old bios needs /boot partition on large disk

[Steve R. Hastings]

Older bios can not access the entirety of new large disks. The workaround to this is to create a /boot partition ( 100-200mb should do it ) near the start of the disk. It has been suggested that the installer do this by default, but this has been rejected due to it complicating the already fragile dos partitioning scheme and not being needed for the vast majority of people.

[Matt Zimmerman (mdz)]

Colin, do you think it will eventually be possible to detect this condition and
fail gracefully before rebooting? If not, there isn't much we can do with this bug.

[Colin Watson (cjwatson)]

Or we could change our partman-auto recipes to create a /boot partition, as the
submitter suggests. In fact, joeyh suggested something similar a while back too.

[Matt Zimmerman (mdz)]

I encountered this error recently when doing an install. The system had Windows
98 installed, which I resized using the Ubuntu installer, created a new
partition for Ubuntu and installed the first stage (including GRUB)
successfully. However, upon reboot, GRUB gave error 18.

I was able to correct this by:

- setting the BIOS drive geometry to "auto" (it was set to "LBA", which oddly
enough produced different geometry values)
- re-running grub-install '(hd0)' via chroot from the installation CD

I fully expected this to make the partitions unreadable due to the geometry
change, but to my surprise it fixed the problem, and both Ubuntu and Windows 98
booted fine. Re-running grub-install may or may not have been necessary; I
don't think I tried to boot it again until both steps were complete.

[therayman (rgboudreau)]

Created an attachment (id=1166)
Grub error 18 with Hoary or Ubuntu 4.10

[Martin Uecker (muecker)]

*** Bug 12343 has been marked as a duplicate of this bug. ***

[James Muirhead (james-placebo)]

I had exactly the same problem when installing Warty Warthog. In the end I
installed Hoary Hedgehog anyhow but I created a 20MB primary boot partition
mounted as /boot. Then having a 19GB logical for the rest of the data mounted as
/ and a 1GB swap file.

Fixed the problem, now it works as if there was never a problem in the first place.

PS - The computer I was installing Ubuntu on did have support for larger HDDs,
but seemed to cause the error anyway!

[Chuck Short (zulcss)]

According to the bug reports this is fixed.

[Colin Watson (cjwatson)]

(In reply to comment #7)
> According to the bug reports this is fixed.

Err, a commenter worked around it by creating a small /boot partition manually.
I don't think that really counts as "fixed".

[Kulin (kulinp)]

Tried to install Ubuntu Dapper Flight 5 (AMD64). Came across the same error -- Grub Error 18 while booting for the first time. I'm installing on an external USB hard drive (but I don't think that should matter). I will try creating a small /boot and post an update.

[Yajun Wang (yalding)]

I install ubuntu dapper RC from live CD. Same error appears upon boot.

[Richard Boulton (richardboulton)]

I've just run into this problem when upgrading from Breezy. The machine started with a clean install (well, used for 8 months, but otherwise reasonably unsullied) of Breezy, which worked fine. Upgrade to Dapper yesterday went fine; once everything was installed I rebooted, and grub left me in its command prompt.

Trying to read menu.lst (by running "cat /boot/grub/menu.lst") displays Error 18.

As far as I know, my BIOS supports large disks (at least, the BIOS provides an option for LBA addressing, which is checked).

Will try adding a /boot partition.

[Step (random4444)]

Just installed from Live CD onto old Windows box. Put in a new 250 GB HD as master, moved 20 GB with Win XP to slave. Used default Ubuntu options to format and autopartion 250 GB drive, then got error 18 on restart.

Original poster's idea is a good one - change to having a /boot partion by default. I also found a thread (http://www.ubuntuforums.org/showthread.php?t=43061) that mentioned just changing the root partition to logical instead of primary. I am going to try that first.

[Kurt J. Bosch (kujub-deactivatedaccount)]

I recogniced a similar bug since edgy:

https://bugs.launchpad.net/ubuntu/+source/grub/+bug/79578

Since I use grub from dapper there was no problem.

[David Vinas (dvinas)]

I am having the same problem with Feisty Beta. I am going to try updating my BIOS and see if that works. Otherwise, I am at a loss for what to do. I have a 160GB HD split 130/30 (XP/Linux). Ultimately, I plan to use the whole drive for Linux, but for now, I need to retain this configuration.

[Michael S (michael-speechley)]

Hi, I've just set up a machine with Ubuntu 7.10 Desktop (master) and Windows XP (slave) and had the "Error 18" on start up. However after reading this thread I solved the problem by letting the BIOS detect (IDE HDD Auto Detection) the hard drives cylinders, heads and sectors instead of using the "Auto" setting.

[rusivi2 (rusivi2-deactivatedaccount)]

Thank you for posting this bug.

Ubuntu 7.10 is in End of Life status. Please update and repost detailed error report.