CentOS - Jul 2009 - Grub fallback problem

Hi !

I am running CentOS 5 using grub 0.97

Let's try this again :)

I am running CentOS 5 (core pkgs) / x86_64 using grub 0.97 and I am trying to
configure a fallback between two partitions on my local disk, each installed
with a CentOS image.   The idea is to be able to install a new test OS image and
fall back in case of a problem to the default image.  This is a great grub
feature !  Except it does not work for me :(

grub.conf:
#-----------------------------------------------
default saved
timeout=5
fallback 1

title NEW OS
  root (hd0,0)
  kernel /boot/vmlinuz-new root=/dev/sda1 panic=5
  initrd /boot/initrd-new.img
  savedefault fallback

title DEFAULT OS
  root (hd0,1)
  kernel /boot/vmlinuz-default root=/dev/sda2
  initrd /boot/initrd-default.img
  savedefault
#-----------------------------------------------

Grub is installed on /dev/sda1, but not on /dev/sda2.  /dev/sda1 is 
the primary boot partition.  Both partitions are formatted with ext3.

The problem is that the fallback does not work for me.  For instance, if I
specify on purpose a wrong root device with the NEW OS, e.g. root=/dev/sda3,
then the kernel panics and reboots properly after 5 sec.  However, grub then
attempts to boot the NEW OS all over again.  The same is true when I fully boot
NEW OS with the right root device and then panic the kernel on purpose.

Now, I have read somewhere that grub requires a default file to get
the savedefault feature working.  However, I could neither find the
'savedefault' command nor the grub default file under /boot/grub or
anywhere else.  One more thing, when I choose the boot title manually
then grub seems to remember my last choice.  In other words, grub is
preserving my last choice from a previous boot.

Am I doing something wrong ?  Do I need to install something in addition to grub
0.97 ?

Your help is much appreciated,
Matthias

--- On Wed, 7/29/09, Matthias Blankenhaus <matthiasblankenhaus at
yahoo.com> wrote:
> From: Matthias Blankenhaus <matthiasblankenhaus at yahoo.com>
> Subject: Grub fallback problem
> To: centos at centos.org
> Date: Wednesday, July 29, 2009, 11:19 AM
> Hi !
> 
> I am running CentOS 5 using grub 0.97? 
> 
> 
> ? ? ? 
>

Hi !

I am posting this again, since I still have the problem and have not
been able to resolve this.  Please, take a look and comment if you can.
Thank you !

I am running CentOS 5 (core pkgs) / x86_64 using grub 0.97 and I am trying to
configure a fallback between two partitions on my local disk, each installed
with a CentOS image.   The idea is to be able to install a new test OS image and
fall back in case of a problem to the default image.  This is a great grub
feature !  Except it does not work for me :(

grub.conf:
#-----------------------------------------------
default saved
timeout=5
fallback 1

title NEW OS
  root (hd0,0)
  kernel /boot/vmlinuz-new root=/dev/sda1 panic=5
  initrd /boot/initrd-new.img
  savedefault fallback

title DEFAULT OS
  root (hd0,1)
  kernel /boot/vmlinuz-default root=/dev/sda2
  initrd /boot/initrd-default.img
  savedefault
#-----------------------------------------------

Grub is installed on /dev/sda1, but not on /dev/sda2.  /dev/sda1 is
the primary boot partition.  Both partitions are formatted with ext3.

The problem is that the fallback does not work for me.  For instance, if I
specify on purpose a wrong root device with the NEW OS, e.g. root=/dev/sda3,
then the kernel panics and reboots properly after 5 sec.  However, grub then
attempts to boot the NEW OS all over again.  The same is true when I fully boot
NEW OS with the right root device and then panic the kernel on purpose.

Now, I have read somewhere that grub requires a default file to get
the savedefault feature working.  However, I could neither find the
'savedefault' command nor the grub default file under /boot/grub or
anywhere else.  One more thing, when I choose the boot title manually
then grub seems to remember my last choice.  In other words, grub is
preserving my last choice from a previous boot.

Am I doing something wrong ?  Do I need to install something in addition to grub
0.97 ?

I have done the RTFM / info thing.

Your help is much appreciated,
Matthias