ms-sys - write Microsoft boot block

ms-sys [options] [device]

ms-sys is for writing Microsoft compatible boot records.

A summary of options is included below.

-1, --fat12

Write a FAT12 floppy boot record to device.

-2, --fat32nt

Write a FAT32 partition NT boot record to device.

-3, --fat32

Write a FAT32 partition DOS (Win9x) boot record to device.

-6, --fat16

Write a FAT16 partition DOS (Win9x) boot record to device.

-l, --wipelabel

Reset partition disk label in boot record.

-p, --partition

Write partition info (hidden sectors and drive id) to boot record. This might be needed on some partitions depending on which program was used to create the file system.

-m, --mbr

Write a Windows 2000/XP/2003 master boot record to device. Does not change Windows Disk Signature (bytes 01b8-01bd). This MBR will boot certain partition types beyond cylinder 1024 using LBA addressing.

-9, --mbr95b

Write a Windows 95B/98/98SE/ME master boot record to device. Does not change Windows Disk Signature (bytes 01b8-01bd) or boot drive and time (bytes 00da-00df). This MBR will boot FAT-LBA partition types 0c and 0e beyond cylinder 1024 using LBA addressing.

-d, --mbrdos

Write a DOS/Windows NT master boot record to device. Does not change Windows Disk Signature (bytes 01b8-01bd). This MBR will not boot beyond cylinder 1024 as it does not support LBA addressing.

-s, --mbrsyslinux

Write a public domain syslinux master boot record to device. Does not change Windows Disk Signature (bytes 01b8-01bd). This MBR will boot any partition types beyond cylinder 1024 using LBA addressing.

-z, --mbrzero

Write an empty (zeroed, non-bootable) master boot record to device. Zeroes all bytes except the partition map and signature (bytes 01be-01ff). Similar to the empty DOS partition table that fdisk creates.

-f, --force

Force writing of boot record.

-h, --help

Show summary of options.

-v, --version

Show program version.

-w, --write

Write automatically selected boot record to device.

If ms-sys is started without any options a simple diagnosis will be done on the given device.

Please note that Windows ME is not useful for making standalone bootable floppies. However, Win9x and DOS works fine with the first two examples.

Creating a 1.68 MB bootable floppy

This example assumes that you have your windows installation mounted at /dosc and also have mtools and fdformat installed.

fdformat /dev/fd0u1680

mformat a:

ms-sys -w /dev/fd0

mcopy /dosc/io.sys a:

mcopy /dosc/msdos.sys a:

mcopy /dosc/command.com a:

Creating a bootable 2.8 MB floppy image to use with an el-torito bootable CD

dd if=/dev/zero of=floppy288.img bs=1024 count=2880

/sbin/mkdosfs floppy288.img

ms-sys -1 -f floppy288.img

su

mount -o loop floppy288.img /mnt

cp msdos.sys /mnt/

cp io.sys /mnt/

cp command.com /mnt/

(it might also be a good idea to add a config.sys and autoexec.bat with CDROM support)

umount /mnt

exit

cp floppy288.img cd-files/boot.img

mkisofs -b boot.img -c boot.cat -o cdimage.iso cd-files

(burn the file cdimage.iso to a CD with cdrecord or another program)

restoring a backup of Win9x or Win ME to a fresh hard disk

Step 1, use GNU parted to create your FAT32 partition and file system:

parted (then create partition and file system)

Step 2, write the MBR:

ms-sys -w /dev/hda

Step 3, write the FAT32 partition boot record:

ms-sys -w /dev/hda1

Step 4, mount your new filesystem:

mount /dev/hda1 /mnt

Step 5, read your backup

cd /mnt; tar -xzvf /path/to/my_windows_backup_file.tgz

The variables LANG and LC_ALL have the usual meaning, however there are not many translations available.

There have been reports about unbootable FAT32 partitions created with "mformat -F c:". One workaround is to use gnu parted to create the partition instead. Since version 1.1.3 ms-sys has the switch -p which is supposed to fix this problem. The problem has also been reported on partitions formatted with mkdosfs and mkfs.vfat.

This manual page was originally written by G[:u]rkan Seng[:u]n and since edited by Henrik Carlqvist. The program ms-sys is mostly written by Henrik Carlqvist, the file CONTRIBUTORS in the source archive contains a complete list of contributors.

mformat(1) fdformat(8) mkdosfs(8) mkisofs(8)