olenkoI think I just nuked my home partition
chameleonGiven that the UUID changed, you almost certainly made a new LUKS container, overwriting the old one. That's bad, because the LUKS header is the only source of the actual encryption key that was used, and making a new one will overwrite both the main header as well as its backup copy immediately. Your password/keyfile/whatever is merely used to decrypt the part of the header that has the actual encryption key, and that's gone in that case.
Unless you have access to a header backup from before that, there's a fairly strong chance it's irrecoverable. I'd suggest going through any archives you might have to see if you have such a backup - most of the instructions on the Gentoo wiki encourage making one, so you might have made one through the power of copying & pasting instructions. Should be a file of around 16MB.
Sadly, I don’t have a backup of the header. But I know the password that was used to decrypt the partition. Anyway, from the things you said, I can conclude that it might be irrecoverable.
astrskWhat are the chances the header is stored in the partition map? Could you use testdisk to try and recover the old partition map and its data?
I think the header is stored in the partition map but just like chameleon said, it has been overwritten by the new one, that I created by accident.
Right, well testdisk has worked wonders in the past for me. It might worth a try especially if this is a spinning rust drive. It has helped me recover broken partitions and lost files so if you know where you’re looking you just might have a chance. I’m no expert but it seems like one of your last options with all the info provided. Best of luck!
I ran it, but no luck! In any way, I have already wiped the partition because I heard it was irrecoverable.