So I am trying to get my disk encrypted with the nuke option... I cannot find the syntax!! I have the below, but I dont want to format my exisitig install:

cryptsetup -c aes-xts-plain -s 512 -h sha256 -y luksFormat /dev/sda1


The above will format the drive.

How do I get my drive encrypted with a power on pass and nuke pass???

Thanks for any help all!!!