Cinder is the block storage service for the Openstack project. . This charm provides a Ceph storage backend for Cinder
Ceph Storage Backend for Cinder
This charm provides a Ceph storage backend for use with the Cinder
charm; this allows multiple Ceph storage clusters to be associated
with a single Cinder deployment, potentially alongside other storage
backends from other vendors.
juju deploy cinder juju deploy -n 3 ceph juju deploy cinder-ceph juju add-relation cinder-ceph cinder juju add-relation cinder-ceph ceph
The cinder-ceph charm allows the replica count for the Ceph storage
pool to be configured. This must be done in advance of relating to
the ceph charm:
juju set cinder-ceph ceph-osd-replication-count=3 juju add-relation cinder-ceph ceph
By default, the replica count is set to 2 replicas. Increasing this
value increases data resilience at the cost of consuming most real
storage in the Ceph cluster.
Defines a relative weighting of the pool as a percentage of the total amount of data in the Ceph cluster. This effectively weights the number of placement groups for the pool created to be appropriately portioned to the amount of data expected. For example, if the ephemeral volumes for the OpenStack compute instances are expected to take up 20% of the overall configuration then this value would be specified as 20. Note - it is important to choose an appropriate value for the pool weight as this directly affects the number of placement groups which will be created for the pool. The number of placement groups for a pool can only be increased, never decreased - so it is important to identify the percent of data that will likely reside in the pool.
This value dictates the number of replicas ceph must make of any object it stores withing 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 it can be changed in ceph by manually configuring your ceph cluster).