11.3 grub and disk ordering/numbering

[Vahe Avedissian]

Greetings all,

My fstab, devices.map, and menu.lst all reference devices by I'd so that addind or removing disks should not affect grub
And booting.

This does not work for me with 11.3 and I get a grub error (11 or 17 or 22 - I forget) whenever I add or remove a drive. This worked perfectly with 11.2! Did this change with 11.3 and am I forgetting something here?

Any idea why this is not workin?

Thanks,

Vahe

[Markus Koßmann]

Hi Philipp,
Thank you for your reply. I am attaching a SATA drive to the motherboard
which obviously shifts raw device naming as seen by grub.
With the system as is, obviously everything works fine. When I add a new
SATA device
to the motherboard, I am getting grub error 17.
(hd0)
/dev/disk/by-id/ata-WDC_WD740ADFD-00NLR1_WD-WMANS1505822
(hd4)
/dev/disk/by-id/ata-INTEL_SSDSA2M080G2GN_CVPO9391018S080BGN
(hd3)
/dev/disk/by-id/ata-WDC_WD20EARS-00MVWB0_WD-WMAZ20081724
(hd1)
/dev/disk/by-id/ata-WDC_WD7500AAKS-00RBA0_WD-WCAPT0601614
(hd2) /dev/disk/by-id/ata-WDC_WD20EADS-00R6B0_WD-WCAVY0250778
###Don't change this comment - YaST2 identifier: Original name: linux###
title Desktop -- openSUSE 11.3 - 2.6.34.7-0.5
root (hd4,2)
kernel /vmlinuz-2.6.34.7-0.5-desktop
root=/dev/disk/by-id/ata-INTEL_SSDSA2M080G2GN_CVPO9391018S080BGN-part2
resume=/dev/disk/by-id/ata-WDC_WD740ADFD-00NLR1_WD-WMANS1505822-part2
splash=silent quiet showopts
vga=0x346
initrd /initrd-2.6.34.7-0.5-desktop
/dev/disk/by-id/ata-INTEL_SSDSA2M080G2GN_CVPO9391018S080BGN-part2 /
reiserfs acl,user_xattr 1
1
/dev/disk/by-id/ata-INTEL_SSDSA2M080G2GN_CVPO9391018S080BGN-part3 /boot
reiserfs acl,user_xattr 1
2
I did not have this problem with 11.2 and 11.1 and seems new with 11.3.
Any ideas what I am missing?

This error happens even before the kernel is loaded. So the /dev/disk/by-id
thing doesn't help. This is done by udev,when the kernel is allready running.

At system startup the BIOS does an enumeration of the available disks. Your
Intel becomes 5th BIOS disk (hd4) without attaching the addtional SATA disk.
After adding the additional drive it probably becomes 6th BIOS disk. As Grub
uses the BIOS to access the drives and doesn't know of that change you can
imagine, that something goes wrong now.

As first try I would try to move the SATA cable for the INTEL_SSDSA2M080G2GN
into the SATA port which you did use before for the 6th disk. If that
configation boots, attaching the 6th disk, using the SATA connector which was
used before by the SSD, should work too.

If that doesn't boot ,please have look into the BIOS boot messages to get an
idea , in which order the drives are recognized actually. You might have to
disable a BIOS splashscreen in your BIOS setup to see these messages.

But be aware, that booting from the 5th BIOS disk is allways a little bit
fragile. It will break again, if you remove one of the 4 disks, which are
enumerated before.

PS: And of course this is not a 11.3 problem. You probably just hadn't have a
drive configuration, which is able to trigger that problem before adding the
SSD with 11.3

[Cristian Rodríguez]

Post by Vahe Avedissian
Greetings all,
My fstab, devices.map, and menu.lst all reference devices by I'd so that addind or removing disks should not affect grub
And booting.
This does not work for me with 11.3 and I get a grub error (11 or 17 or 22 - I forget) whenever I add or remove a drive. This worked perfectly with 11.2! Did this change with 11.3 and am I forgetting something here?
Any idea why this is not workin?

I had your same issue, Grub messes stuff around , happended when I added
an Intel SSD 80Gb to this box.

I assume udev is messing stuff up, and that there is no warranty disks
will appear in the same order..

[Felix Miata]

Post by Cristian Rodríguez
Grub messes stuff around

It's not grub but the BIOS that messes things up and enumerates
differently

UUID & LABEL get the kernel/OS around this, but Grub 1 can't deal with it.

Post by Cristian Rodríguez
I assume udev is messing stuff up, and that there is no warranty disks
will appear in the same order..

Nobody is messing things up. It's just that in the world of dynamic
devices and device handling device enumeration isn't really
predictable.

It's really not much problem, IF you can:

1-boot with any USB storage devices attached only if you intend to actually
boot from such device on that boot

2-stick to using either PATA or SATA exclusively for HDs

OTOH, changing the PATA/SATA mix, or replacing a PATA or SATA HD, after
installing to either or both not unusually produces devastation. This is what
the recent Stan G "Unsuccessful installation of operating system" &
"BIOS/GRUB Problem" & Bob S "Basic 11.3 questions" threads were all about.
This is not to say I have no experience with the problem, as we got Bob S's
figured out by having him bring it here, and I guided Stan G to solution via
email conversation extending over several weeks.

This doesn't happen to my many systems because I don't mix SATA & PATA, and
have not one single bootable USB storage device. On most, I find a single HD
perfectly adequate for 3, 5 or 10 or more installed operating systems,
backing up across the network, or to temporarily attached USB or eSATA
storage devices.

It looks to me like those who need a PATA/SATA/USB mix need to explore Grub
"2", which may actually reach v2 GA in less than another year.
--
"The wise are known for their understanding, and pleasant
words are persuasive." Proverbs 16:21 (New Living Translation)

Team OS/2 ** Reg. Linux User #211409

Felix Miata *** http://fm.no-ip.com/