how to hard restart amazon kindle oasis

"""
I request you please do hard restart of 40 seconds.

1. Connect the device to a power adapter, if available.
2. Press and hold the Power button for 40 seconds. If the device
restarts before 40 seconds has passed, release the Power button.
3. Press the Power button again to restart your Kindle.

Please let me know once you have done.
"""

how to rename crypted device in crypttab

according to n.r.,

"""
Replace OLD_NAME with NEW_NAME in /etc/crypttab, and then:

# dmsetup rename OLD_NAME NEW_NAME
# update-initramfs -c -t -k all
# update-grub
# reboot
"""

references:

- https://unix.stackexchange.com/questions/81011/how-to-change-the-name-an-encrypted-full-system-partition-is-mapped-to