[SOLVED] Can't find LVM root device after pacman -Syu

DoctorWedgeworth · 2013-03-26 22:49:53

Hey, can anyone give me a hand here? I haven't updated in about a month, but the last time I did was definitely after the changes-to-lvm post in the news (I know that because it's what got me on the last update )

I noted just before the update that cat /proc/1/comm displayed "init", which surprised me. Maybe I'd installed systemd but not configured it?

Anyway now I'm getting:
Waiting 10 seconds for device /dev/mapper/belle-root …
ERROR: Unable to find root device '/dev/mapper/belle-root'
You are being dropped to a recovery shell.

I've chrooted from a SUSE CD I had lying around and followed the "changes to LVM" instructions again in case I'd missed something, but nothing is changing.

Can anyone help me out? Thanks.

Last edited by DoctorWedgeworth (2013-03-27 00:32:41)

WonderWoofy · 2013-03-26 22:53:58

Unless you installed your system after the move to systemd, you would have had to manually move to systemd. It was not automatic (and shouldn't be). Did you do this or not? I am assuming not, but there is also the possibility that you set things up and then never made it permanent with the systemd-sysvcompat package.

So after the boot is unable to find the root device, have you tried to continue by manually scanning for the VG and activating it?

DoctorWedgeworth · 2013-03-26 23:06:04

No I didn't do any configuration. Guess that explains my problem guessing this isn't going to be a quick fix then.

I tried continuing using the rescue shell but I couldn't find any lv* commands. I didn't check for pvscan/vgscan/vgchange.

While I've been messing I've somehow broken my USB keyboard, so it now won't work past grub. I tried changing the init=/usr/lib/systemd/systemd to init=/bin/bash (wishful thinking without a root device) but the same thing happened.

WonderWoofy · 2013-03-26 23:07:30

You have to use lvm first. As all those vg*, lv*, and pv* commands are actually links to the lvm command, you should have to do something like "lvm vgscan" instead of just "vgscan".

Edit: oh and at that point in the boot process, you are actually in the initramfs still (ash to be specific).

Edit2: I was having issues with a USB keyboard and a new machine (actually just a new bios), and found out that because of windows 8's requriement for a fast POST, the default is to turn off the scanning for usb devices. Though this was for UEFI, and I am not sure if the same would apply for a bios booting machine...

Last edited by WonderWoofy (2013-03-26 23:10:40)

DoctorWedgeworth · 2013-03-26 23:09:50

Any idea why my USB keyboard won't respond?

DoctorWedgeworth · 2013-03-26 23:47:52

I don't think it's BIOS because it's working in the grub menu, just not afterwards. It also works in a SUSE live CD. I installed systemd-sysvcompat but nothing changed. I've not emptied out rc.conf yet, I'm hoping I can do that with a more usable system. lvm2 is already added in mkinitcpio.conf between mdadm and filesystem.

DoctorWedgeworth · 2013-03-26 23:48:46

I've reset the BIOS to defaults anyway to make sure, and it made no difference.

jasonwryan · 2013-03-27 00:01:25

Please use the edit button rather than bumping your thread.

Do you have keyboard in your hooks? You should also be using the mdadm_udev hook.

DoctorWedgeworth · 2013-03-27 00:20:53

Sorry about the bump (although it was only a 55 second bump, the second was a response to an edit).

My hooks were: base udev autodetect block mdadm lvm2 filesystems keyboard
I've moved keyboard to after block (was this a bad move?) so now it's:
base udev block keyboard mdadm_udev lvm2 filesystems keyboard

And now it boots Thank you so much.

jasonwryan · 2013-03-27 00:24:02

Good to hear. Please remember to mark your thread as [Solved] by editing your first post and prepending it to the title.

Arch Linux

#1 2013-03-26 22:49:53

[SOLVED] Can't find LVM root device after pacman -Syu

#2 2013-03-26 22:53:58

Re: [SOLVED] Can't find LVM root device after pacman -Syu

#3 2013-03-26 23:06:04

Re: [SOLVED] Can't find LVM root device after pacman -Syu

#4 2013-03-26 23:07:30

Re: [SOLVED] Can't find LVM root device after pacman -Syu

#5 2013-03-26 23:09:50

Re: [SOLVED] Can't find LVM root device after pacman -Syu

#6 2013-03-26 23:47:52

Re: [SOLVED] Can't find LVM root device after pacman -Syu

#7 2013-03-26 23:48:46

Re: [SOLVED] Can't find LVM root device after pacman -Syu

#8 2013-03-27 00:01:25

Re: [SOLVED] Can't find LVM root device after pacman -Syu

#9 2013-03-27 00:20:53

Re: [SOLVED] Can't find LVM root device after pacman -Syu

#10 2013-03-27 00:24:02

Re: [SOLVED] Can't find LVM root device after pacman -Syu

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