Rescue and Recovery

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Rescue and Recovery

Rescue and Recovery version 3.0 consists of a bootable partition containing various system recovery tools, including full recovery of the preinstalled Windows XP partition. It can be activated by pressing the ThinkPad, Access IBM or ThinkVantage Button during system boot. It contains a FAT filesystem (labeled "IBM_SERVICE"), and has partition type 0x12 ("Compaq diagnostics" in fdisk).

As opposed to a Hidden Protected Area Recovery partitions are ordinary partitions, accessible through the partition table. As they are ordinary partitions they are accessible by ordinary partitioning tools. They should be dealt carefully with.

Proper MBR

ATTENTION!
Tinkering with the default MBR and the Rescue & Recovery partition puts risk to your system. It can result in rendering the system completely unusable and severe data loss. You follow any instructions described here on your own risk.

Consideration 6 of the Readme states:

"The Master Boot Record (MBR) must be configured properly for the Rescue and Recovery application to function properly. When possible, the Rescue and Recovery application attempts to ensure the proper configuration of the MBR. This can only occur if the Rescue and Recovery application is installed after other applications that requires the MBR."

Apparently, the MBR is not "configured properly" if LILO or GRUB has been installed in it as the following is the case:

  • the default MBR seems to ignore the active bit and always boots the first partition instead
  • the default MBR contains code to catch a press of the appropriate button during bootup and boot the R&R partition in that case
  • before booting the R&R, the default MBR changes it's partition type to 0x0b, otherwise it changes it to 0x12 (to hide it from Windows)
  • the R&R software assumes that the first partition contains Windows
  • the R&R partition needs to be of type 0x0b (FAT32) for the R&R software to work

Since neither LILO nor GRUB can catch the press of the button (an undocumented mechanism anyway) it is not possible to invoke Rescue and Recovery by pressing the appropriate button during system boot, once LILO or GRUB have altered the MBR for their boot procedure.

GRUB in the MBR

You can, however, boot the Rescue and Recovery partition from within a GRUB residing in your MBR. However if you leave its partitions type to 0x12 (Compaq disgnostics) this will result in an error message "c000021a, Fatal System Error" if you try to boot it. To avoid that and to make sure the recovery partition always is of the right type, add a line to change the partition type to 0x0b to the recovery partitions entry in your /boot/grub/menu.lst. Assuming your recovery partition is the second partition, it should look like this:

 title           IBM Rescue and Recovery
 root            (hd0,1)
 parttype        (hd0,1) 0x0b
 unhide          (hd0,1)
 chainloader     +1

We also add an unhide line here because we are going to hide the recovery partition on every boot of Windows, so we need to unhide it, when the recovery partition is booted. This is because if we wouldn't hide the partition when booting Windows, it would be visible and accessable there and that's not what we want. So, assuming that Windows is on the first partition, the Windows entry should now look like this:

 title           Windows
 root            (hd0,0)
 hide            (hd0,1)
 chainloader     +1

Now you should be able to boot the R&R partition from withing GRUB, residing in your MBR.

GRUB in a partitions boot sector

A way to have your Access IBM button still functional on bootup, is to create a separate /boot partition, install GRUB to that partition and make it active.

NOTE!
If the above finding is true that the MBR ignores the active bit, that partition has to be the first one.
  • In the BIOS, set the IBM Predesktop Area to 'Secure'.
  • Boot your Linux distributions installation CD.
  • Follow the instructions and go through the regular installation process.
  • Create a primary partition for /boot (the other stuff can go into the extended partitions) and when the time comes to install GRUB, make sure you install it into the boot sector of the boot partition.
  • Set this partition as active. Leave the MBR alone.

External Sources

Models featuring this technology