Arch Linux

ottoshmidt

Member

From: Tbilisi, Georgia

Registered: 2010-04-03

Posts: 30

Can't mount dual boot Arch installed on LVM partition

I am trying to have Arch alongside Fedora installation.

Here's my lsblck output (on Fedora):

NAME                          MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda                             8:0    0 465.8G  0 disk
├─sda1                          8:1    0   200M  0 part /boot/efi
├─sda2                          8:2    0   500M  0 part /boot
├─sda3                          8:3    0 147.3G  0 part
│ ├─fedora_pc--200--43-swap   253:2    0   800M  0 lvm  [SWAP]
│ └─fedora_pc--200--43-root   253:3    0 146.5G  0 lvm
└─sda4                          8:4    0 317.8G  0 part
  ├─fedora_pc--200--4300-root 253:0    0    50G  0 lvm  /
  ├─fedora_pc--200--4300-swap 253:1    0   3.9G  0 lvm  [SWAP]
  └─fedora_pc--200--4300-home 253:4    0 263.9G  0 lvm  /home
sr0                            11:0    1  1024M  0 rom

I mounted /dev/fedora_pc--200--43/root on my /mnt and installed Arch from my working Fedora with bootstrap method (here).

/dev/fedora_pc--200--43/root is really a symbolic link to /dev/dm-3

Then I ran this to regenerate grub:

grub2-mkconfig -o /boot/efi/EFI/fedora/grub.cfg

The entry is added to grub menu, but when trying to boot Arch I get /dev/dm-3 not found error. When I run ls in rescue shell, there are no /dev/dm-1(,2,3,4 ) only /dev/sda1(2,3,4). If I run:

mount /dev/sda3 /

I get:

mount: unknown filesystem type 'LVM2_member'

I haven't actively dealt with LVM volumes before. Any help would be appreciable.

Last edited by ottoshmidt (2015-10-27 17:22:38)

Lone_Wolf

Administrator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 13,354

Re: Can't mount dual boot Arch installed on LVM partition

Do you have the lvm2 hook in arch /et/cmkinitcpio.conf ?

If you do, you may have to change the path to root-device in grub.cfg , check "Kernel options" section of  arch wiki on LVM.

---

Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

clean chroot building not flexible enough ?
Try clean chroot manager by graysky

ottoshmidt

Member

From: Tbilisi, Georgia

Registered: 2010-04-03

Posts: 30

Re: Can't mount dual boot Arch installed on LVM partition

I have this line in /etc/mkinitcpio.conf in Arch:

HOOKS="base udev autodetect modconf block filesystems keyboard fsck"

I don't see any lvm2

Lone_Wolf

Administrator

From: Netherlands, Europe

Registered: 2005-10-04

Posts: 13,354

Re: Can't mount dual boot Arch installed on LVM partition

chroot into the arch environment

run lvscan , it should list your lvm volumes.
verify if those are also present under /dev/mapper/ .
If no volumes are shown :

# vgscan
# vgchange -ay

Verify which entry in /dev/mapper/ corresponds with arch  /  .
use that entry in FC grub config as root= paramater for your arch boot line .

Now edit /etc/mkinitcpio.conf and put the lvm2 hook between block and filesystems so the hooks line looks like this :

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

Verify arch /boot is mounted correctly, then run mkinitcpio -p linux to update your initramfs .

exit the chroot, reboot into arch.

Last edited by Lone_Wolf (2015-10-29 11:57:33)

---

Disliking systemd intensely, but not satisfied with alternatives so focusing on taming systemd.

clean chroot building not flexible enough ?
Try clean chroot manager by graysky