grub error 18

David Kuntadi d.kuntadi at
Mon Sep 21 07:29:36 UTC 2009

On Mon, Sep 21, 2009 at 2:06 PM, Christopher Chan
<christopher.chan at> wrote:
> When I reinstall grub in the LiveCD environment and then reboot the
> machine to let it boot up the installed Jaunty, there is no problem.
> That demonstrates that there is no 1024 cylinder problem even though
> this is an older machine. However, that grub installation that I did
> from the LiveCD environment is apparently being overwritten whenever I
> shutdown since I get the weird error 18 message from grub on the next
> attempt to boot.

Is there any proof/clue so that you think it is overwritten? I still
guess that the bios read the partition differently after upgrade, but
not sure why. I have not have this issue so far after using uuid.

But to confirm that it is not what I suspected, could you check
/etc/fstab before and after reinstall Grub.
In additio to that, do:
Before reinsall:
ls -n /dev/disk/by-uuid > before.txt

After resintall:
ls -n /dev/disk/by-uuid > after.txt

And compare before.txt. and after.txt if there is any change.

As you do not  think it is location of the kernel:
Quoted what you wrote:
> grub cannot even load stage1.5 when it is error 18...i don't think it is
> anything to do with the location of the kernel.

Please see below writing:
Error 18

Error 18: Selected cylinder exceeds maximum supported by BIOS

This error is returned when a read is attempted at a linear block
address beyond the end of the BIOS translated area. This generally
happens if your disk is larger than the BIOS can handle (512MB for
(E)IDE disks on older machines or larger than 8GB on others.). In more
practical terms this means the BIOS is unable to start executing the
kernel because the kernel is not located within the block it can
access at boot up time.

Read more:


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