Arch Linux

JoeHartley

Member

Registered: 2011-10-01

Posts: 23

Another "unable to find root device" problem, with a twist!

My mom has a Dell latitude E6510 laptop that I set up with Arch, and she's very happy with it.  It recently developed an issue where it would not power on, so I dropped her drive into an identical model (I had a couple of them that I acquired when a company closed its doors).  It booted, all looked well, and I decided to do a pacman -Syu as it had been a couple of months since I'd run it last there.

I ran into the problem documented in other threads where I get the SysLinux menu, choose the usual Arch option, and get the following:

  Decompressing Linux... Parsing ELF... done.
  Booting the kernel.
  ::  Starting udevd...
  done.
  Waiting 10 seconds for device /dev/sda3 ...
  ERROR: device '/dev/sda3' not found. skipping fsck.
  ERROR: Unable to find root device '/dev/sda3'.
  You are being dropped to a recovery shell
          type 'exit' to try and continue booting
  sh: can't access tty; job control turned off

So it looked from research that I just needed to do a mkinitcpio, which I did by:
- booting from a USB thumbdrive
- mount -t ext4 /dev/sdb3 /mnt
- mount -t ext4 /dev/sdb1 /mnt/boot
- arch-chroot /mnt /bin/bash
- mkinitcpio -p linux
- exit
- reboot

And hey presto - it worked!  Except that the next time I booted the machine, I was back to "ERROR: Unable to find root device '/dev/sda3'."

Lather, rinse, repeat ad nauseum.  I did this 3 times with the same results: I can only boot the system once before I have to do another mkinitcpio which will work once.

For now, I've given her instructions to leave the machine on, and left the flash drive there in case I have to walk her through a restart, which won't be a lot of fun.

Does anyone know what's going on in this situation?

Thanks!

jasonwryan

Anarchist

From: .nz

Registered: 2009-05-09

Posts: 30,424

Website

Re: Another "unable to find root device" problem, with a twist!

Use persistent naming...

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Arch + dwm   •   Mercurial repos  •   Surfraw

Registered Linux User #482438

JoeHartley

Member

Registered: 2011-10-01

Posts: 23

Re: Another "unable to find root device" problem, with a twist!

Use persistent naming...

Is this an issue with only one device in the system?

In my example above, the USB flash drive is set as sda and the SSD was seen as sdb, hence the mounts, but without the USB drive connected, there's only the one drive.  The /etc/fstab file was generated with "genfstab -U /mnt >> /mnt/etc/fstab" which I though would use UUIDs but I'll check on that when I get a chance.

Thanks.