VFS: cannot open root device "2103" or [solved]

thinking · n00b Joined: 22 May 2005 Posts: 46

hiho@ll

i tried to install Gentoo 2005.0 using LiveCD:
System:
1400Mhz Athlon Thunderbird
Mainboard: KG7RAID
2 Harddisks (/dev/hde,/dev/hdg)
1 cdr (/dev/hda)
bootloader: LILO

partitions:
/dev/hdg - one ext3 partition (not really used yet)
/dev/hde - /dev/hde1 boot(ext2) 32M
/dev/hde2 swap 1024M
/dev/hde3 ext3 about 39Gb

during boot i get the following error message:
VFS: cannot open root device "2103" or unkown-block(33,3)
Please append a correct "root=" boot option
kernel panic - not syncing: VFS: Unable to mount root fs on unkown-block(33,3)
<7>ieee1394: Host added: ID:BUS[0-00:1023] GUID[0011060001169031]

---------------------

i know there are some posts about this problem (discussing SATA, boot loaders ...)
well, i don't have a solution yet

btw: i tried to install grub, but when the grub bootloader should load the screen gets black and my system restarts
so i switched to lilo, cause it works to boot, but i get the above error msg
everything else is default standard (gentoo handbook) configuration

question 1: What can cause the problem?
I mean, what possible facts can there be to force the kernel to show such a message?
question 2: well, anyone has an idea?

thx@ll

RayDude

kommissar · Tux's lil' helper Joined: 19 May 2005 Posts: 78

RayDude

thinking · n00b Joined: 22 May 2005 Posts: 46

@RayDude

i'm at work now, so i can't surely tell you my fstab, but as i said, i installed it like described in the handbook

so i think ext3 is set in fstab for /

but i'll have a look ;-)

thx

@kommisar
1:
well as already said, i used the handbook
this means my grub.conf looks like that from the handbook
WITH the timeout set
but with grub i get a black screen and the system restarts (not really waiting 30 seconds!)

that's why i don't want to use grub
lilo can boot, but i get an error
grub can't boot and i get nothing ;-)

2:
i don't know what you mean with "Your system has to have some form of bootloader"
because i posted that i'm using lilo
and i'm not sure, but i can only get the kernel panic, if the kernel boots
which means, lilo can load and boot the kernel, but the kernel fails

i'm not an expert, but doesn't this mean, it's a kernel problem, not a bootloader problem
well, i can use the root option using the bootloader, but it's the kernel who causes the problem
because the bootloader can load and start the kernel

or i'm thinking in the wrong direction?
*confused* *g*

hmm
another question:
why the error message looks like "kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(33,3)"?
i mean, why 33,3?
i think 3 = /dev/hde3
33 = /dev/hde?

why it's 33?

thx

nixnut · Posted: Wed May 25, 2005 4:57 pm Post subject:

RayDude · Posted: Wed May 25, 2005 5:40 pm Post subject:

thinking · n00b Joined: 22 May 2005 Posts: 46

lilo.conf

lba32
boot=/dev(hde
map=/boot/.map

install=/boot/boot-menu.b
menu-scheme=Wb
prompt
delay=50
vga=normal
image=/boot/kernel-2.6.11
root=/dev/hde3
label=Gentoo

grub.conf

default 0
timeout 30
splashimage=(hd0,0)/grub/splash.xpm.gz
title=Gentoo Linux 2.6.11-r3
root (hd0,3)
kernel /kernel-2.6.11 root=/dev/hde3
savedefault
boot

-------------------

i already tried everything posted in this thread
http://kerneltrap.org/node/970

summary:
using mkinitrd to generate an img
changed in lilo.conf
initrd=/boot/initrd-2.6.11.img

(i also changed it in the grub.conf but grub don't want to boot (i think grub-install can't install grub into my MBR, that's why i get a black screen and immediately reboot the system))

using the initrd in lilo.conf
i get the following error:
VFS: cannot open root device "2103" or unkown-block(33,3)
Please append a correct "root=" boot option
kernel panic - not syncing: VFS: Unable to mount root fs on unkown-block(33,3)

and not
VFS: cannot open root device "2103" or unkown-block(33,3)
Please append a correct "root=" boot option
kernel panic - not syncing: VFS: Unable to mount root fs on unkown-block(33,3)
<7>ieee1394: Host added: ID:BUS[0-00:1023] GUID[0011060001169031]

which i got before

i tried also to set ADVANCED PARTITION SELECTION = n
and checked that CONFIG_BLK_DEV_IDEDISK=y

nothing helped
i get the kernel panic error

next i tried to switch the harddisk from IDE3 to IDE2 of my 4 IDE channels
during kernel boot i recognized, that the kernel checked the harddisk as hdc right after he checked the cd drive (hda)
if i switch back to IDE3 it only recognizes hda = cdrom!!

i also searched on bugzilla.kernel.org
and now i think it's a kernel bug because there are a few threads when you search for "unable to mount root fs"
link (Added url tags. --pjp)
and this thread
http://bugzilla.kernel.org/show_bug.cgi?id=1823
says there are about 3000 links if you search google for "unable to mount root fs"
well i got 13800 links, but the thread is from year 2004 *g*

i'm asking myself if i should try to compile with kernel 2.4?
many problems occured while upgrading to kernel 2.6

*thinking* ;-)

thinking · n00b Joined: 22 May 2005 Posts: 46

hiho@ll

i tried it with 2.4.29 kernel
the same problem again

well, seems it's not a kernel bug *g*

any suggestions?

thinking · n00b Joined: 22 May 2005 Posts: 46

hiho@ll

here again
and my system works now!!!!
first thx@ll

what i did:
1. i compiled everything into the kernel which has something to do with filesystems (ext3,raiserfs, ide drivers, sata drivers, scsi,....)
2. i got an error message:
Kernel panic - not syncing: No init found. Try passing init = option to kernel
3. i changed fstab and lilo until it runs
i don't really know what it was that i changed to make it work
but if i get the init kernel panic and i use an kernel parameter "root=/dev/hde3" it could boot
maybe i changed lilo.conf before and then i changed it back to root=/dev/hde3
i don't know
but now it works

thx@ll

May the TUX be with you
linux rulez ;-)

RayDude · Posted: Thu May 26, 2005 9:35 pm Post subject:

lordkur