Cinder provides persistent storage management for the virtual machine's hard drives. Unlike ephemeral storage, virtual machines backed by Cinder volumes can be easily live-migrated and evacuated. In prior OpenStack releases, block storage was a part of the compute service in OpenStack nova-volume. Within its overwhelmed new features, block storage service has been evolved and taken a separate spot in the OpenStack ecosystem so renamed as Cinder. Under the hood, volumes expose a raw block of storage that can be attached to instances and can store data permanently. The attached volume appears as an additional hard-drive within the virtual machine. To use the attached volume within a virtual machine, it must be first partitioned and laid with a filesystem and mounted on to the filesystem hierarchy on the virtual machine.
Cinder uses iSCSI, NFS, and fiber channels to present...