GRUB Error (wrong 'root=' format)

SentralOrigin · 02-22-2007, 11:00 AM

I am on my last step to installing Gentoo, but I get a GRUB error when I try to boot:

Code:

VFS: Cannot open root device "hda3" or unknown-block(0,0)
Please append a correct "root=" boot option
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)

This is what my current /boot/grub/grub.conf looks like:

Code:

default 0
timeout 2
title=Linux
root (hd0,0)
kernel /boot/linux-2.6.17.13 root=/dev/hda3

Yes I made sure that was the correct kernel name in the correct directory. Partition 1 is my boot, 2 is my swap, and 3 is my root. I installed GRUB to partition 1 where the /boot is. I formatted corectly and everything. I did this before, and I remember getting this very same error, but I don't remember what I did to GRUB to fix it. I didn't make changes to anything else, I think.

reddazz · 02-22-2007, 11:30 AM

What device node are you using as your root partition? As it is you have set two different device nodes hd0,0 (which is hda1) and hda3.

SentralOrigin · 02-22-2007, 11:39 AM

This is my /etc/fstab:

Code:

/dev/hda1 /boot ext3 defaults,noatime 1 2
/dev/hda3 / ext3 noatime 0 1
/dev/hda2 none swap sw 0 0

So I guess hd0,0 is hda1
And hd0,2 is hda3

reddazz · 02-22-2007, 11:44 AM

Yes, hda3 is hd0,2.

Gethyn · 02-22-2007, 11:44 AM

Is there a symlink in /boot pointing to itself? I seem to remember that Gentoo puts it there by default, but if it's missing then the final line of your grub.conf is wrong.

Probably this is a stupid question, but it has to be asked: did you compile ext3 support into your kernel? (not as a module)

Also, there appears to be an error in the first line of your fstab as posted above: it should be ext3, not /ext3.

SentralOrigin · 02-22-2007, 11:45 AM

What settings should I change then?

Yes, in /boot there is a directory called /boot which goes back to itself.
Yes I compiled it with a *, not an M
Oh I typed it in wrong. There is no more / in the first line. Since I can't copy paste from another computer. Just a typo

SentralOrigin · 02-22-2007, 12:41 PM

/boot/grub/device.map

Code:

(fd0) /dev/fd0
(hd0) /dev/hda

aa085564 · 02-25-2007, 02:44 PM

I had the same issue on my system running FC5, however the problem manifested without
an upgrade attempt.

The problem ended up being a bad SDRAM module. I was running 2GB, 1024x2.

A memory test revealed sever errors on one of the modules. I removed it and the problem went away.

It may be worth running a memory test on your system. If you don't have a utility, the SUSE 10 boot cd or dvd has a built in memory tester.

Hope this helps.

CG

Quote:

Originally Posted by SentralOrigin

I am on my last step to installing Gentoo, but I get a GRUB error when I try to boot:

Code:

VFS: Cannot open root device "hda3" or unknown-block(0,0)
Please append a correct "root=" boot option
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)

This is what my current /boot/grub/grub.conf looks like:

Code:

default 0
timeout 2
title=Linux
root (hd0,0)
kernel /boot/linux-2.6.17.13 root=/dev/hda3

Yes I made sure that was the correct kernel name in the correct directory. Partition 1 is my boot, 2 is my swap, and 3 is my root. I installed GRUB to partition 1 where the /boot is. I formatted corectly and everything. I did this before, and I remember getting this very same error, but I don't remember what I did to GRUB to fix it. I didn't make changes to anything else, I think.

saikee · 02-25-2007, 03:00 PM

I am just curious as I don't use my Gentoo very much.

The menu.lst seem to miss out the ramdisk file, marked red below.

My Gentoo 2006.1 has the following entries in menu.lst

Code:

title Gentoo Linux
	root (hd1,39)
	kernel /boot/kernel-genkernel-x86-2.6.17-gentoo-r7 root=/dev/ram0 init=/linuxrc ramdisk=8192 real_root=/dev/hdc40
	initrd /boot/initramfs-genkernel-x86-2.6.17-gentoo-r7

dxqcanada · 02-25-2007, 03:11 PM

Make sure you are actually looking at your /boot partition.

By default the /boot partion is not auto mounted ... and must be manually mounted.

Run mount ... if you do not see /dev/hda1 then you are not viewing your real /boot directory.

Emerson · 02-25-2007, 03:19 PM

VFS: Cannot open root device "hda3" or unknown-block(0,0)

This error usually indicates kernel is unable to cope with your HDD controller. Missing SATA chipset driver, missing SCSI support.

Edit: I see now you have IDE, so it's missing IDE controller support.