[Bug 923070] Re: Cloning GRUB2/GRUB-legacy makes clone not bootable

[Francis Lamonde]

fstab still supports disk-ids, but I guess that's not part of grub, really, it's to mount the fs.
In grub.cfg and other grub files you are correct it has UUID. But let's put aside UUIDs for a moment, cuz that did not change anything for the blank screen.

I have tested all what you mentioned before opening the ticket.

Let me recap for easier reading:

How am I doing the copy?
Byte-per-byte.
At the interface level I use 2 different ways:

1- I use g4l bootable CD and image my root partition in RAW mode (http://sourceforge.net/projects/g4l/)
2- If I am inside the distro on one disk and the other disk's partition is unmounted, I use the following command:

sudo dd if=/dev/sdxy ibs=4096 conv=noerror | gzip -9 >
/img/filename.img.gz

Never had a problem with either ways, except now with Kubuntu 11.10
(never tested with older versions of *buntu).

Now if I clone my root partition (and I also clone the /tmp partition), remove the original disk and try to boot with only the cloned disk plugged in like you mention, I still get the blank screen instead of grub2's menu. That is my problem, actually and the reason why I opened this ticket.
I have tested these exact steps using grub-legacy as well and surprisingly I get the same result. Which complicated furthermore my troubleshooting and testing as now I have no idea what else to test.

So the cleanly installed Kubuntu with either grub2 or grub-legacy can
boot up no problem. I then initiate an image and restores the image to
another identical disk and whether that cloned disk is booted alone or
with the original disk as SATA1 (SATA0 being the cloned disk), I get the
same blank screen instead of grub's menu.

That is 4 different setups:

1- grub2, cloned disk as SATA0 and original as SATA1;
2- grub2, cloned disk alone as SATA0, original disk completely unplugged;
3- grub-legacy, cloned disk as SATA0 and original as SATA1;
4- grub-legacy, cloned disk alone as SATA0, original disk completely unplugged.

Result: exact same. Blank screen with top left blinking cursor and only
command working is CTRL-ALT-DEL.

Cloning is performed either of the following ways:

1- Using g4l bootable CD and image my root partition in RAW mode;
2- If I am inside the distro on one disk and the other disk's partition is unmounted, I use sudo dd if=/dev/sdxy ibs=4096 conv=noerror | gzip -9 > /img/filename.img.gz

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https://bugs.launchpad.net/bugs/923070

Title:
  Cloning GRUB2/GRUB-legacy makes clone not bootable

Status in “grub2” package in Ubuntu:
  Incomplete

Bug description:
  grub2 v1.99 included with Kubuntu 11.10.
  ALSO TESTED WITH
  grub-legacy part of Kubuntu 11.10 packages (Muon).

  
  I have 2 identical disks, the only difference being their manufacturer serial number (disk ID) or UUIDs if using them.

  Before trying Kubuntu I was (And still am due to this problem) with
  openSUSE.

  Both disks have the exact same partition table.
  Both disks run exactly the same with the same distro, same grub-legacy, same data on each.
  I can boot each disk in any order I want, whether they are both connected at the same time or any of them connected alone.
  I can swap the order of the disks and boot no problem.

  These disks are used in a testing and backup configuration and
  requirements, therefore I often make images of partitions and restores
  them, on any disk, as I wish. It always works, using 'dd' from inside
  the distro or 'g4l', the Ghost For Linux application on a bootable CD.

  
  My problem:
  With Kubuntu 11.10 I realized when I clone the disk or root partition, the cloned disk becomes UNBOOTABLE, not matter if I use grub2 or grub-legacy!
  Everything works fine on the disk I installed Kubuntu on. The one I clone does not boot/startup grub (grub2 or grub-legacy, I get the EXACT same behavior).

  
  Example:

  DISK1
  sda1 linux partition
  sda7 temp partition
  I have other partitions for DATA purposes only.
  The root and boot are in sda1.

  DISK2
  sdb1 linux partition
  sdb7 temp partition
  I have other partitions for DATA purposes only.
  The root and boot are in sdb1.

  With openSUSE I can clone sdb1, sda1, sdb7 and sda7 and restore the
  images to the other disk or the same disk and both disks remain
  bootable, no matter the order and no matter if one or both are
  connected at the same time. This is my requirement and openSUSE
  fulfills it.

  If I CLEAN install Kubuntu 11.10 on DISK2 connected alone (it becomes
  sda1), I can boot it no problem,

  The problem occurs if I clone sdb1 and sdb7 of DISK2 to sda1 and sda7
  on DISK1. Then DISK1 does not boot grub2 (or grub-legacy) menu no
  matter what. Alone, both disks, 1st or 2nd, problem is the same. I get
  a blank screen with a fast blinking cursor top left and only CTRL-ALT-
  DEL works. My DISK1, newly cloned BYTE PER BYTE including MBR and
  partition tables becomes totally unusable.

  This is an obvious show-stopper for me cuz the cloned disk is not
  bootable!

  But if I image sdb1 on DISK2 and restores it to sdb1 on DISK2, it
  works! On another disk, it doesn't. No matter if it's grub2 or grub-
  legacy!

  This problem is not existent with openSUSE using grub-legacy.

  
  What's the problem with Kubuntu 11.10?
  And how to fix it so that a simple clone will work (re-installing grub2 or grub-legacy after a clone is not an option, this defeats the purposes of my cloning requirements).

  Thank you

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