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 an Apache 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 Apache 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

RBAC parameters

Parameter	Description	Default
serviceAccount.create	Enable the creation of a ServiceAccount for Cassandra pods	true
serviceAccount.name	Name of the created ServiceAccount	Generated using the cassandra.fullname template
serviceAccount.annotations	Annotations for Cassandra Service Account	{} (evaluated as a template)

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

This chart supports TLS between client and server and between nodes, as explained below:

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

In both cases, it is also necessary to create a secret containing the keystore and truststore certificates and their corresponding protection passwords. This secret is to be passed to the chart via the tlsEncryptionSecretName parameter at deployment-time.

Refer to the chart documentation for more information on creating the secret and a TLS deployment example.

Use a custom configuration file

This chart also supports mounting custom configuration file(s) for Apache Cassandra. This is achieved by setting the existingConfiguration parameter with the name of a ConfigMap that includes the custom configuration file(s).

NOTE: This ConfigMap will override other Apache Cassandra configuration variables set in the chart.

Refer to the chart documentation for more information on customizing an Apache Cassandra deployment.

Initialize the database

The Bitnami Apache Cassandra image image supports the use of custom scripts to initialize a fresh instance. This may be done by creating a Kubernetes ConfigMap that includes the necessary sh or cql scripts and passing this ConfigMap to the chart via the initDBConfigMap parameter.

Refer to the chart documentation for more information on customizing an Apache Cassandra deployment.

Set pod affinity

This chart allows you to set custom pod 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.

Persistence

The Bitnami Apache Cassandra image stores the Apache 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.

If you encounter errors when working with persistent volumes, refer to our troubleshooting guide for persistent volumes.

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. There are two approaches to achieve this:

• Use Kubernetes SecurityContexts by setting the podSecurityContext.enabled and containerSecurityContext.enabled to true. This option is enabled by default in the chart. However, this feature does not work in all Kubernetes distributions.
• Use an init container to change the ownership of the volume before mounting it in the final destination. Enable this container by setting the volumePermissions.enabled parameter to true.

Backup and restore

Refer to our detailed tutorial on backing up and restoring Bitnami Apache Cassandra deployments on Kubernetes.

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.

Learn more about this change and related upgrade considerations.

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.