Bug 12196

Summary:	kernel update results in device.map and menu.lst being wrongly re-written
Product:	Mageia	Reporter:	James Kerr <jim>
Component:	RPM Packages	Assignee:	Mageia Bug Squad <bugsquad>
Status:	RESOLVED OLD	QA Contact:
Severity:	normal
Priority:	Normal	CC:	nic, warrendiogenese
Version:	Cauldron
Target Milestone:	---
Hardware:	x86_64
OS:	Linux
Whiteboard:
Source RPM:		CVE:
Status comment:

Description James Kerr 2014-01-04 15:29:49 CET

I have two sata disks, which are seen by Mageia as sda and sdb
sdb is set in the BIOS as the boot device

I have Mageia 3 on sdb1, with Grub in the MBR of sdb.
device.map is
(hd0) /dev/sdb
(hd1) /dev/sda
and it is not changed when the kernel is updated


I have cauldron on sdb9, with Grub in the root partition, sdb9
When the kernel is updated, device map is re-written as
(hd0) /dev/sda
(hd1) /dev/sdb
and menu.lst is changed to refer to hd1,8 as the root partition
If I then use the GUI to "set up the boot system" (drakboot --boot), the boot device is explicitly asked for and can be re-set to sdb.
Both device.map and menu.lst are then corrected.




Reproducible: 

Steps to Reproduce:

Comment 1 William Murphy 2014-01-14 23:23:03 CET

It's a known bug with grub.
When grub creates the device map, it's guessing as mentioned in the grub info:

  "The reason why the grub shell gives you the device map file is that
   it cannot guess the map between BIOS drives and OS devices correctly in
   some environments."

It gets it wrong sometimes, depending on the machine, OS or OS release. If it gets it wrong once, it will get it wrong with every kernel update. 

My advice it to make a copy of the working device.map and menu.lst and try to remember to copy them back after a kernel update (before rebooting).

CC: (none) => warrendiogenese

Comment 2 Nic Baxter 2015-12-24 06:35:02 CET

I may be off track here but why do you need grub installed in the root partition when it is in the MBR? Shouldn't one grub installation be able to boot two distribution?

Nic

CC: (none) => nic

Comment 3 James Kerr 2015-12-24 10:57:04 CET

I "solved" this problem some time ago by installing a drive tray and using only one drive at a time. Each drive is always booted as sda. I am, therefore, unable to do any further testing. I've closed the bug as "old".

Resolution: (none) => OLD
Status: NEW => RESOLVED