[SOLVED] LVM on LUKS with systemd-boot: password asked but can't boot

Jojonintendo · 2016-02-22 20:21:06

Hi,

I've been spending the last couple of days trying to get an encrypted LVM system, but I can't seem to get it right.

System is like this:

/dev/sda1 - for systemd-boot
/dev/sda2 - encrypted LVM

"/dev/sda1" is mounted in "/boot"
Inside LVM is:

/dev/CryptArch/swapvol
/dev/CryptArch/rootvol - ext4
/dev/CryptArch/homevol - ext4

I managed to install everything following the wiki for the LVM part, since I'm a complete beginner in both LVM and LUKS.
The problem is that when booting, systemd asks me the password, but then can't move on and shows something like

mount: unknown filesystem type 'LVM2_member'

Now for my config files.
/boot/loader/entries/arch-encrypted.conf

options cryptdevice=UUID=</dev/sda2 UUID, same as in fstab>:CryptArch-rootvol root=/dev/mapper/CryptArch-rootvol quiet rw

mkinitcpio.conf

HOOKS="...block keymap encrypt lvm2 filesystems ..."

Strange thing is blkid shows something like

/dev/mapper/lvm ... TYPE=LVM2_member

which is the error I get when booting, but I want /dev/mapper/CryptArch-rootvol to be mounted. I tried setting "root=" to UUID of /dev/mapper/CryptArch-rootvol, but systemd can't even find the partition, same when I put /dev/CryptArch/rootvol.
I'm pretty sure the problem is a little thing in a config file, but I can't find it, I tried almost every combination I could think of. I also applied many solutions that I found on the forum, but it only got me this far (I couldn't even input password yesterday ).

Also, in this section of the wiki I'm confused about root, I don't understand the difference between dmname and volumegroup-logicalvolume. My VG is CryptArch, and LV are rootvol, homevol and swapvol.

I can manually mount everything to get other config files if needed.

Thanks.

Last edited by Jojonintendo (2016-02-23 08:04:42)

Strike0 · 2016-02-22 22:29:56

Jojonintendo wrote:

/boot/loader/entries/arch-encrypted.conf

options cryptdevice=UUID=</dev/sda2 UUID, same as in fstab>:CryptArch-rootvol root=/dev/mapper/CryptArch-rootvol quiet rw

For one, try a dmname different from "CryptArch-rootvol", e.g.

options cryptdevice=UUID=</dev/sda2 UUID from blkid>:CryptArch root=/dev/mapper/CryptArch-rootvol quiet rw

Second, double-check the fstab root is indeed /dev/mapper/CryptArch-rootvol.

Jojonintendo · 2016-02-23 08:04:15

Ok, I changed the dmname before booting and that's it. I didn't worry about "cryptsetup=" parameter because it was asking the password when booting, so I thought it was good. I still don't really understand "dmname" vs "vgname-lvname", but my issue is indeed solved. Many thanks!

Strike0 · 2016-02-23 15:24:03

You're welcome. Good it works. Problem apparently a name race condition. If you look at the "blkid" output of your booted system, it will have a "/dev/mapper/CryptArch-rootvol" entry. That is the LVM vg-lv mapped for the device by virtue of your LVM setup. Previously the :dmname already occupied the same /dev/mapper entry when lvm wanted to activate the volumes.

Jojonintendo · 2016-02-23 16:01:39

OK, I think I get where the problem was. Thanks again for taking time to help and explain me

Arch Linux

#1 2016-02-22 20:21:06

[SOLVED] LVM on LUKS with systemd-boot: password asked but can't boot

#2 2016-02-22 22:29:56

Re: [SOLVED] LVM on LUKS with systemd-boot: password asked but can't boot

#3 2016-02-23 08:04:15

Re: [SOLVED] LVM on LUKS with systemd-boot: password asked but can't boot

#4 2016-02-23 15:24:03

Re: [SOLVED] LVM on LUKS with systemd-boot: password asked but can't boot

#5 2016-02-23 16:01:39

Re: [SOLVED] LVM on LUKS with systemd-boot: password asked but can't boot

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