluated as a template)
pdb.create	Enable/disable a Pod Disruption Budget creation	false
pdb.minAvailable	Minimum number/percentage of pods that should remain scheduled	1
pdb.maxUnavailable	Maximum number/percentage of pods that may be made unavailable	nil
hostNetwork	Use Host-Network for the PODs (if true, also dnsPolicy: ClusterFirstWithHostNet is set)	false
containerPorts.intra	Intra Port on the Host and Container	7000
containerPorts.tls	TLS Port on the Host and Container	7001
containerPorts.jmx	JMX Port on the Host and Container	7199
containerPorts.cql	CQL Port on the Host and Container	9042
containerPorts.thrift	Thrift Port on the Host and Container	9160
metrics.containerPorts.http	HTTP Port on the Host and Container	8080
metrics.containerPorts.jmx	JMX Port on the Host and Container	5555

Exposure parameters

Parameter	Description	Default
service.type	Kubernetes Service type	ClusterIP
service.port	CQL Port for the Kubernetes service	9042
service.thriftPort	Thrift Port for the Kubernetes service	9160
service.metricsPort	Metrics Port for the Kubernetes service	8080
service.nodePorts.cql	Kubernetes CQL node port	""
service.nodePorts.thrift	Kubernetes Thrift node port	""
service.nodePorts.metrics	Kubernetes Metrics node port	""
service.loadBalancerIP	LoadBalancerIP if service type is LoadBalancer	nil
service.annotations	Annotations for the service	{}
networkPolicy.enabled	Enable NetworkPolicy	false
networkPolicy.allowExternal	Don't require client label for connections	true

Persistence parameters

Parameter	Description	Default
persistence.enabled	Enable Cassandra data persistence using PVC	true
persistence.storageClass	PVC Storage Class for Cassandra data volume	nil
persistence.commitStorageClass	PVC Storage Class for Cassandra Commit Log volume	nil
persistence.annotations	Persistent Volume Claim annotations Annotations	{} (evaluated as a template)
persistence.accessMode	PVC Access Mode for Cassandra data volume	[ReadWriteOnce]
persistence.size	PVC Storage Request for Cassandra data volume	8Gi
persistence.commitLogsize	PVC Storage Request for Cassandra commit log volume	nil
persistence.mountPath	The path the data volume will be mounted at	/bitnami/cassandra
persistence.commitLogMountPath	The path the commit log volume will be mounted at	nil

Volume Permissions parameters

Parameter	Description	Default
volumePermissions.enabled	Enable init container that changes the owner and group of the persistent volume(s) mountpoint to runAsUser:fsGroup	false
volumePermissions.image.registry	Init container volume-permissions image registry	docker.io
volumePermissions.image.repository	Init container volume-permissions image name	bitnami/bitnami-shell
volumePermissions.image.tag	Init container volume-permissions image tag	"10"
volumePermissions.image.pullPolicy	Init container volume-permissions image pull policy	Always
volumePermissions.image.pullSecrets	Specify docker-registry secret names as an array	[] (does not add image pull secrets to deployed pods)
volumePermissions.resources.limits	Init container volume-permissions resource limits	{}
volumePermissions.resources.requests	Init container volume-permissions resource requests	{}
volumePermissions.securityContext.*	Other container security context to be included as-is in the container spec	{}
volumePermissions.securityContext.runAsUser	User ID for the init container (when facing issues in OpenShift or uid unknown, try value "auto")	0

Metrics parameters

Parameter	Description	Default
metrics.enabled	Start a side-car prometheus exporter	false
metrics.image.registry	Cassandra exporter Image registry	docker.io
metrics.image.repository	Cassandra exporter Image name	bitnami/cassandra-exporter
metrics.image.tag	Cassandra exporter Image tag	{TAG_NAME}
metrics.image.pullPolicy	Image pull policy	IfNotPresent
metrics.image.pullSecrets	Specify docker-registry secret names as an array	[] (does not add image pull secrets to deployed pods)
metrics.podAnnotations	Additional annotations for Metrics exporter	{prometheus.io/scrape: "true", prometheus.io/port: "8080"}
metrics.resources	Exporter resource requests/limit	{}
metrics.serviceMonitor.enabled	if true, creates a Prometheus Operator ServiceMonitor (also requires metrics.enabled to be true)	false
metrics.serviceMonitor.namespace	Namespace in which Prometheus is running	nil
metrics.serviceMonitor.interval	Interval at which metrics should be scraped.	nil (Prometheus Operator default value)
metrics.serviceMonitor.scrapeTimeout	Timeout after which the scrape is ended	nil (Prometheus Operator default value)
metrics.serviceMonitor.selector	Prometheus instance selector labels	nil

The above parameters map to the env variables defined in bitnami/cassandra. For more information please refer to the bitnami/cassandra image documentation.

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

helm install my-release \
    --set dbUser.user=admin,dbUser.password=password \
    bitnami/cassandra

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

helm install my-release -f values.yaml bitnami/cassandra

Tip

: You can use the default values.yaml

Configuration and installation details

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.

Enable TLS for Cassandra

You can enable TLS between client and server and between nodes. In order to do so, you need to set the following values:

• For internode cluster encryption, set cluster.internodeEncryption to a value different from none. Available values are all, dc or rack.
• For client-server encryption, set cluster.clientEncryption to true.

In addition to this, you must create a secret containing the keystore and truststore certificates and their corresponding protection passwords. Then, set the tlsEncryptionSecretName when deploying the chart.

You can create the secret (named for example cassandra-tls) using --from-file=./keystore, --from-file=./truststore, --from-literal=keystore-password=PUT_YOUR_KEYSTORE_PASSWORD and --from-literal=truststore-password=PUT_YOUR_TRUSTSTORE_PASSWORD options, assuming you have your certificates in your working directory (replace the PUT_YOUR_KEYSTORE_PASSWORD and PUT_YOUR_TRUSTSTORE_PASSWORD placeholders).To deploy Cassandra with TLS you can use those parameters:

cluster.internodeEncryption=all
cluster.clientEncryption=true
tlsEncryptionSecretName=cassandra-tls

Using custom configuration

This helm chart supports mounting your custom configuration file(s) for Cassandra. This is done by setting the existingConfiguration parameter with the name of a configmap (for example, cassandra-configuration) that includes the custom configuration file(s):

existingConfiguration=cassandra-configuration

Note: this will override any other Cassandra configuration variable set in the chart.

Initializing the database

The Bitnami cassandra image allows having initialization scripts mounted in /docker-entrypoint.initdb. This is done in the chart by setting the parameter initDBConfigMap with the name of a configmap (for example, init-db) that includes the necessary sh or cql scripts:

initDBConfigMap=init-db

If the scripts contain sensitive information, you can use the initDBSecret parameter as well (both can be used at the same time).

Setting Pod's affinity

This chart allows you to set your custom affinity using the affinity parameter. 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 podAffinityPreset, podAntiAffinityPreset, or nodeAffinityPreset parameters.

Persistence

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

Persistent Volume Claims are used to keep the data across deployments. This is known to work in GCE, AWS, and minikube. See the Parameters section to configure the PVC or to disable persistence.

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.

Troubleshooting

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

Upgrading

It's necessary to set the dbUser.password parameter 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/cassandra --set dbUser.password=[PASSWORD]

| Note: you need to substitute the placeholder [PASSWORD] with the value obtained in the installation notes.

To 7.0.0

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.
• Move dependency information from the requirements.yaml to the Chart.yaml
• After running helm dependency update, a Chart.lock file is generated containing the same structure used in the previous requirements.lock
• 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/

To 6.0.0

• Several parameters were renamed or disappeared in favor of new ones on this major version:
  • securityContext.* is deprecated in favor of podSecurityContext and containerSecurityContext.
  • Parameters prefixed with statefulset. were renamed removing the prefix. E.g. statefulset.rollingUpdatePartition -> renamed to rollingUpdatePartition.
  • cluster.replicaCount is renamed to replicaCount.
  • cluster.domain is renamed to clusterDomain.
• Chart labels were adapted to follow the Helm charts standard labels.
• This version also 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.

Consequences:

• Backwards compatibility is not guaranteed. To upgrade to 6.0.0, install a new release of the Cassandra chart, and migrate the data from your previous release. To do so, create an snapshot of the database, and restore it on the new database. Check this guide for more information.

To 5.4.0

The minimumAvailable option has been renamed to minAvailable for consistency with other charts. This is not a breaking change as minimumAvailable never worked before because of an error in chart templates.

To 5.0.0

An issue in StatefulSet manifest of the 4.x chart series rendered chart upgrades to be broken. The 5.0.0 series fixes this issue. To upgrade to the 5.x series you need to manually delete the Cassandra StatefulSet before executing the helm upgrade command.

kubectl delete sts -l release=<RELEASE_NAME>
helm upgrade <RELEASE_NAME> ...

To 4.0.0

This release changes uses Bitnami Cassandra container 3.11.4-debian-9-r188, based on Bash.

To 2.0.0

This release make it possible to specify custom initialization scripts in both cql and sh files.

Breaking changes

• startupCQL has been removed. Instead, for initializing the database, see this section.