Softpanorama (slightly skeptical) Open Source Software Educational Society

May the source be with you, but remember the KISS principle ;-)

Technology of Working with Floppy Images

A disk image is a file which contains the full contents of the specified disk in a single file; the contents are generally read as raw sectors so all data including partition information (FAT), boot sector, along with actual directory entries and files are copied to the image. An image file is specific to a particular format, so a 1.44MB image should be written to a 1.44MB floppy diskette and 1.2MB image should be written to a 1.2MB floppy diskette. However, some programs may support cross diskette writing (i.e. 1.2MB disk image to a 1.4MB disk drive) and hard drive images can often (though really depends on what the used program supports) be written to hard drives of the same or larger size [possibly adjusting data to resize partition and take advantage of additional size]. A disk image is different from an archive [zip/arj/etc.] as it contains a snapshot (or image) of the contents and does not differentiate between OS data (FAT/etc.) and user data (particular files/directories/etc.); which are not generally accessible until written back to a disk; and use different means to access the data bypassing the OS's filesystem layer; also a diskimage will generally produce identical disk copies, whereas archives generally are equivalent to copying the files to a new diskette. See http://www.rundegren.com/software/floppyimage/faq/ for additional information about disk images.

You must write each of the image files you need to a floppy disk. The easiest methods of writing an image file to a disk are using dd or rawrite.  Good old wimage (part of FDFORMAT, a shareware package for DOS written by Christoph H. Hochsttter) can also be useful.  To create image in Windows 2000 one can use dcf

Old News ;-)

Re how to write a floppy using dd

There are two basic ways of copying the boot images to floppys.
One is by using dd: dd if=1440_boot_floppy of=/dev/fd0  -- of course
use your own intended floppy device.

The second might be a little quicker:

cat 1440_boot_floppy >/dev/fd0

I have used both ways at different times and they work the same.
There is probably quite a tech. difference, but I don't think that there
is a functional difference.

Have Fun!

Recommended Links

**** Rawrite and related programs very good page by Jeremy Davis

Marc's realm - Creating and using disk images mini-HOWTO

Rawrite Wikilearn TWiki

Thomas Rude - DD and Computer Forensics

Using dd (instead of cdrecord and dvdrecord) to write bootable ISO images to DVD-RAM disks - CCP14 Linux Internet Server - CCP14 Web-Config Administration Information - CCP14 Homepage - Single Crystal and Powder Diffraction

Making Diskette Images without Diskettes

So far we have been preparing boot diskettes by writing to real diskettes. This sounds like the most logical way to do it, but there can be reasons why we want to prepare an image file of a diskette without using real diskettes. Several reasons could be:

• Create a diskette image for a diskette drive you do not have.
• Automate boot image creation (several diskette images for a distribution).
• Create a diskette image for bootable CD-ROM
• Create a diskette image for a PC emulator

Basically we could create a diskette image as follows:

• Create an all zero image file using dd.
• Create a file system onto the image file.
• Mount the image file using the loop option and copy all files to it.
• Install the boot loader onto the image file.

The last part is the trickiest especially for LILO. It's fairly trivial for SYSLINUX and using the device command it can be done with GRUB. There is also another trick for SYSLINUX and GRUB (it does not work with LILO):

• Start with an image file with just the boot loader installed and an empty file system and copy that image file each time you create another image. This image file may be extracted from a real diskette just once.
• Mount the image file using the loop option and copy all files to it.

On Timo's Rescue CD Page there is a good explanation of how to create 2.88MB diskette images for a bootable CD-ROM, using all boot loaders. I could not explain it better. Of course these recipes apply also to other types of disk images.

Marc's realm - Creating and using disk images mini-HOWTO

Thomas Rude - DD and Computer Forensics - He's Worth a Deuce!

Moving your data to a backup device

Using the dd command to dump data

The dd command can be used to put data on a disk, or get it off again, depending on the given input and output devices. An example:

gaby:~>dd if=images-without-dir.tar.gz of=/dev/fd0H1440
98+1 records in
98+1 records out

gaby~>dd if=/dev/fd0H1440 of=/var/tmp/images.tar.gz
2880+0 records in
2880+0 records out

gaby:~>ls /var/tmp/images*
/var/tmp/images.tar.gz

Note that the dumping is done on an unmounted device. Floppies created using this method will not be mountable in the file system, but it is of course the way to go for creating boot or rescue disks. For more information on the possibilities of dd, read the man pages.

This tool is part of the GNU fileutils package.

Dumping disks

The dd command can also be used to make a raw dump of an entire hard disk.

Rawrite

raw write program  looks like version 1.3 is the latest. It's a single exe file

rawrite -- Suse archive contain rawrite.exe and rawrite3.com: the latter has parameters (-d -f)  There is also rawrite2 program written in Pascal looks like semidebugged (not working under Windows 2000) analog of wimage.  Because of problems with win2000 does not have any advantages  over wimage.

DCF: Disk Copy Fast This DOS shareware tool can read/write/format image files compatible with WinImage under MS-Dos. Works under Win2K. ftp://ftp.simtel.net/pub/simtelnet/msdos/diskutil/dcf5_3.zip
 http://ourworld.compuserve.com/homepages/dcf_hdcp/DCF53.ZIP

** ? WinImage WinImage looks like a wimage based utility. Too complex to be useful.

Softlookup.com - Floppy Image Creator-Display Information

Floppy Image Creator  This utility can work with any of the standard floppy disk formats: 720kb and 1.44Mb 3.5" disks, as well as 360kb and 1.2Mb 5.25" disks.  You can also include a description of the disk with the image file.

Muckshifter's Forum - Image Maker 1.1 free

The FREE ImageMaker 1.1 does not support image compression and encryption. These features will be added in a future shareware version of ImageMaker. The image of an entire hard drive may be restored only to a hard drive, not a partition, and vice versa. After restoring a disk partition backup, a reboot is required to see the restored disk contents. After restoring entire hard disk backups, or in any other cases, no reboot is requred. The download is very small, at just 476KB.

DCF

DCF: Disk Copy Fast This DOS shareware tool can read/write/format image files compatible with WinImage under MS-Dos. Works under Win2K. ftp://ftp.simtel.net/pub/simtelnet/msdos/diskutil/dcf5_3.zip
 http://ourworld.compuserve.com/homepages/dcf_hdcp/DCF53.ZIP

Wimage

Good old wimage (part of FDFORMAT, a shareware package for DOS written by Christoph H. Hochsttter) can still be useful. 

• Index of -pascal-UNITS-FDFORM
• Evseev's download page

Etc

Muckshifter's Forum - Image Maker 1.1 free

The FREE ImageMaker 1.1 does not support image compression and encryption. These features will be added in a future shareware version of ImageMaker. The image of an entire hard drive may be restored only to a hard drive, not a partition, and vice versa. After restoring a disk partition backup, a reboot is required to see the restored disk contents. After restoring entire hard disk backups, or in any other cases, no reboot is requred. The download is very small, at just 476KB.

Rundegren.com - Floppy Image OK program but will cost you $15. There are some free older versions.

Create image files of floppy disks and back (for backup, shipping or transfer). Save the image file compressed, uncompressed or as a self-extracting exe. Add descriptions to or convert your old image files. Supports DMF and other non-standard formats. Logically recreate bad sectors when writing floppy disks, allowing for an exact duplicate of your source disk to be created. The self-extracting exe can be fully customized with a picture, license agreement dialog and a text with instructions. Full support for drag-n-drop.

NOTE: Formatting of non-standard formats and recreating bad sectors logically are only available on Windows NT4/2000/XP.

Softlookup.com - Floppy Image Creator-Display Information

Floppy Image Creator  This utility can work with any of the standard floppy disk formats: 720kb and 1.44Mb 3.5" disks, as well as 360kb and 1.2Mb 5.25" disks.  You can also include a description of the disk with the image file.

Last modified: June 05, 2008