[SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

elephantos · 2009-01-28 00:41:56

recently reinstalled arch, and after performing first -Syu the root device is not deteced. (/ = sda3)

Failed to parse block device name for /dev/disk/by-uuid/4f4[...]
ERROR: root fs cannot be detected.

$ echo /dev/*
does not show any disks, thus basic binary commands are not found

In Grub, tried the following to no avail:
-specifying root=/dev/sda3
-specifying rootfstype=ext3
-booting from fallback

booting into a live distro, i can mount the / partition as r/w. what should i do?

edit: the disk uuid is correct -i did ls-lF /dev/disk/by-uuid and that shows the same disks as fstab

edit: ive seen a few solutions saying to regenerate mkinitcpio. that would involve issuing "mkinitcpio" command, so how would one do that...

Last edited by elephantos (2009-01-28 02:04:45)

tim · 2009-01-28 01:11:46

same problem

mkinitcpio -p kernel26

Last edited by tim (2009-01-28 01:12:24)

elephantos · 2009-01-28 01:21:08

and from where should i run mkinitcpio ...? tried archlive, but i think that only pertains to the live image

tim · 2009-01-28 01:48:32

Sorry. Should have thought about it (and tried to fix the problem) before I posted.

I have no idea. I'm stuck as well.

Ranguvar · 2009-01-28 01:50:16

Boot the Arch live CD (or another CD), mount your root partition and all partitions under it, chroot into it, and then run mkinitcpio.

elephantos · 2009-01-28 02:04:20

o wow. thank you!

tim · 2009-01-28 02:30:24

This didn't change anything for me.

This is what I did (as per instructions of Ranguvar):

boot live cd
mount -rw -t ext3 /dev/sda1 /mnt
chroot /mnt
cd /boot
mkinitcpio
mkinitcpio -g kernel26.img

What am I doing wrong

elephantos · 2009-01-29 06:02:29

try:
chroot /mnt/sda3
mkinitcpio -p kernel26

and post what happens

tim · 2009-01-29 11:12:27

I gave up in the end.

I tried everything in every post on these forums that I found. I tried

mkinitcpio -p kernel26

as you suggested and I got exactly the same error on boot. Nothing changed.

I tried the suggestions in: http://bbs.archlinux.org/viewtopic.php?id=57150

i.e. mounting proc, sys, & dev and then

mkinitcpio -g /boot/kernel26.img -k 2.6.28-ARCH

and still nothing changed.

In the end I just installed again and everyting is fine. But the thing that doesn't make any sense to me is that I was installing from scratch when the problem happended in the first place. So why this happened the first time I installed and not the second is anyones guess. The one thing i did differently was to put mirror.aarnet.edu.au at the top of my mirror list the first time I installed and the second time I left the mirror list untouched.

Thanks anyway for your help.

blazercist · 2009-01-29 18:40:46

Same problem, seems the new kernel broke UUID.

@tim: as I stated above it seems that you fixed the problem with the kernel image file but did not adjust the grub menu to compensate for the fact that UUID is broken and thats why you got the same result even after fixing the image, lucky for me I had some broken hooks and only my fallback image generated properly so I figured it out, although it took me a little while.

Anyhow this is basically what needs to be done to correct the problem.

1. Boot ArchLive
2. mkdir /media/disk
3. mount /dev/sdxX /media/disk
4. chroot /media/disk
5. mkinitcpio -k 2.6.28-ARCH -g /boot/kernel26.img
6. nano /boot/grub/menu.lst
7. Replace any references to UUID with /dev/sdxX (where xX represents your drive and partition) instead, save and exit nano.
8. reboot

Make sure and pay attention to the output of the mkinitcpio command in my step 5. If there are any errors relating to one or more of the hooks you'll need to edit /etc/mkinitcpio.conf and remove the hook it complains about !!IF POSSIBLE!!. I for example had some problem with the autodetect hook which caused my regular kernel to fail to create an image.

If mkinicpio doesn't complain and tells you it SUCCEEDED generating the images then you should be good to go.

Last edited by blazercist (2009-01-29 18:47:25)

tim · 2009-01-30 01:04:04

@blazercist definitely sounds plausable. I did try changing references to /dev/sda1 in grub but because all that happened was my error message changed from not being able to parse the device name: UUID to not being able to parse the device name: /dev/sda1 I just reverted back to the UUID. I can't remember if I did that after specifying the kernel version with the -k option or before so perhaps I did this before and thats; as you say, why it failed. The other interesting thing is that I also had error messages for autodetect when running mkinitcpio but it said it succeded anyway and definitely generated an imge because I always renamed the previous one beforehand, rather than just overwritting it, specifically so I knew it had created a new one.

Either way, hopefully you've found that extra step that needed to be specified to fix this problem i.e. using references to /dev/sdaX instead of the UUID's.

eNTi · 2009-02-06 09:34:53

i do not use UUID in menu.lst but /dev/sda3 and i get exactly the same error, i'll try to mkinitcpio -k 2.6.28-ARCH -g /boot/kernel26.img. such errors are a real killer, even as a somewhat seasoned admin. that's even unacceptable for a free operating system, because it makes me wanna go back to windows again.

leeyee · 2009-02-06 11:37:23

I remember an odd problem I encountered before. The fresh installation of Arch would recognize my root partition as /dev/sda3 in menu.lst, but actually it's /dev/sda2, manually edit it solved the problem.

I know it's not the same here, but it reminds us what we need to improve.

sand_man · 2009-02-06 12:25:26

I can confirm that blazercist's procedure works.

tim · 2009-02-06 12:33:24

So here is what I don't get. If UUID is broken, then how come when I installed the second time (24 hours later) everything works just fine and dandy with UUID?

Arch Linux

#1 2009-01-28 00:41:56

[SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#2 2009-01-28 01:11:46

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#3 2009-01-28 01:21:08

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#4 2009-01-28 01:48:32

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#5 2009-01-28 01:50:16

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#6 2009-01-28 02:04:20

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#7 2009-01-28 02:30:24

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#8 2009-01-29 06:02:29

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#9 2009-01-29 11:12:27

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#10 2009-01-29 18:40:46

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#11 2009-01-30 01:04:04

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#12 2009-02-06 09:34:53

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#13 2009-02-06 11:37:23

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#14 2009-02-06 12:25:26

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

#15 2009-02-06 12:33:24

Re: [SOLVED]root fs cannot be detected for /dev/disk/by-uuid/.. after -Syu

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