The 21.10 OpenStack Charms release includes updates for the charms described on the Supported charms page. As of this release, the project consists of 62 stable charms.

For the list of bugs resolved in this release refer to the 21.10 milestone in Launchpad.

For scheduling information of past and future releases see the Release schedule.

General charm information is published in the OpenStack Charm Guide (this guide) which ultimately supersedes Release Notes contents.


Always upgrade to the latest stable charms before making any major changes to your cloud and before filing bug reports. Refer to section Upgrading charms below for details.

Table of contents:

New stable charms

Two new stable charms are now available.


The cinder-lvm charm enables an LVM backend for Cinder. It is a subordinate charm used in conjunction with the cinder principle charm. The cinder-lvm charm deprecates the LVM functionality of the cinder charm. A migration path is available here: LVM support in cinder charm: migration to cinder-lvm.


The cinder-netapp charm enables a NetApp backend for Cinder. It is a subordinate charm used in conjunction with the cinder principle charm.

New stable charm features

With each new feature, there is a corresponding example bundle in the form of a test bundle, and/or a section in the OpenStack Charms Deployment Guide, that details its usage. Test bundles are located in the src/tests/bundles directory of the relevant charm repository (see all charm repositories).

glance charm: external S3 compatible storage support

The glance charm has acquired some new configuration options:

  • s3-store-host

  • s3-store-access-key

  • s3-store-secret-key

  • s3-store-bucket

These options are used to set an external S3 compatible storage backend for Glance. S3 support in the charm is enabled only for Ussuri and later releases.

nova-compute charm: number of hosted VMs

The nova-compute charm has a new action: instance-count.

This action returns the number of VMs hosted on a nova-compute unit, whether they be running, suspended, or stopped.

ceilometer-agent charm: new polling configuration options

The ceilometer-agent charm has two new options: polling-interval and enable-all-pollsters.

These options are used to control the polling frequency and the set of meters collected by the compute polling agent. The meters that can be collected via enable-all-pollsters are listed in Compute meters documentation with ‘Pollster’ in the origin column.

cinder-purestorage charm: new configuration options

The cinder-purestorage charm has a number of new configuration options:

  • eradicate-on-delete

  • automatic-max-oversubscription

  • iscsi-cidr

  • use-chap

  • use-replication

  • replication-target-name

  • replication-target-address

  • replication-target-api-token

  • replication-type

  • replication-sync-uniform

  • replica-interval

  • replica-retention-short

  • replica-retention-per-day

  • replica-retention-long

  • replication-pgname

  • replication-pod

  • use-image-cache

  • image-volume-cache-max-size-gb

  • image-volume-cache-max-count

These options are used to enable and configure Cinder replication and Glance Image Cache for Cinder, along with a number of Pure Storage driver specific features.

Please refer to the cinder-purestorage charm documentation for a description of these configuration options.

neutron-api charm: FWaaS option

The neutron-api charm has a new configuration option: enable-fwaas.

This option controls the enablement of the Neutron FWaaS service. It defaults to ‘true’ to retain past behaviour but only takes effect for OpenStack releases older than Victoria. Setting it to ‘false’ will disable the service on all neutron-api units.

See deprecation notice neutron-api charm: FWaaS removal for background information.

ceph-mon charm: disk capacity alert threshold configuration

The ceph-mon charm has two new configuration options: monitor-data-available-warning and monitor-data-available-critical.

These options can be used to configure the thresholds at which the Ceph cluster goes into HEALTH_WARN and HEALTH_ERR states based on the available disk capacity.

ceph-radosgw charm: Beast HTTP frontend

The ceph-radosgw charm has a new configuration option: http-frontend.

With the availability of the Beast frontend the ceph-radosgw charm now supports the selection of what Ceph RADOS Gateway HTTP frontend to use. Starting with Ceph Octopus the default value (of option http-frontend) is ‘beast’, and for older releases ‘civetweb’ will continue to be used.

designate charm: new options for creating DNS records

The designate charm has some new configuration options:

  • default-ttl

  • default-soa-minimum

  • default-soa-refresh-min

  • default-soa-refresh-max

  • default-soa-retry

These options are used to define default settings for the creation of DNS records. They have no effect on existing records.

nova-compute charm: new options for neutron physnets NUMA affinity

The nova charm has some new configuration options:

  • neutron-physnets

  • neutron-tunnel

These options are used to define NUMA affinity for neutron physnets and tunneled networks.

ceph-osd charm: new action to display availability zones information

The ceph-osd charm has a new action: get-availability-zone.

This action returns availability zone information that contains CRUSH structure information. Specifically ‘rack’, ‘row’, etc.

manila charm: new relation nrpe-external-master to nrpe charm

The manila charm has a new relation to nrpe charm.

This relation adds nrpe checks for services managed by manila charm to be monitored with Nagios.

ceph-mon charm: new parameter for list-pools action

The ceph-mon charm’s list-pools action has a new format parameter that accepts the following values:

  • ‘text’ - provides less information [default]

  • ‘text-full’ - provides more information in json with indents

  • ‘json’ - provides more information in json

The default of ‘text’ maintains the behaviour of previous charm versions.

neutron-gateway charm: new actions to display routers/networks/loadbalancers

The neutron-gateway charm has three new actions that enable the listing of Neutron resources hosted on a neutron-gateway unit:

  • show-routers - lists Neutron routers

  • show-dhcp-networks - lists DHCP networks

  • show-loadbalancers - lists LBaaS v2 loadbalancers

cinder charm: image volume caching

The cinder charm has the following new configuration options:

  • image-volume-cache-enabled

  • image-volume-cache-max-size-gb

  • image-volume-cache-max-count

These options allow the enablement of a Cinder image cache as well as set its maximum size and its maximum number of entries. These options are supported on OpenStack Ocata and newer.

ceph-mon charm: new action to display quorum status

The ceph-mon charm has a new action: get-quorum-status.

This action returns some distilled information from the ceph quorum_status command. It is primarily intended for verifying which ceph-mon units are online.

barbican charm: new options for request and secret sizes

The barbican charm has some new configuration options:

  • max-allowed-request-size

  • max-allowed-secret-size

These options are used to limit the maximum size of a request sent to the barbican-api service and a secret respectively. Scenarios where the users will need to upload large certificate chains the 20 kB limit will need to be increased otherwise the barbican-api service will reply with a 413 Error “Request Entity Too Large”.

OVN chassis charms: New option to influence scheduling of gateways

Both the ovn-chassis and ovn-dedicated-chassis charms have a new configuration option: prefer-chassis-as-gw.

For a deployment with multiple named OVN chassis applications, this option specifies which application should have its units preferred when scheduling gateways. It defaults to ‘false’ which will make the Cloud Management System (CMS) schedule gateways to any chassis with appropriate bridge mappings configured.

Documentation updates

A summary of the most significant documentation updates is given below.

  • In the OpenStack Charm Guide (aka “charm guide”):

    • The guide has been refactored to better reflect the Diataxis framework.

    • A section on cloud operations has been started.

  • In the OpenStack Charms Deployment Guide (aka “deploy guide”):

    • A page on OpenStack Ironic support has been added.

    • The install section has been updated to OpenStack Xena (with OVS bridge).

  • Full review of these charms: ceph-dashboard, cinder-lvm, cinder-netapp, neutron-gateway, nova-cloud-controller, nova-compute, and openstack-loadbalancer.

New tech-preview charms

Five new tech-preview charms are now available.


The ceph-dashboard charm deploys the Ceph Dashboard, a built-in web-based Ceph management and monitoring application.


The openstack-loadbalancer charm provides a load balancer for units of an OpenStack application. It can manage multiple such applications providing that each application supports the load balancer charm. It has the potential therefore of deprecating the current practice of deploying hacluster for each application under HA.

Ironic charms

The following tech-preview charms are available for the deployment of OpenStack Ironic:

  • ironic-api

  • ironic-conductor

  • neutron-api-plugin-ironic

Ironic provisions bare metal, as opposed to virtual, machines.

Informational notices

neutron-openvswitch charm: DHCP service restarts in DPDK environments

When DPDK is enabled and DHCP is running locally on a compute node, the neutron-dhcp-agent service now restarts during charm upgrades or when any configuration change that triggers the restart of the neutron-openvswitch agent.

OVN chassis charms: Change of behaviour for gateway chassis scheduling

To improve the control of gateway chassis scheduling for the cloud operator, a new configuration option was introduced as detailed in OVN chassis charms: New option to influence scheduling of gateways. A side effect of this change is that the CMS may reschedule gateway chassis for its routers on charm upgrade. Since OVN routers are HA by default, the impact should be minimal.

Deprecation notices

Xenial series

The ‘xenial’ series will be removed from general gate testing following this release and maintenance will be limited to critical and high security fixes only. Users are strongly encouraged to upgrade their clouds to a newer platform.

Barbican SoftHSM2 Plugin

The barbican-softhsm test charm is now deprecated and will have no further releases. Support has ended for it. Please use the barbican-vault charm instead.

neutron-api charm: FWaaS removal

The Firewall-as-a-Service (FWaaS) OpenStack project is retired and will not receive updates beyond v16.0.0. Consequently, the neutron-api charm will no longer make this service available starting with OpenStack Victoria.

See new charm feature neutron-api charm: FWaaS option resulting as a consequence of this.

Tempest charm

The tempest test charm is now deprecated and will have no further releases. Support has ended for it. Please use the tempest Python package instead.

Built-in Cinder LVM backend

The LVM-based volume feature of the cinder charm is now deprecated. This functionality has been replaced by the new subordinate cinder-lvm charm.

Issues discovered during this release cycle

OVN and SR-IOV: servicing external DHCP and metadata requests

When instances are deployed with SR-IOV networking in an OVN deployment a change of configuration may be required to retain servicing of DHCP and metadata requests.

If your deployment has SR-IOV instances, make sure that at least one of the OVN chassis named applications has the prefer-chassis-as-gw configuration option set to ‘true’.

The root of the issue is in how Neutron handles scheduling of gateway chassis for L3 routers and external services differently, and is tracked in bug LP #1946456.

Upgrading charms

Upgrading charms will making available new features and bug fixes. However, the latest stable charm revision should also be used prior to making any topological changes, application migrations, workload upgrades, or series upgrades. Bug reports should also be filed against the most recent revision.

Note that charm upgrades and OpenStack upgrades are functionally different. For instructions on performing the different upgrade types see Upgrades overview in the OpenStack Charms Deployment Guide.