diff --git a/FAQ b/FAQ index 231ca019..cfa9df7b 100644 --- a/FAQ +++ b/FAQ @@ -808,7 +808,7 @@ A. Contributors For device set-up, do the following: - cryptsetup open --type plain -d /dev/urandom /dev/ target + cryptsetup open --type plain -d /dev/urandom /dev/ to_be_wiped This maps the container as plain under /dev/mapper/to_be_wiped with a random password. For the actual wipe you have several options. @@ -828,6 +828,29 @@ A. Contributors Remove the mapping at the end and you are done. + * 2.20 How to I wipe only the LUKS header? + + This is not the emergency wipe procedure. That is in Item 5.4. This procedure + is intended to be used when the data should stay intact, e.g. when you change + your LUKS container to use a detached header and want to remove the old one. + + Most safe way is this (backup is still a good idea): + + 01) Determine header size in 512 Byte sectors with "luksDump": + + cryptsetup luksDump + +-> ... + Payload offset: + ... + + 02) Take the result number and write number * 512 zeros to the start of the + device, e.g. like this: + + dd bs=512 count= if=/dev/zero of= + + That is it. + 3. Common Problems