Grub Issue - Page 2

mathguy · #16 28th November 2008, 03:46 PM

Quote:

Originally Posted by aabate58

Do you actually have scsi/sata devices? If they're IDE, you'll want to use /dev/hda.
Sorry if that comes off as a stupid question, but sometimes it's the little things.

Thanks for the response, LenL. Yes, I have scsi devices. I had tried using /sbin/grub-install /dev/hda to see if that made any difference to anything (no).

aabate58 · #17 28th November 2008, 04:01 PM

Quote:

Originally Posted by mathguy

Thanks for the response, LenL. Yes, I have scsi devices. I had tried using /sbin/grub-install /dev/hda to see if that made any difference to anything (no).

Give this a shot....

grub-install --recheck /dev/sda

nyjetshead · #18 28th November 2008, 04:08 PM

From the recover console after you mounted /sysimage
If you are sure your booting from /sda, (verify using fdisk -l)

At the grub prompt:
Verify that grub can find your /boot/grub directory by using find.

find /grub/stage1 (This verifys that grub can find your installation, you should receive a response (hd0,0) )

root (hd0,0)

setup (this puts grub on the MBR of /sda)

You will get a message from grub stating what it installed.

Reboot.

Optional: If you want to see the grub menu edit /grub/grub.config comment out
the hiddenmenu command.

If you get to the menu you know grub is working.

deepakmahajan · #19 28th November 2008, 04:09 PM

Hi Mathguy,

I got back my Grub with Super Grub Boot ISO. http://forjamari.linex.org/frs/?grou...release_id=499

Downloaded Super Grub, burned on CD, booted with the CD and Woh, I got my grub entries with it.

Currently it is going to boot Fedora 10, wish luck.

Thanks guy's.

mathguy · #20 28th November 2008, 04:18 PM

Quote:

Originally Posted by aabate58

Give this a shot....

grub-install --recheck /dev/sda

Thanks, aabate58. I tried this and get the message:

Probing devices to guess BIOS drives. This may take a long time.
No suitable drive was found in the generated device map.
Reverting to backed up copy.

I checked /boot/grub/device.map and it contains

# this device map was generated by anaconda
(hd0) /dev/sda
(hd1) /dev/sdb

which is as expected (my Dell C840 Latitude has two hard drives). Further ideas are welcome!

mathguy · #21 28th November 2008, 04:49 PM

Hi nyjetshead, thanks. I tried the above and a little more:

Quote:

Originally Posted by nyjetshead

From the recover console after you mounted /sysimage
If you are sure your booting from /sda, (verify using fdisk -l)

Running fdisk -l gives me

"Cannot open /proc/partitions"

and a cd to /proc/partitions shows its empty, while running fdisk /dev/sda and fdisk /dev/sdb returns

"Unable to open /dev/sda"
"Unable to open /dev/sdb"

Quote:

Originally Posted by nyjetshead

At the grub prompt:
Verify that grub can find your /boot/grub directory by using find.

find /grub/stage1 (This verifys that grub can find your installation, you should receive a response (hd0,0) )

In response to find /boot/grub/stage1, I just got

/boot/grub/stage1

echoed back to me.

Quote:

Originally Posted by nyjetshead

root (hd0,0)

You mean this as a command or response to find find /boot/grub/stage1? I get a syntax error (if you meant a command).

Quote:

Originally Posted by nyjetshead

setup (this puts grub on the MBR of /sda)

You will get a message from grub stating what it installed.

Hmmm. I get a graphical display menu (Firewall Configuration, etc, with a few other options), but nothing about writing (or failing to write) to the MBR. I'll be happy when I get to the bottom of this! Thanks for the ideas ...

nyjetshead · #22 28th November 2008, 05:03 PM

Responses are similar to when you don't have root permissions, are you logged in as root?
Also to be clear the commands given are used after you have started grub IE the grub prompt grub>

aabate58 · #23 28th November 2008, 05:15 PM

Quote:

Originally Posted by mathguy

Thanks, aabate58. I tried this and get the message:

Probing devices to guess BIOS drives. This may take a long time.
No suitable drive was found in the generated device map.
Reverting to backed up copy.

I checked /boot/grub/device.map and it contains

# this device map was generated by anaconda
(hd0) /dev/sda
(hd1) /dev/sdb

which is as expected (my Dell C840 Latitude has two hard drives). Further ideas are welcome!

Hmm, you mentioned that you have SCSI drives (not SATA), so I think those lines should read:
(sd0) /dev/sda
(sd1) /dev/sdb

-Al

mathguy · #24 28th November 2008, 05:59 PM

Quote:

Originally Posted by nyjetshead

Responses are similar to when you don't have root permissions, are you logged in as root?
Also to be clear the commands given are used after you have started grub IE the grub prompt grub>

Yes, I'm logged in as root. However, I had forgotten to go to the grub> prompt -- sorry! (Too much to eat and drink yesterday.) However, when at the grub> prompt, running

find /boot/grub/stage1

just gives "File not found", though the file exists. Also at the grub> prompt, running

root (hd0,0)

gives "Selected disk does not exist", while running

setup

gives "Unrecognized device string".

To recap, F10 installed as an upgrade from F9 and booted into F10 with no problem. I only encountered the chaotic grub boot display after I'd ran a system update and then rebooted. Further thoughts welcome ...

mathguy · #25 28th November 2008, 06:02 PM

Quote:

Originally Posted by aabate58

Hmm, you mentioned that you have SCSI drives (not SATA), so I think those lines should read:
(sd0) /dev/sda
(sd1) /dev/sdb

-Al

Thanks for pointing that out. However, in F9 the disks were labeled hd0 and hd1 in grub.conf and that never caused a problem, though fdisk shows the corresponding devices as /dev/sda and /dev/sdb. If this is an F9 -> F10 discontinuity, are you suggesting I just edit grub.conf and re-running grub-install?

jim1944 · #26 28th November 2008, 06:44 PM

Quote:

Originally Posted by aabate58

Do you actually have scsi/sata devices? If they're IDE, you'll want to use /dev/hda.
Sorry if that comes off as a stupid question, but sometimes it's the little things.

Fedora 10 designates even IDE drives as /dev/sda. I think they did away with /dev/hd* in F7 (give or take a release or 2).

Jim

miltbos · #27 28th November 2008, 07:47 PM

Read through the entire thread to this point, tried everything suggested and more.

Have been trying unsuccessfully to get grub to boot. Can't get a response to the "find /boot/grub/stage1" command in grub - gives an "Error 15: File not found." but I can change to the directory and see the stage1 file existing there.

See a very odd device name when I do a blkid to see which UUID the boot device is. The UUID of the device in the grub.conf has a "/dev/dm-0" descriptor instead of a "/dev/sd__" descriptor like the rest of my drive partitions.

nyjetshead · #28 28th November 2008, 07:50 PM

Mathguy
After you mounted the sysimage (chroot /mnt/sysimage) can you see anything on the drive?

What do you get when you enter ls at the command line.
If you see the directory structure of the drive then the sscii driver are loaded and working.

nyjetshead · #29 28th November 2008, 07:53 PM

Miltbos
Try find /grub/stage1 as I stated before you don't need /boot

miltbos · #30 28th November 2008, 07:59 PM

Doesn't matter whether I look for "/grub/stage1" or "/boot/grub/stage1" - get same error message either way.

I can see all of the directories that should exist there and can move around in them to my heart's content when I boot from the from the rescue disk.

I can "vi" the grub.conf, and that is how I determined the odd device name of "/dev/dm-0" was associated with the boot sector, and not what I expected to see there.