Red Hat Bugzilla – Bug 47399
error booting grub floppy
Last modified: 2015-01-07 18:47:13 EST
Description of Problem:
The grub info documentation says that you can create a grub floppy by
dd'ing stage1 and stage2 to a floppy disk. However, booting this floppy
gives an error during stage2.
Steps to Reproduce:
1. fdformat /dev/fd0H1440
2. dd if=/boot/grub/i386-redhat/stage1 of=/dev/fd0 bs=515 count=1
3. dd if=/boot/grub/i386-redhat/stage2 of=/dev/fd0 bs=512 skip=1
4. boot the floppy
error in stage2
The info documentation actually says:
dd if=stage2 of=/dev/fd0 bs=512 seek=1
This worked for me.
I am reopening this because there is a "bug" of sorts.
Sometime after closing this report previously, I tried to build another grub
boot floppy using the dd of stage1 and stage2 and again I came up with something
that got an error only this time I very importantly used the seek=1 for stage2.
After some experimenting and comparing stuff with hexdump, I have found the
problem: to create a stage1/stage2 grub boot floppy, you MUST use a stage2
which is NOT being used by grub on a harddisk. That is, you must use a stage2
from a system where grub is not installed and lilo or a boot-floppy-only is used.
1. update the (info) documentation to reflect this situation.
2. Change the grub rpm to install a second copy of stage2 as something like
3. Optionally, create a man page such as grub.floppy to explain this.
Pristine grub stages are now properly in /usr/share/grub/i386-redhat... also,
you might want to try /sbin/grub-install /dev/fd0 since it's easier =)
Applies to grub-0.90-6 and up