New features

OpenStack Victoria LTS

Implemented full support for OpenStack Victoria with OVS or Tungsten Fabric 5.1. However, for new OpenStack Victoria with Tungsten Fabric deployments, Mirantis recommends that you install Tungsten Fabric 2011, which is shipped as TechPreview in this release.

Verified the upgrade path from Ussuri with OVS or Tungsten Fabric 5.1 to Victoria with OVS or Tungsten Fabric 5.1.

OpenStack Ussuri is considered deprecated and will be declared unsupported in one of the upcoming releases. Therefore, start planning your Ussuri to Victoria cloud upgrade.

Default policies override for core OpenStack services

Implemented the mechanism to define additional policy rules for the core OpenStack services through the OpenStackDeployment Custom Resource.

Masakari instance evacuation


Implemented support for Masakari instance evacuation. Now, Masakari host monitor is deployed by default with Instances High Availability Service for OpenStack to provide automatic instance evacuation from failed instances.

Helm v3 for OpenStack operator

Implemented the usage of direct Helm 3 communication by the OpenStack operator. The usage of HelmBundles is dropped and automatic transition from Helm 2 to Helm 3 is performed during the MOS 21.3 to MOS 21.4 release update.

Cinder backend for Glance


Implemented the capability to configure Cinder backend for images through the OpenStackDeployment Custom Resource. The usage of Cinder backend for Glance enables the OpenStack clouds relying on third-party appliances for block storage to have images in one place.

Compact control plane for small Open vSwitch-based clouds


Added the capability to collocate the OpenStack control plane with the managed cluster master nodes through the OpenStackDeployment Custom Resource.


If the StackLight cluster is configured to run in the HA mode on the same nodes with the control plane services, additional manual steps are required for an upgrade to MOS 21.4 or for a greenfield deployment. For details, see known issue 17477.


Implemented full support for the SR-IOV with the Neutron OVS backend topology.

Large deployments support

Added support for large-scale deployments that number up to 200 nodes out of the box. The use case has been verified for core OpenStack services with OVS and non-DVR Neutron configuration on a dedicated hardware scale lab.

For a successful deployment, we recommend sticking to the optimal limit for the number of ports on gateway nodes that is 1500 ports per gateway node. This recommendation was confirmed during the testing and should be taken into account when planning large environments.



Implemented the capability to enable the BGP VPN service to allow for connection of OpenStack Virtual Private Networks with external VPN sites through either BGP/MPLS IP VPNs or E-VPN.

MOS API Reference

Published MOS API Reference to provide cloud operators with an up-to-date and comprehensive definition of the language they need to use to communicate with MOS OpenStack and Tungsten Fabric.

Learn more

MOS API Reference

Tungsten Fabric 2011 SR-IOV and DPDK


Implemented support for SR-IOV and DPDK with Tungsten Fabric 2011.

Improvements to StackLight alerting

Implemented the following improvements to StackLight alerting:

  • Added the following alerts:

    • CinderServiceDisabled that raises when a Cinder service is disabled on all hosts.

    • NeutronAgentDisabled that raises when a Neutron Agent is disabled on all hosts.

    • NeutronAgentOutage that raises when a Neutron Agent is down on all hosts where it is enabled.

    • NovaServiceDisabled that raises when a Nova service is disabled on all hosts.

    • TungstenFabricAPI401Critical that raises when Tungsten Fabric API responds with HTTP 401.

    • TungstenFabricAPI5xxCritical that raises when Tungsten Fabric API responds with HTTP 5xx.

  • Reworked the alert inhibition rules.

  • Reworked a number of alerts to improve alerting efficiency and reduce alert flooding.

  • Removed the inefficient *ServicesDownMajor, *ServicesDownMinor, *AgentsDownMajor, *AgentsDownMinor alerts.

Kibana improvement

Enhanced StackLight to send all OpenStack notifications to the notification index. Now, to view the previously called audit notifications, see the cadf Logger in the Kibana Notifications dashboard.