I still have no working systemd lvm on luks installation, but I read a lot in the arch wiki and I think it depends on the case but it can get really complex.
My case is not this difficult, because I use lvm on luks on only one hard drive.
I will try the updated installer on the weekend again, and then I will write you a longer message. Because I don't have time to do it before.
In short: if you use lvm and luks together you need to modify mkinitcpio and you have to set kernel parameters in the bootloader.
About crypttab: "Note: When using systemd-boot and the sd-encrypt
hook, if a non-root partition's passphrase is the same as root's, there
is no need to put that non-root partition in crypttab due to passphrase
and then there are two special cases:
- Suspend to disk known as hibernate
- and if you use a SSD Trim
I want to use both! But to use Trim is not recommended because of complex security issues.
Thanks for this great installer. Will write you again on the weekend
PS: don't forget the mkinitcpio hooks are worked off in order. This means:
- lvm on luks need "encrypt lvm2"
- luks on lvm need "lvm2 encrypt"
and if you want to use resume for hibernate you need for lvm on luks "encrypt lvm2 resume"
and if you want that systemd is handling this stuff what is (I think) recommended you need "systemd sd-encrypt sd-lvm2 resume"