Kernel Panic - Unable to mount on unknown-block

[pascal16]

I have just compiled the 2.6.10 kernel making sure that ext2 and ext3 filesystem support is compiled in, but I am now unable to boot into it, as I get this error message:

Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block (0,0)

I think this may be due to an error I made in adding an entry for the new kernel in grub (although I modelled it on the other entries that were already there). My grub.conf is below:

# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You have a /boot partition. This means that
# all kernel and initrd paths are relative to /boot/, eg.
# root (hd0,5)
# kernel /vmlinuz-version ro root=/dev/VolGroup00/LogVol00
# initrd /initrd-version.img
#boot=/dev/sda
default=3
timeout=10
splashimage=(hd0,5)/grub/splash.xpm.gz
hiddenmenu
title Fedora Core (2.6.9-1.667smp)
root (hd0,5)
kernel /vmlinuz-2.6.9-1.667smp ro root=/dev/VolGroup00/LogVol00 rhgb quiet
initrd /initrd-2.6.9-1.667smp.img
title Fedora Core-up (2.6.9-1.667)
root (hd0,5)
kernel /vmlinuz-2.6.9-1.667 ro root=/dev/VolGroup00/LogVol00 rhgb quiet
initrd /initrd-2.6.9-1.667.img
title Fedora Core (2.6.10)
root (hd0,5)
kernel /vmlinuz-2.6.10 ro root=/dev/VolGroup00/LogVol00 rhgb quiet
title Windows XP
rootnoverify (hd0,1)
chainloader +1

The hard drive is a SATA one, if that makes any difference.

Any help would be greatly appreciated

[amazoneveryday]

Darn it if I'm not have the exact same problem with 2.6.11, and I've compiled kernels before. This is the first one to stump me...

[amazoneveryday]

By jove, I think I've got it!

You absolutely MUST have initial ram disk support compiled into your kernel (not as a module). As far as I can tell, without it compiled into your kernel the initrd file can't be mounted properly. Do make menuconfig and it's under "filesystems" IIRC

Good luck and happy hacking!

It worked for me... I boot 2.6.11 just fine now.

[imdeemvp]

Did you move your hard drives around? More and more I see this being the case....

[amazoneveryday]

Originally Posted by imdeemvp

Did you move your hard drives around? More and more I see this being the case....

I sure didn't... I had compiled successfuly the 2.6.10 and 2.6.7 kernels without this problem. It only happened to me with 2.6.11

[pascal16]

Running the mkinitrd command in the kernel source directory fixed it for me.

[GaryG]

Your grub default entry is 3; the third entry in grub.conf does not have and "initrd" entry --- would this cause your problem????