Creating a bootfloppy
Create an empty image the size of an 1.44 meg floppy
$ dd if=/dev/zero of=bootdisk.img bs=512 count=2880
Create a dos file system on it using mkfs.msdos (part of the dosfstools package):
$ mkfs.msdos bootdisk.img
List your files with mdir (part of the mtools package):
$ mdir -i bootdisk.img
Volume in drive : has no label
Volume Serial Number is D443-3665
Directory for ::/
No files
1 457 664 bytes free
Now create a directory using mmd:
$ mmd -i bootdisk.img boot $ mmd -i bootdisk.img boot/grub
and copy stage1 and stage2 to the disk and configure GRUB:
$ mcopy -i bootdisk.img /usr/lib/grub/i386-pc/* ::/boot/grub
and verify the result with mdir:
$ mdir -i bootdisk.img boot/grub Volume in drive : has no label Volume Serial Number is D443-3665 Directory for ::/boot/grub .2011-09-15 21:11 .. 2011-09-15 21:11 E2FS_S~1 13728 2011-09-15 21:18 e2fs_stage1_5 FAT_ST~1 11824 2011-09-15 21:18 fat_stage1_5 FFS_ST~1 10592 2011-09-15 21:18 ffs_stage1_5 ISO966~1 10592 2011-09-15 21:18 iso9660_stage1_5 JFS_ST~1 12800 2011-09-15 21:18 jfs_stage1_5 MINIX_~1 10592 2011-09-15 21:18 minix_stage1_5 REISER~1 14624 2011-09-15 21:18 reiserfs_stage1_5 stage1 512 2011-09-15 21:18 stage2 147440 2011-09-15 21:18 STAGE2~1 147440 2011-09-15 21:18 stage2_eltorito UFS2_S~1 10996 2011-09-15 21:18 ufs2_stage1_5 VSTAFS~1 10080 2011-09-15 21:18 vstafs_stage1_5 XFS_ST~1 14856 2011-09-15 21:18 xfs_stage1_5 15 files 416 076 bytes 1 037 824 bytes free
enter the grub terminal by running:
$ grubsetup with grub:
grub> device (fd0) bootdisk.img grub> root (fd0) Filesystem type is fat, using whole disk grub> setup (fd0) Checking if "/boot/grub/stage1" exists... yes Checking if "/boot/grub/stage2" exists... yes Checking if "/boot/grub/fat_stage1_5" exists... yes Running "embed /boot/grub/fat_stage1_5 (fd0)"... failed (this is not fatal) Running "embed /boot/grub/fat_stage1_5 (fd0)"... failed (this is not fatal) Running "install /boot/grub/stage1 (fd0) /boot/grub/stage2 p /boot/grub/menu.lst ".. . succeeded Done. grub> quit
run the system with bochs:
$ bochs -q
There is no menu.lst and no kernel image, that is later work...
Putting this all together into a bash script:
#!/bin/bash
# Creates an empty floppy with grub loader on it.
# Filename:
FLOPPYFILE=emptybootdisk.img
# Create file of 1.44M size:
dd if=/dev/zero of=$FLOPPYFILE bs=512 count=2880
# Create filesystem:
mkfs.msdos $FLOPPYFILE
# Create grub directory:
mmd -i $FLOPPYFILE grub
# Copy grub files:
mcopy -i $FLOPPYFILE /usr/lib/grub/i386-pc/* ::/grub
# Run grub commands in batch mode:
grub --batch <<THEEND
device (fd0) ${FLOPPYFILE}
root (fd0)
setup (fd0)
quit
THEEND
# List files on floppy:
mdir -i $FLOPPYFILE