Block storage

Traditional persistent storage is provided to OpenStack workloads through the Cinder block storage component. The life cycle of Cinder volumes is maintained independent of compute instances, and volumes may be attached or detached to one or more compute instances to provide a backing store for filesystem-based storage.

OpenStack ships with a reference implementation of Cinder, which leverages local storage on the host and uses LVM as well as the ability to use iSCSI to share a block device attached to a Cinder storage node that can use its storage for instances. This implementation lacks high availability, and it is typically only used in test environments. Production deployments tend to leverage a software-based or hardware-based block storage solution, such as Ceph or NetApp, chosen based on performance and availability requirements.