# blkpr > Register, reserve, release, preempt, and clear persistent reservations on a block device that supports Persistent Reservations. > More information: . - Register (command) a new reservation with a given key on a given device: `blkpr {{[-c|--command]}} register {{[-k|--key]}} {{reservation_key}} {{path/to/device}}` - Set the type of an existing reservation to exclusive access: `blkpr -c reserve {{[-k|--key]}} {{reservation_key}} {{[-t|--type]}} exclusive-access {{path/to/device}}` - Preempt the existing reservation with a given key and replace it with a new reservation: `blkpr -c preempt {{[-K|--oldkey]}} {{old_key}} {{[-k|--key]}} {{new_key}} {{[-t|--type]}} write-exclusive {{path/to/device}}` - Release a reservation with a given key and type on a given device: `blkpr -c release {{[-k|--key]}} {{reservation_key}} {{[-t|--type]}} {{reservation_type}} {{path/to/device}}` - Clear all reservations from a given device: `blkpr -c clear {{[-k|--key]}} {{key}} {{path/to/device}}`