mount: unknown filesystem type ‘LVM2_member’

thoth · 2013-07-02 22:55:03

I recently did a pacman -Syu with some consequences. I still had grub1 running and it was automatically upgraded to grub2, which is fine, but apparently grub-install was run on the mbr (I really think that was very inappropriate as that did break my system). Anyhow, on to chroot, I update /etc/default/grub as I have an LVM on top of an encrypted root and add this:

GRUB_CMDLINE_LINUX="cryptdevice=/dev/sda5:VGarch"

and this to mkinitcpio.conf:

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

then update both:

mkinitcpio -p linux
grub-mkconfig -o /boot/grub/grub.conf

and then update again for good measure while we're still in the chroot. However, upon reboot I get the ominous error message:

mount: unknown filesystem type ‘LVM2_member’

EDIT: i moved fsck behind filesystems in hooks with no effect

Last edited by thoth (2013-07-03 01:31:06)

fruitC · 2013-07-03 11:45:32

have you loaded the dm-mod kernel module?
MODULES="ext4 dm_crypt dm-mod"

thoth · 2013-07-03 13:05:24

it drops me to a shell after it throws the unknown filesystem error, at that point lsmod does show dm-mod, and /dev/mapper has my lvm in it. I'm writing this from another system that also is an lvm on top of encrypted partition (this one never had grub1 on it though). The kernels are the same:

uname -r
3.9.8-1-ARCH

so I'm fairly certain this kernel has lvm2 support, and I've ran "pacman -S lvm2" with no help (lvm2 was already installed).

Last edited by thoth (2013-07-03 13:05:59)

cfr · 2013-07-07 23:26:44

Post the entire kernel command line you are using (/proc/cmdline).

Note that the upgrade to grub2 will not have automatically installed grub to disk. So if you have not installed grub to disk, you need to do that in order to configure it correctly.

i.e. grub-install was *not* run on the mbr as part of the package upgrade.

See /var/lib/pacman/local/grub-2.00.5043-2/install.

But your config file for the old grub will have been moved to a .pacsave when that package was removed by pacman.

Last edited by cfr (2013-07-07 23:28:53)

thoth · 2013-07-08 00:19:03

I certainly re-installed grub to disk, and I am fairly certain something in the arch upgrade process messed with mbr as I had the mbr pointed to another linux distro that was chainloading the arch grub. And after rebooting the arch boot partition was pointed to by mbr and not my other boot partition. Yes yes it sounds like I had quite a complicat ed setup going on, and after 3 years I've decided to reformat the disk, paman -Qq>paclist and back up home. All good now, but no clue as to what happened to the other install.

cfr · 2013-07-08 00:53:46

Well you can see what the install script does.

Plus lots of people have been on the boards precisely because the update did *not* install grub to disk... and neither did they.

Arch Linux

#1 2013-07-02 22:55:03

mount: unknown filesystem type ‘LVM2_member’

#2 2013-07-03 11:45:32

Re: mount: unknown filesystem type ‘LVM2_member’

#3 2013-07-03 13:05:24

Re: mount: unknown filesystem type ‘LVM2_member’

#4 2013-07-07 23:26:44

Re: mount: unknown filesystem type ‘LVM2_member’

#5 2013-07-08 00:19:03

Re: mount: unknown filesystem type ‘LVM2_member’

#6 2013-07-08 00:53:46

Re: mount: unknown filesystem type ‘LVM2_member’

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