K8ssandra release notes

Release notes for the open-source K8ssandra community project.

K8ssandra provides a production-ready platform for running Apache Cassandra® on Kubernetes. This includes automation for operational tasks such as repairs, backup and restores, and monitoring. Also deployed is Stargate, an open source data gateway that lets you interact programmatically with your Kubernetes-hosted Cassandra resources via a well-defined API.

Latest release: K8ssandra 1.4.0

Release date: 19-November-2021


  • A Kubernetes environment from v1.17 (minimum supported) up to v1.22 (current tested upper bound) - local or via a supported cloud provider
  • Helm v3. Note that K8ssandra 1.4.0 has been tested with Helm v3.5.3. Recommendation: specifically avoid Helm 3.6.0 and 3.6.1 due to a known CVE and subsequent regression. Our testing will resume with Helm v3.6.2 and later. Related: see GH issue 1103.

Supported Kubernetes environments

K8ssandra deployed components

The K8ssandra helm chart deploys the following components. Some are optional, and depending on the configuration, may not be deployed:

  • Apache Cassandra - the deployed version depends on the configured cassandra.version setting:
    • 4.0.1 (default)
    • 3.11.11
    • 3.11.10
    • 3.11.9
    • 3.11.8
    • 3.11.7
  • cass-operator) 1.9.0.
  • Management API for Apache Cassandra (MAAC) 0.1.27
  • Stargate 1.0.40
  • Metric Collector for Apache Cassandra (MCAC) 0.2.0
  • kube-prometheus-stack 12.11.3 chart
  • Medusa for Apache Cassandra 0.11.0
  • medusa-operator 0.3.3
  • Reaper for Apache Cassandra 2.2.5
  • reaper-operator 2.3.0

Upgrade notices

Upgrading from K8ssandra 1.0.0 to 1.4.0

Upgrading directly from K8ssandra 1.0.0 to 1.4.0 causes a StatefulSet update, due to issues #533 and #613). A StatefulSet update has the effect of a rolling restart. Because of issue #411, this could require you to perform a manual restart of all Stargate nodes after the Cassandra cluster is back online. This behavior also impacts in-place restore operations of Medusa backups - see issue #611.

To manually restart Stargate nodes:

  1. Get the Deployment object in your Kubernetes environment:
    kubectl get deployment | grep stargate
  2. Scale down with this command:
    kubectl scale deployment <stargate-deployment> --replicas 0
  3. Run this next command and wait until it reports 0/0 ready replicas. This should happen within a couple seconds.
    kubectl get deployment <stargate-deployment>
  4. Now scale up with:
     kubectl scale deployment <stargate-deployment> --replicas 1

K8ssandra 1.4.0 revisions

Release date: 19-November-2021

The following sections summarize and link to key revisions in K8ssandra 1.4.0. For the latest, refer to the CHANGELOG.


  • Update to Reaper 3.0.0.
  • Update to Medusa 0.11.3.
  • Update to medusa-operator 0.4.0.
  • Update to Managment API v0.1.33.
  • Update to Stargate 1.0.40 #1118.
  • Update to cass-operator v1.9.0 #1194.
  • Update to kube-prometheus-stack v20.0.1 with Prometheus 2.28.1 and Grafana 7.5.1.


  • Make JAVA_OPTS configurable for Stargate #1179.
  • Apply customizable filters on table level metrics in Metric Collector for Apache Cassandra (MCAC).
  • Implement securityContext defaults for operators and security foundations #1140.
  • Bring reaper resources and CRDs up-to-date with main reaper-operator repo; operator-sdk 1.6.1/controller-runtime 0.9.2.#1150.
  • Update CRD versions to v1 from v1beta1 allowing compatibility with Kubernetes 1.22 #1150.
  • Provide several enhancements with #1083. Added support for full query logging, audit logging, and client backpressure (Cassandra 4.0.0 features). Also support for deployment of Cassandra 4.0.1.
  • Make root file system in Cassandra pod read only; security context for containers. #959.
  • Expose cass-operator AdditionalServiceConfig in K8ssandra helm chart’s values.yaml #874.

Bug fixes

  • Update k8ssandra-operator chart #1181.
  • Cass Operator kills C* pods with due to incorrect memory #1129.
  • Azure backups are broken due to missing azure-cli deps #1066.
  • reaper-operator’s role.yaml has more data than it should, causing role name conflicts #1012.
  • Reaper image registry typo and JVM typo fixed #1018.
  • Do not change num_tokens when upgrading #1029.
  • Ensure Cassandra 4x is compatible with Stargate deployments by including allow_alter_rf_during_range_movement in config.

K8ssandra 1.3.1 revisions

Release date: 27-August-2021

The following sections summarize and link to key revisions in K8ssandra 1.3.1. For the latest, refer to the CHANGELOG.


  • Add support for Apache Cassandra 3.11.11 #1063.

Bug fixes

  • Correct Reaper image registry and JVM typos #1018.
  • Correct duplicate roles and rolebindings in reaper-operator 1012.
  • Preserve num_tokens when upgrading to prevent failures when upgrading to 4.0.0 1029.

K8ssandra 1.3.0 revisions

Release date: 27-July-2021

The following sections summarize and link to key revisions in K8ssandra 1.3.0. For the latest, refer to the CHANGELOG.


  • Support for the General Availability (GA) official release of Apache Cassandra 4.0.0.
  • Upgrade to reaper-operator 0.3.3 and Reaper 2.3.0.
  • Upgrade from Stargate 1.0.18 to 1.0.29.
  • Upgrade from Medusa 0.10.1 to 0.11.0.
  • Upgrade from Reaper 2.2.2 to 2.2.5.
  • Integrate Fossa component/license scanning, #812.
  • Upgrade medusa-operator to v0.3.3, #905.

New features

  • Upgrade the Management API from 0.1.26 to 0.1.27 to provide support for Cassandra 4.0.0 (GA), and make Cassandra 4.0.0 the default release, #949.
  • Make affinity configurable for Stargate, #617.
  • Make affinity configurable for Reaper, #847.
  • Experimental support for custom init containers, #952.


  • Allow configuring the namespace of service monitors, #844.
  • Detect IEC formatted c* heap.size and heap.newGenSize; return error identifying issue, #29. Also see: Add validation check for Cassandra heap size properties, #701.
  • Add support for private registries, #420.
  • Add support for Medusa backups on Azure, #685.

Bug fixes

  • Fix property name in scaling docs, #853.
  • Hot replace disallowed characters in generated secret names, #870.
  • Stargate metrics don’t show up in the dashboards, #412.

Doc updates

K8ssandra 1.2.0 revisions

Release date: 02-June-2021

The following sections briefly summarize and link to key developments in K8ssandra 1.2.0. For the latest list, refer to the CHANGELOG.


  • Upgrade to Cassandra 4.0-rc1 #726.

New features

  • Make tolerations configurable #673, #698.


  • Add the ability to attach additional Persistent Volumes (PVs) for Medusa backups #560.
  • Reduce initial delay of Stargate readiness probe #654.
  • Update cass-operator to v1.7.0 #693.
  • Make allocate_tokens_for_replication_factor configurable #741.

Bug fixes

  • Token allocations are random when using 4.0 and lead to collisions #732. Related enhancement: Make allocate_tokens_for_replication_factor configurable #741.
  • Upgrade to Medusa 0.10.1 fixing failed backups after a restore #678.

Doc updates

  • Reference topics for the K8ssandra deployed Helm charts have been updated with the latest descriptions.

K8ssandra 1.1.0 revisions

Each of the following sections present a subset of key developments in K8ssandra 1.1.0. For the complete list, see the CHANGELOG.


  • Shut down cluster by default with in-place restores of Medusa backups #611.
  • Update Management API image locations #637.


  • Add option to disable Cassandra logging sidecar #576.
  • Developer documentation #239.
  • Add support for additionalSeeds in the CassandraDatacenter #547.

Bug fixes

  • Scale up fails if a restore was performed in the past #616.

Doc updates


​ Your feedback and contributions are welcome! To contribute, fork the K8ssandra repo and submit Pull Requests (PRs) for review.

To submit documentation comments or edits, see Contribution guidelines.

Next steps

Read the K8ssandra FAQs - for starters, how to pronounce “K8ssandra.”

If you’re impatient, jump right in with the K8ssandra install steps for these platforms:

  • Local
  • Amazon Elastic Kubernetes Service (EKS)
  • DigitalOcean Kubernetes (DOKS)
  • Google Kubernetes Engine (GKE)
  • Microsoft Azure Kubernetes Service (AKS)

Last modified November 19, 2021: Update RNs for K8ssandra 1.4.0 (#1188) (a2cf298)