Update notes

This section describes the specific actions you as a Cloud Operator need to complete to accurately plan and successfully perform your Mirantis OpenStack for Kubernetes (MOSK) cluster update to the version 24.2. Consider this information as a supplement to the generic update procedure published in Operations Guide: Update a MOSK cluster.

Cluster update scheme

Starting from MOSK 24.1.5, Mirantis introduces a new update scheme allowing for the update path flexibility.

If you started receiving the patches of the MOSK 24.1 series, there are two ways to update to the MOSK 24.2 series:

  • 24.1.5 (released on June 18, 2024) to 24.2

  • 24.1.7 (upcoming) to 24.2.1

For details, refer to Cluster update scheme.

For those clusters that update between only major versions, the update scheme remains unchaged.


The MOSK cluster will obtain the newly implemented capabilities automatically with no significant impact on the update procedure.

Update impact and maintenance windows planning

The following table provides details on the update impact on a MOSK cluster.

Impact during update to MOSK 24.2

Updated component

Impact on cloud users

Impact on cloud workloads

OpenStack and Tungsten Fabric

  • ~1% of read operations on cloud API resources may fail

  • ~8% of create and update operations on cloud API resources may fail

Open vSwitch networking - interruption of the North-South connectivity, depending on the type of virtual routers used by a workload:

  • Distributed (DVR) routers - no interruption

  • Non-distributed routers, High Availability (HA) mode - interruption up to 1 minute, usually less than 5 seconds

  • Non-distributed routers, non-HA mode - interruption up to 10 minutes

Tungsten Fabric networking - no impact


~1% of read operations on object storage API may fail

IO performance degradation for Ceph-backed virtual storage devices

Host OS components

No impact

Instance network connectivity interruption up to 5 minutes

Host OS kernel

No impact

Restart of instances due to the hypervisor reboot 0


Host operating system needs to be rebooted for the kernel update to be applied. Configure live-migration of workloads to avoid the impact on the instances running on a host.

To properly plan the update maintenance window, use the following documentation:

Known issues during the update

Before updating the cluster, be sure to review the potential issues that may arise during the process and the recommended solutions to address them, as outlined in Known issues.

Pre-update actions

Verify that OpenStackDeploymentSecret is not in use

The OpenStackDeploymentSecret custom resource has been removed in MOSK 24.2. Therefore, verify that sensitive information has been removed from cluster configuration as described in MOSK 23.1 update notes: Remove sensitive information from cluster configuration.

Back up the Cassandra database

MOSK 24.2 includes the updated patch version of the Cassandra database. With the cluster update, Cassandra is updated from 3.11.10 to 3.11.17.

Additionally, the connectivity method between the Tungsten Fabric services and Cassandra database clusters changes from Thrift to Cassandra Query Language (CQL) protocol.

Therefore, Mirantis highly recommends backing up your Cassandra database before updating a MOSK cluster with Tungsten Fabric to 24.2. For the procedure, refer to Back up TF databases.

Post-update actions

Convert v1alpha1 TFOperator custom resource to v2

In MOSK 24.2, the Tungsten Fabric API v2 becomes default for new deployments and includes the ability to convert existing v1alpha1 TFOperator to v2.

Conversion of TFOperator causes recreation of the Tungsten Fabric service pods. Therefore, Mirantis recommends performing the conversion within a maintenance window during or after the update. The conversion is optional in MOSK 24.2.

For the detailed procedure, refer to Convert v1alpha1 TFOperator custom resource to v2.

Disable Tungsten Fabric analytics services

If your cluster runs Tungsten Fabric analytics services and you want to obtain a more lightweight setup, you can disable these services through the custom resource of the Tungsten Fabric Operator. For the details, refer to the Tungsten Fabric analytics services deprecation notice.

Upgrade OpenStack to Antelope

With 24.1, MOSK is rolling out OpenStack Antelope support for both Open vSwitch and Tungsten Fabric-based deployments.

Mirantis encourages you to upgrade to Antelope to start benefitting from the enhanced functionality and new features of this OpenStack release. MOSK allows for direct upgrade from Yoga to Antelope, without the need to upgrade to the intermediate Zed release. To upgrade the cloud, complete the Upgrade OpenStack procedure.