mjhjmtu

My system was installed with the Antergos installer and it runs encrypted GRUB. This works fine, just have to insert decryption key twice.

Then I added LVM and created three LVM volumes, boot root and swap. Now I want to update my GRUB with this LVM setup so I can choose to boot the second OS from LVM or just boot Arch.

NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sda 8:0 0 465.8G 0 disk 
├─sda1 8:1 0 65.2G 0 part 
│ └─luks 254:0 0 65.2G 0 crypt /
├─sda2 8:2 0 3.7G 0 part 
│ └─luks-14a10aeb-01ec-44f4-b908-0c09685a03ed 254:4 0 3.7G 0 crypt /run/media/thijs/74ec47c2-64ed-4fe5-a965-a5e414b7a129
└─sda3 8:3 0 396.9G 0 part 
 ├─triagia-kaliboot 254:1 0 500M 0 lvm /run/media/thijs/f1eb6904-c17e-40b7-8740-60e67b8d04de
 ├─triagia-kaliroot 254:2 0 50G 0 lvm 
 │ └─luks-26028d27-8a95-41c3-9d80-9415b8c170dc 254:6 0 50G 0 crypt /run/media/thijs/65c769fd-ea4a-4854-928c-3c28f15745aa
 └─triagia-kaliswap 254:3 0 4G 0 lvm 
 └─luks-a0fa8f9e-e6d0-42d7-b54c-7c275ddc328a 254:5 0 4G 0 crypt 

But when I use grub-mkconfig, the script never finds the boot partition in the LVM. I've used vgscan and vgchange to make them active and mounted the LVM volumes but still grub-mkconfig only reports the boot on sda1.

Research points a lot to taking /boot out of the LVM but I don't like that. I'd add the needed GRUB config manually but I couldn't find an example.

Volumes:

 --- Logical volume ---
 LV Path /dev/triagia/kaliboot
 LV Name kaliboot
 VG Name triagia
 LV UUID e68eqU-zP3Q-YnwY-ds6M-MG34-zAB5-VhZcAQ
 LV Write Access read/write
 LV Creation host, time conDoin, 2015-08-21 17:50:52 +0200
 LV Status available
 # open 0
 LV Size 500.00 MiB
 Current LE 125
 Segments 1
 Allocation inherit
 Read ahead sectors auto
 - currently set to 256
 Block device 254:0

 --- Logical volume ---
 LV Path /dev/triagia/kaliroot
 LV Name kaliroot
 VG Name triagia
 LV UUID Bco7iM-ZlQR-NyeI-Nl1r-N1IK-kooC-oBCfV6
 LV Write Access read/write
 LV Creation host, time conDoin, 2015-08-21 17:51:09 +0200
 LV Status available
 # open 0
 LV Size 50.00 GiB
 Current LE 12800
 Segments 1
 Allocation inherit
 Read ahead sectors auto
 - currently set to 256
 Block device 254:1

 --- Logical volume ---
 LV Path /dev/triagia/kaliswap
 LV Name kaliswap
 VG Name triagia
 LV UUID POkVXd-UMoe-yHaB-nfrV-lbpO-Fv3l-86N7AT
 LV Write Access read/write
 LV Creation host, time conDoin, 2015-08-21 17:54:32 +0200
 LV Status available
 # open 0
 LV Size 4.00 GiB
 Current LE 1024
 Segments 1
 Allocation inherit
 Read ahead sectors auto
 - currently set to 256
 Block device 254:2

After some extra-extra reading on the Arch forums I've added lvm2 to mkinitcpio.conf under HOOKS.

HOOKS="base udev autodetect modconf block keyboard keymap encrypt resume lvm2 filesystems fsck"

And then I ran again:

mkinitcpio -p linux
systemctl enable lvm2-lvmetad.service
grub-mkconfig -o /boot/grub/grub.cfg

But this didn't change anything.

Boot volume

drwxr-x---+ 4 root root 80 Aug 23 19:19 ..
drwxr-xr-x 4 root root 1024 Aug 21 18:18 .
-rw-r--r-- 1 root root 19692558 Aug 21 18:18 initrd.img-4.0.0-kali1-amd64
drwxr-xr-x 2 root root 1024 Aug 21 18:14 grub
drwx------ 2 root root 12288 Aug 21 18:00 lost+found
-rw-r--r-- 1 root root 165968 Jun 3 10:08 config-4.0.0-kali1-amd64
-rw-r--r-- 1 root root 2790804 Jun 3 10:08 System.map-4.0.0-kali1-amd64
-rw-r--r-- 1 root root 3274048 Jun 3 10:07 vmlinuz-4.0.0-kali1-amd64

grub dir:

drwxr-xr-x 4 root root 1024 Aug 21 18:18 ..
drwxr-xr-x 2 root root 1024 Aug 21 18:14 .
-rw-r--r-- 1 root root 2400500 Aug 21 18:14 unicode.pf2

I've created a manual Grub config in 40_custom and this almost works. The LVM is found and luks on root is decrypted but then I get this error:

Begin: Running /scripts/init-bottom ... mount: mounting /dev on /root/dev failed: No such file or directory
done.
No init found. Try passing init= bootarg.

Then I'm left with command line: (initramfs) _

Manual GRUB config:

menuentry 'Kali' 
insmod lvm
insmod gzio
insmod part_msdos
insmod ext2
set root=lvm/triagia-kaliboot
search --no-floppy --fs-uuid --set=root f1eb6904-c17e-40b7-8740-60e67b8d04de
linux /vmlinuz-4.0.0-kali1-amd64 root=/dev/mapper/triagia-kaliboot setkmap=us
initrd /initrd.img-4.0.0-kali1-amd64

You will need to add the kernel parameter in order for GRUB to decrypt the disk so that it can load your kernel.

Add command below into GRUB's kernel parameter:

cryptdevice=UUID=device-UUID:lvm root=/dev/mapper/MyVol-root
The <device-UUID> refers to the UUID of /dev/sdaX

Decrypt and then boot, that's it.
For more information, please refer to Arch Wiki.