Creating a block device is as simple as specifying the size and a name for the block device being created:
undercloud# openstack volume create --size 1 my_volume
This command created a virtual block device that is 1 GB of storage space. To see the devices, use the list command:
undercloud# openstack volume list
The volume will be listed with information about it. As with the components already covered, the admin user can see all volumes that are in Cinder and non-privileged users see only the Cinder volumes in their project. When volumes are created, they cycle through a progression of states that indicate the status of the new block device. When the status reaches Available, it is ready to be attached to an instance.