Current Series Release Notes

21.0.0.0rc1

Prelude

The Kolla 21.0.0 (Flamingo) release modernises the base operating systems and core infrastructure shipped by the containers. Highlights include:

  • Rocky Linux 10 replaces Rocky Linux 9 as the only supported Rocky base image, removing the Delorean/CentOS Cloud SIG dependency and tightening RPM repository handling via repos.yaml (including a new versioned Erlang source for aarch64).

  • Data-plane services received major upgrades: MariaDB now tracks the 11.4 LTS series with the upstream health check script and the legacy clustercheck image removed, ProxySQL moves to 3.x, Bifrost consumes Ansible 11, RabbitMQ advances to 4.1, and Gnocchi is updated to 4.7.0.

  • Observability components were refreshed with Fluentd 6.x LTS, OpenSearch/OpenSearch Dashboards 3.x, broad Prometheus exporter and infrastructure bumps (etcd, helm, letsencrypt-lego), and the retirement of the collectd, telegraf, and prometheus-ovn-exporter images.

  • The container portfolio was streamlined: support landed for the ironic-pxe-filter image and neutron-metadata-agent wrapper scripts, while dormant services such as ironic-inspector and Venus were dropped.

New Features

  • Added new MariaDB container health check script healthcheck.sh. This script is from official docker images of MariaDB.

    This script is planned to replace current health check script clustercheck.sh to keep compatibility with newer MariaDB releases.

  • Adds ironic-pxe-filter container image.

  • The neutron wrapper scripts, which were introduced in I679ac66186d457ae53f89469fe22c5662089019a, are now included in the neutron-metadata-agent container, making it possible to run haproxy processes as separate containers.

  • Adds support for configuring RPM distributions repositories using repos.yaml functionality.

  • Adds support for Rocky Linux 10 as a base container image. From the 2025.2 release onward, Rocky Linux 10 is the only supported Rocky Linux major version.

Upgrade Notes

  • Backup files are now stored in timestamped directories and have new filenames. This does not affect restore, as Kolla Ansible does not support automated restore; users perform restores manually. A new full backup is recommended after upgrade to ensure incremental backups work correctly.

  • Upgraded ProxySQL to version 3.0.x.

  • Debian container image builds now use Epoxy (2025.1) repositories of Debian OpenStack.

  • Debian container image builds now use bookworm suite for RabbitMQ installation.

  • Drops requirement to use Delorean/CentOS Cloud SIG repositories in rpm-based images.

  • Removes support for building ironic-inspector images following retirement in Ironic project.

  • Support for building neutron-linuxbridge-agent container image has been dropped following removal in Neutron.

  • Support for building Venus container images has been dropped due to the project’s inactivity and the Horizon plugin build failures it caused.

  • Switches Erlang RPMs on aarch64 to a versioned Erlang 27 repository, due to Fedora COPR not supporting multiple package versions in one repo.

  • Updates Fluentd to the 6.x LTS series.

  • Gnocchi version has been updated to 4.7.0.

  • Updates MariaDB to the 11.4 LTS release, which is supported until 29 May 2029.

  • Updates OpenSearch and OpenSearch Dashboards to version 3.x.

  • Updates RabbitMQ to version 4.1.

  • Dropped support for building MariaDB clustercheck container image as it will not be compatible with MariaDB 11.4 (the next LTS version).

  • Removes the prometheus-ovn-exporter image because it is unused by Kolla Ansible and the upstream repository was archived in December 2024.

  • Rocky Linux 9 is no longer supported as a base container image, so deployments using Rocky Linux should migrate to Rocky Linux 10.

  • The telegraf image relied on Rocky Linux 9-only packages and is therefore unavailable for Rocky Linux-based builds.

  • Updates monitoring and key infrastructure components to their latest supported versions. This covers several Prometheus exporters as well as etcd, helm, and letsencrypt-lego.

    • etcd: 3.5.16 -> 3.6.5

    • helm: 3.16.3 -> 3.19.0

    • letsencrypt-lego: 4.20.4 -> 4.27.0

    • prometheus-blackbox-exporter: 0.25.0 -> 0.27.0

    • prometheus-cadvisor: 0.49.2 -> 0.53.0

    • prometheus-elasticsearch-exporter: 1.8.0 -> 1.9.0

    • prometheus-memcached-exporter: 0.15.0 -> 0.15.3

    • prometheus-mysqld-exporter: 0.16.0 -> 0.17.2

    • prometheus-node-exporter: 1.8.2 -> 1.9.1

    • prometheus-server: 3.2.1 -> 3.5.0 (LTS)

    Additionally, prometheus-server now tracks the Long-Term Support (LTS) channel to provide longer maintenance windows.

Deprecation Notes

  • Deprecates support for building collectd and telegraf images.

Bug Fixes

  • Fixes incremental MariaDB backups by switching to directory-based base backups, following official Mariabackup recommendations. LP#2111620

  • Ensures Kolla uses only configured APT mirror on Ubuntu for full source control. LP#2112140

  • Fixes set_configs.py not detecting removed config files during –check, which prevented container restart when needed. LP#2114173

  • Fixed missing metrics in Prometheus libvirt exporter.

    The Prometheus libvirt exporter has been bumped from v1.6.0 to v2.2.0. This restores some metrics that were lost when the exporter source was changed in a previous release.

    LP#2120639.

  • Fix using Cinder as Glance image store when Cinder uses a FC or iSCSI backend by adding the missing lsscsi package to glance-api. LP#2111828

  • Fix neutron-l3-agent image builds on Rocky Linux by removing dibbler-client dependency. The package is no longer used in Neutron. LP#2112575