cinder #444

Supports: xenial bionic focal groovy hirsute impish


Cinder is the block storage service for the OpenStack.


The cinder charm deploys Cinder, the Block Storage (volume) service for OpenStack. The charm works alongside other Juju-deployed OpenStack services.



This section covers common and/or important configuration options. See file config.yaml for the full list of options, along with their descriptions and default values. See the Juju documentation for details on configuring applications.


The openstack-origin option states the software sources. A common value is an OpenStack UCA release (e.g. 'cloud:bionic-ussuri' or 'cloud:focal-victoria'). See Ubuntu Cloud Archive. The underlying host's existing apt sources will be used if this option is not specified (this behaviour can be explicitly chosen by using the value of 'distro').


This section includes two different deployment scenarios, each of which requires these applications to be present: keystone, nova-cloud-controller, nova-compute, rabbitmq-server, and a cloud database.

The database application is determined by the series. Prior to focal percona-cluster is used, otherwise it is mysql-innodb-cluster. In the example deployment below mysql-innodb-cluster has been chosen.

Ceph-backed storage

Cinder can be backed by Ceph, which provides volumes with scalability and redundancy.

Note: Ceph is the recommended storage method for production Cinder deployments.

These instructions assume a pre-existing Ceph cluster.

File cinder.yaml contains the following:

        block-device: None

Option block-device must be set to 'None' to disable the local block device.

Here, Cinder is deployed to a container on machine '1' and related to the Ceph cluster via the cinder-ceph subordinate charm:

juju deploy --to lxd:1 --config cinder.yaml cinder
juju deploy cinder-ceph
juju add-relation cinder-ceph:storage-backend cinder:storage-backend
juju add-relation cinder-ceph:ceph ceph-mon:client
juju add-relation cinder-ceph:ceph-access nova-compute:ceph-access

Proceed with a group of commands common to both scenarios:

juju add-relation cinder:identity-service keystone:identity-service
juju add-relation cinder:cinder-volume-service nova-cloud-controller:cinder-volume-service
juju add-relation cinder:amqp rabbitmq-server:amqp

juju deploy mysql-router cinder-mysql-router
juju add-relation cinder-mysql-router:db-router mysql-innodb-cluster:db-router
juju add-relation cinder-mysql-router:shared-db cinder:shared-db

LVM/iSCSI-backed storage

Cinder can be backed by storage local to the cinder unit, where a block device is used as an LVM physical volume. When a logical volume is created (openstack volume create) it is exported to a VM via iSCSI when needed (openstack server add volume).

Note: LVM/iSCSI is intended for testing and small Cinder deployments.

A sample cinder.yaml file's contents:

        block-device: sdc

Important: Make sure the designated block device exists and is not currently in use.

Deploy Cinder:

juju deploy --config cinder.yaml cinder

Proceed with the common group of commands from the Ceph scenario.

Note: It has been reported that the LVM storage method may not properly initialise the physical volume and volume group. See bug LP #1862392.

High availability

When more than one unit is deployed with the hacluster application the charm will bring up an HA active/active cluster.

There are two mutually exclusive high availability options: using virtual IP(s) or DNS. In both cases the hacluster subordinate charm is used to provide the Corosync and Pacemaker backend HA functionality.

See OpenStack high availability in the OpenStack Charms Deployment Guide for details.

Network spaces

This charm supports the use of Juju network spaces (Juju v.2.0). This feature optionally allows specific types of the application's network traffic to be bound to subnets that the underlying hardware is connected to.

Note: Spaces must be configured in the backing cloud prior to deployment.

API endpoints can be bound to distinct network spaces supporting the network separation of public, internal, and admin endpoints.

Access to the underlying MySQL instance can also be bound to a specific space using the shared-db relation.

For example, providing that spaces 'public-space', 'internal-space', and 'admin-space' exist, the deploy command above could look like this:

juju deploy --config cinder.yaml cinder \
   --bind "public=public-space internal=internal-space admin=admin-space shared-db=internal-space"

Alternatively, configuration can be provided as part of a bundle:

      charm: cs:cinder
      num_units: 1
        public: public-space
        internal: internal-space
        admin: admin-space
        shared-db: internal-space

Note: Existing cinder units configured with the os-admin-network, os-internal-network, or os-public-network options will continue to honour them. Furthermore, these options override any space bindings, if set.


This section covers Juju actions supported by the charm. Actions allow specific operations to be performed on a per-unit basis. To display action descriptions run juju actions cinder. If the charm is not deployed then see file actions.yaml.

  • openstack-upgrade
  • pause
  • remove-services
  • rename-volume-host
  • resume
  • security-checklist
  • volume-host-add-driver

Policy overrides

Policy overrides is an advanced feature that allows an operator to override the default policy of an OpenStack service. The policies that the service supports, the defaults it implements in its code, and the defaults that a charm may include should all be clearly understood before proceeding.

Caution: It is possible to break the system (for tenants and other services) if policies are incorrectly applied to the service.

Policy statements are placed in a YAML file. This file (or files) is then (ZIP) compressed into a single file and used as an application resource. The override is then enabled via a Boolean charm option.

Here are the essential commands (filenames are arbitrary):

zip override-file.yaml
juju attach-resource cinder
juju config cinder use-policyd-override=true

See Policy overrides in the OpenStack Charms Deployment Guide for a thorough treatment of this feature.


Please report bugs on Launchpad.

For general charm questions refer to the OpenStack Charm Guide.


(boolean) If True enables openstack upgrades for this charm via juju actions. You will still need to set openstack-origin to the new repository but instead of an upgrade running automatically across all units, it will wait for you to execute the openstack-upgrade action for this charm on each unit. If False it will revert to existing behavior of upgrading all units on config change.
(int) OpenStack Volume API listening port.
(string) The block devices on which to create LVM volume group. . May be set to None for deployments that will not need local storage (eg, Ceph/RBD-backed volumes). . This can also be a space-delimited list of block devices to attempt to use in the cinder LVM volume group - each block device detected will be added to the available physical volumes in the volume group. . May be set to the path and size of a local file (/path/to/file.img|$sizeG), which will be created and used as a loopback device (for testing only). $sizeG defaults to 5G
(int) This value dictates the number of replicas ceph must make of any object it stores within the cinder rbd pool. Of course, this only applies if using Ceph as a backend store. Note that once the cinder rbd pool has been created, changing this value will not have any effect (although the configuration of a pool can be always be changed within ceph itself or via the charm used to deploy ceph).
(string) Comma-separated list of key=value config flags. These values will be placed in the cinder.conf [DEFAULT] section.
(string) Database to request access.
(string) Username to request database access.
(boolean) Enable debug logging.
(string) The default volume type when creating a new volume without a volume type specified. It's useful only when multiple storage backends to be connected to Cinder. The corresponding volume type must be created after a deployment via API to take effect, e.g., `openstack volume type create VOLUME_TYPE --property volume_backend_name=BACKEND_NAME`
(boolean) Use DNS HA with MAAS 2.0. Note if this is set do not set vip settings below.
(string) If splitting cinder services between units, define which services to install and configure.
(string) Cloud instances provide ephemeral storage which is normally mounted on /mnt. . Providing this option will force an unmount of the ephemeral device so that it can be used as a Cinder storage device. This is useful for testing purposes (cloud deployment is not a typical use case).
(int) Newer storage drivers may require the v2 Glance API to perform certain actions e.g. the RBD driver requires requires this to support COW cloning of images. This option will default to v1 for backwards compatibility with older glance services.
(string) Default network interface on which HA cluster will bind to communication with the other members of the HA Cluster.
(int) Default multicast port number that will be used to communicate between HA Cluster nodes.
(int) Client timeout configuration in ms for haproxy, used in HA configurations. If not provided, default value of 90000ms is used.
(int) Connect timeout configuration in ms for haproxy, used in HA configurations. If not provided, default value of 9000ms is used.
(int) Queue timeout configuration in ms for haproxy, used in HA configurations. If not provided, default value of 9000ms is used.
(int) Server timeout configuration in ms for haproxy, used in HA configurations. If not provided, default value of 90000ms is used.
(string) Apply system hardening. Supports a space-delimited list of modules to run. Supported modules currently include os, ssh, apache and mysql.
(boolean) Enable the image volume cache. Supported on OpenStack Ocata and newer.
(int) Max number of entries allowed in the image volume cache. 0 means unlimited. Supported on OpenStack Ocata and newer.
(int) Max size of the image volume cache in GB. 0 means unlimited. Supported on OpenStack Ocata and newer.
(string) Used by the nrpe-external-master subordinate charm. A string that will be prepended to instance name to set the host name in nagios. So for instance the hostname would be something like 'juju-myservice-0'. If you are running multiple environments with the same services in them this allows you to differentiate between them.
(string) A comma-separated list of nagios servicegroups. If left empty, the nagios_context will be used as the servicegroup
(string) A comma-separated list of oslo notification topics. If left empty, the default topic 'cinder' is going to be used.
(string) Repository from which to install. May be one of the following: distro (default), ppa:somecustom/ppa, a deb url sources entry, or a supported Ubuntu Cloud Archive e.g. . cloud:<series>-<openstack-release> cloud:<series>-<openstack-release>/updates cloud:<series>-<openstack-release>/staging cloud:<series>-<openstack-release>/proposed . See for info on which cloud archives are available and supported. . NOTE: updating this setting to a source that is known to provide a later version of OpenStack will trigger a software upgrade unless action-managed-upgrade is set to True.
(string) The hostname or address of the admin endpoints created for cinder in the keystone identity provider. . This value will be used for admin endpoints. For example, an os-admin-hostname set to '' with ssl enabled will create two admin endpoints for cinder: .$(tenant_id)s and$(tenant_id)s
(string) The IP address and netmask of the OpenStack Admin network (e.g. . This network will be used for admin endpoints.
(string) The hostname or address of the internal endpoints created for cinder in the keystone identity provider. . This value will be used for internal endpoints. For example, an os-internal-hostname set to '' with ssl enabled will create two internal endpoints for cinder: .$(tenant_id)s and$(tenant_id)s
(string) The IP address and netmask of the OpenStack Internal network (e.g. . This network will be used for internal endpoints.
(string) The hostname or address of the public endpoints created for cinder in the keystone identity provider. . This value will be used for public endpoints. For example, an os-public-hostname set to '' with ssl enabled will create two public endpoints for cinder: .$(tenant_id)s and$(tenant_id)s
(string) The IP address and netmask of the OpenStack Public network (e.g. . This network will be used for public endpoints.
(string) If true, charm will attempt to overwrite block devices containing previous filesystems or LVM, assuming it is not in use.
(boolean) If True enables IPv6 support. The charm will expect network interfaces to be configured with an IPv6 address. If set to False (default) IPv4 is expected. . NOTE: these charms do not currently support IPv6 privacy extension. In order for this charm to function correctly, the privacy extension must be disabled and a non-temporary address must be configured/available on your network interface.
(string) Username to request access on rabbitmq-server.
(string) RabbitMQ virtual host to request access on rabbitmq-server.
(string) OpenStack Region
(boolean) If True, charm will attempt to remove missing physical volumes from volume group, if logical volumes are not allocated on them.
(boolean) If True, charm will attempt to remove missing physical volumes from volume group, even when logical volumes are allocated on them. This option overrides 'remove-missing' when set.
(boolean) Cinder can optionally restrict the key it asks Ceph for to only be able to access the pools it needs.
(string) SSL CA to use with the certificate and key provided - this is only required if you are providing a privately signed ssl_cert and ssl_key.
(string) SSL certificate to install and use for API ports. Setting this value and ssl_key will enable reverse proxying, point Cinder's entry in the Keystone catalog to use https, and override any certificate and key issued by Keystone (if it is configured to do so).
(string) SSL key to use with certificate specified as ssl_cert.
(boolean) Openstack mostly defaults to using public endpoints for internal communication between services. If set to True this option will configure services to use internal endpoints where possible.
(boolean) If True then use the resource file named 'policyd-override' to install override YAML files in the service's policy.d directory. The resource file should be a ZIP file containing at least one yaml file with a .yaml or .yml extension. If False then remove the overrides.
(boolean) Setting this to True will allow supporting services to log to syslog.
(boolean) Enable verbose logging.
(string) Virtual IP(s) to use to front API services in HA configuration. . If multiple networks are being used, a VIP should be provided for each network, separated by spaces.
(int) Default CIDR netmask to use for HA vip when it cannot be automatically determined.
(string) Default network interface to use for HA vip when it cannot be automatically determined.
(string) Name of volume group to create and store Cinder volumes.
(string) Time period for which to generate volume usages. The options are hour, day, month, or year.
(float) The CPU core multiplier to use when configuring worker processes for this service. By default, the number of workers for each daemon is set to twice the number of CPU cores a service unit has. This default value will be capped to 4 workers unless this configuration option is set.