All of the posts that I can find regarding encrypted-data recovery regard specific situations. I currently have functioning partitions and directories, but would like to maximise my chances of recovering data should something go wrong (in addition to my back ups). What information (such as keys, passphrases, configuration etc.) should I keep in cold storage given the following setup?
Ubuntu root is installed on a LUKS-encrypted drive. I have a second HDD that is also LUKS-encrypted and is set up to automatically mount upon login. Additionally my home directory is mounted with ecryptfs.
I know that for ecryptfs I should be storing the output of ecryptfs-unwrap-passphrase, but what should be done for each of the LUKS partitions? I vaguely remember that there is some other passphrase that should be stored in case particular partition header information is corrupted.
Thanks for your help. As an aside, should anyone be interested in the cold storage, I plan to simply create level H (high error correction) QR codes for printing to paper along with the actual data as text.