swCHIP 1991 January/swCHIP_95-1.bin/chip/copy/fips12/fips.doc

Text File | 1995-12-11 | 26KB | 577 lines

                  Welcome to FIPS
    The First nondestructive Interactive Partition Splitting program

                Version 1.1.1
                   october 13, 1994

             Copyright 1993/94 by Arno Schaefer


0.  What you need to use FIPS
1.  Introduction
2.  What FIPS does
3.  Safety
4.  Restrictions
5.  Before you start
6.  Use with Stacker/SuperStor/Doublespace
7.  Use with OS/2
8.  Use with a multitasking OS
9.  Use with OnTrack Disk Manager
10. Using FIPS
11. After splitting the partition
12. Commandline Switches
13. Troubleshooting
14. Credits


FIPS is a program designed to split an existing DOS partition without deleting
the data on it.

FIPS is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

FIPS is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with FIPS; see the file COPYING.  If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

Report problems and direct all questions to:

    [e-mail]


0. What you need to use FIPS

You need a defragmentation program in order to move all data to the beginning
of the hard disk. FIPS will only split your partition if you have enough free
space at the end. DOS 6.0 and later contains DEFRAG, which is suitable for
this purpose. Other suitable programs are Norton Speedisk (actually DEFRAG
is speedisk with less functions, licensed from Norton), PCTools' Compress,
DISKOPT in Novell DOS 7, or the shareware programs ORG, DOG or SAFPAK
(available by anonymous FTP from any SIMTEL mirror in the diskutil directory).
I did not test these however, so don't blame me if they don't work for you.

You may also want to use a program like Norton Disk Doctor (or 'scandisk'
in DOS 6.2) to check your harddisk before and after using FIPS.

FIPS was developed under DOS 5.0. It should work fine with anything above
3.0, perhaps even with 2.0. However it will not be of much use with older
DOS versions, since the large partition sizes are only available since DOS 4.
It has been reported to work with DOS 6.0 and 6.2 and Novell DOS 7.


1. Introduction

The program was inspired by the Linux Project. When installing Linux on a
PC that was used for DOS / Windows, many people want to retain a smaller
partition for their DOS software. However, since most Harddisks contain
only one large partition, you would normally be required to do a complete
backup, erase the partition and build two (or more) new partitions. Then you
would restore the backup to one of the new partitions.
This is a very time consuming activity and requires lots of floppy disks
(why buy 50+ disks only to once backup and restore your HD?).
FIPS was written to remedy this problem. You can now split a partition
without losing any data, provided there is enough free space for the new
partition at the end of the old one.


2. What FIPS does

FIPS reduces the size of a partition by changing some values in the
partition table and boot sector. It does not change the formatting of
the partition, especially not the cluster size and the size of the file
allocation table (FAT). Therefore the reduced partition will have a FAT
that is partly unused, but this is not a problem for DOS.

From the free space that is won by this, FIPS creates a new _primary_ DOS
partition.

If you want to use the new partition under a different OS (e.g. Linux), use
its supplied fdisk program to make any necessary changes (refer to the OS
manuals).

If you want to use the new partition under DOS/Windows, you can use it as
it is (after formatting), but be aware of the following:

According to the official references, DOS can only have one primary
partition. All DOS versions (at least from v5.0 on) will happily work with
multiple primary partitions, but this is an 'undocumented feature'. If
you want to follow the official rules, you can delete the new partition with
fdisk and create an extended partition in its place.

There are reasons for having multiple primary partitions, among them the
possibility to boot from different partitions by changing the active par-
tition with fdisk.

Known problems with multiple primary partitions are:

- If you accidentally delete one primary partition with fdisk, you can not
  easily recreate it, since fdisk will refuse to. There may be other fdisk
  programs around that work, and if all else fails you can boot from a
  Linux boot disk to run Linux' fdisk, but it is always a hassle.

- There exist some software packages that work with the partition table and
  which may be confused by multiple primary partitions. Among them was SFS,
  the 'Secure file system' by Peter Gutmann. I think Peter has made a change
  to his program to accept some unusual configuration, but there may exist
  other software packages that will have problems.


3. Safety

FIPS was specifically designed to provide a maximum of safety. On startup
it checks the Partition Table, Boot Sector and FAT for any inconsistencies.
If it finds anything suspicious, it will tell you so. If there are errors,
FIPS will not proceed.
You have the possibility to write backup copies of your root and bootsector
to a floppy disk before proceeding. If something goes wrong, you may restore
these with the program 'restorrb.exe' (see section 5).
After you have entered the start cylinder for the new partition, FIPS will
check if the new partition is completely empty by examining the FAT of the
old one. If it is not, FIPS will stop.
After having calculated the new Partition Table and Bootsector, FIPS will
check them again, so that eventual bugs in the calculation may be detected.
Only if everything is ok, FIPS will ask for permission to write the new
Root and Bootsector.


4. Restrictions

FIPS will only work with Hard Disk BIOSes that use interrupt 13h for low
level harddisk access. I think this is true for practically all PCs.

FIPS will only work on disks with a sector size of 512 bytes.
It seems that DOS is prepared to deal with different sector sizes, but
so far I have never seen this.

FIPS will not split partitions with 12 bit FATs (you would not want to split
partitions with less than 10 MB, would you?).

FIPS will only split DOS partitions. Partition Table and Bootsector must
conform to the MSDOS 3.0+ conventions. This is marked by the system
indicator byte in the partition table, it must have the value 4 (16 bit
sector number) or 6 (32 bit sector number).
It will especially *not* split Linux partitions.

FIPS does not yet work on extended DOS partitions. Support for these has
been planned for a long time, but I can't say when it will come.

FIPS will not work if you already have four partitions, since it needs one
free partition entry.

FIPS will not reduce the original partition to a size with less than 4085
clusters, because this would imply rewriting the 16 bit FAT to a 12 bit FAT.


5. Before you start

Run CHKDSK or (under DOS 6.2) SCANDISK on the partition you want to split.
If you have Norton Disk Doctor or something similar, you may use it alter-
natively. Make sure there remain no 'dead' clusters on the disk.

Prepare a bootable floppy disk in drive A:. Under DOS this is usually done
by giving the command 'sys a:' or 'format a:/s'. Under Windows NT or OS/2
this may be different, if in doubt you should check your manual.

Copy the FIPS files RESTORRB.EXE, FIPS.EXE and ERRORS.TXT to this disk.

Test booting from the prepared floppy disk. Read you manual or ask a local
guru if you can't boot from floppy disk or if you can not access your hard
disk after booting (test this by giving the command 'dir c:', you should
see your hard disk's root directory). If all else fails, try using FIPS
after booting normally from the hard disk (a bit more risky, but sometimes
the last resort).

When you start FIPS (later!), you will be given the opportunity to write
backup copies of your root and boot sector to a file on drive A: called
ROOTBOOT.00x (where x stands for a digit from 0 to 9). If anything goes wrong
while using FIPS, you can restore the original configuration by booting from
the floppy and running RESTORRB. Please note: if you use FIPS more than once
(this is normally not necessary, but it may happen), more than one ROOTBOOT
file is written to the floppy disk. RESTORRB lets you choose which configu-
ration file to restore. The file RESTORRB.000 contains your original confi-
guration. Try not to confuse the versions.

You will need this backup file (ROOTBOOT.00x) if you want to undo the
partition split later.

But before starting FIPS you _must_ now defragment your Harddisk. All of the
space that will be used for the new partition must be free. Be aware that the
Windows Swapfile will not be moved by most defragmentation programs. You must
uninstall it (in the 386enhanced part of the Windows Control Panel) and rein-
stall it after using FIPS.
If you use IMAGE or MIRROR, the last sector of the hard disk contains a
hidden system file with a pointer to your mirror files. You _must_ delete this
file before using FIPS (it will be recreated the next time you run mirror).
Do 'attrib -r -s -h image.idx' or 'attrib -r -s -h mirorsav.fil' in the root
directory, then delete the file.
If FIPS does not offer as much disk space for creation of the new partition
as you would expect it to have, this may mean that

a. You still have too much data in the remaining partition. Consider making
   the new partition smaller or deleting some of the data.

b. There are hidden files in the space of the new partition that have not
   been moved by the defragmentation program. Make sure to which program
   they belong. If a file is a swap file of some program (for example NDOS)
   it is possible that it can be safely deleted (and will be recreated
   automatically later when the need arises). See your manual for details.

   If the file belongs to some sort of copy protection, you must uninstall
   the program to which it belongs and reinstall it after repartitioning.

   I can't give you more aid in this - if you really can't figure out what
   to do, contact me directly.

Attention! If you use a DOS version lower than DOS 5.0 do _not_ try to move
DOS' hidden system files (ibmbio.com & ibmdos.com or something similar). You
will end up with a harddisk that won't boot any more. Since these files are
already in the first sectors of the partition, it is not necessary to move
them.

Be aware that the location of your DOS partitions in the partition table may
change. If you use the new partition under DOS _and_ you have an extended
partition and/or two drives, this means that the names of the partitions may
change (D: may become E: for example). I have taken care that C: always re-
mains C:, so that you will still be able to boot.

For Linux users:
This also means that the device number of the DOS partition under Linux may
change (/dev/hda3 may become /dev/hda1). Any existing Linux partitions will
not change, so that you will have no trouble booting. You just need to edit
your /etc/fstab file if you mount your DOS partition on bootup.


6. Use with Stacker/SuperStor/Doublespace

I received reports that the following scheme works with Stacker, it may also
work with the other programs. I can't confirm this, since I don't use any of
these programs.

a. Make sure that there is enough space on the compressed partition to be
   split.
b. Use the Checkdisk program that comes with the compression software.
c. Remove the Windows swapfile (if you have one).
d. Decrease the size of the compressed volume with the utilities that come
   with the compression software.
e. Boot without the compression device driver.
f. Look at the directory listing to see how much space is available for the
   new partition.
i. use FIPS as described below.

If the compressed volume is fragmented, FIPS will not offer as much space
for the new partition as is shown in the directory listing. I would not
expect this to happen, normally the compressed volume should be one block
of consecutive sectors. But if it happens to you, you should add the fol-
lowing steps.

g. Remove Hidden, Readonly and System attributes from compressed volume.
h. Defragment the partition.

j. Reset Hidden, Readonly and System attributes on compressed volume.

Please let me know if this scheme works for you, so that I can include this
info in later releases. In any case, use at your own risk.


7. Use with OS/2

FIPS is known to have problems with OS/2, especially with the dual boot
feature. This is partly due to the fact that OS/2 dual boot uses two copies
of the boot sector - if only one copy is changed by FIPS, OS/2 will not
work properly.
But even when taking this into consideration, some people have reported
strange error messages by OS/2. If you want to give FIPS a try, make sure
to save the root and boot sector to floppy disk with FIPS before making
any changes. FIPS _might_ work if you

1. Remove dual boot from the partition (if you use it)
2. Boot from a bootable DOS disk
3. Run FIPS (make sure to make FIPS save the root and boot sector to floppy)
4. Reboot, check if everything is ok under DOS
5. Boot from your OS/2 installation disk and reinstall dual boot if
   necessary.
6. Boot to OS/2 and look if everything works as expected.

If 5. does not work (OS/2 complains with 'hardware error' or something
similar), use RESTORRB to undo the changes FIPS made, reboot again and
reinstall dual boot (if necessary).

So far I did not find out what OS/2 complains about. Since I do not use
OS/2, I have to rely on user reports. If you try FIPS with OS/2,
I would like to hear about it. Any information is welcome, even if it
is just "it worked" or "it did not work". If you have an idea what might
be the problem or any technical information, please tell me about it.


8. Use with a multitasking OS

You should not use FIPS in multitasking environments like OS/2, Desqview,
Windows, Novell Task Manager or the Linux DOS Emulator. These systems might
still write to the disk after FIPS has changed the hard disk structure,
which may result in corrupting the disk. This is not necessarily so, I'd
suppose that in most cases it would work nevertheless. But since safety is my
first concern with FIPS, I would recommend booting from a DOS boot disk and
then running FIPS, that should be safe.
In version 1.0 I added some code by Dave McCaldon to detect Windows and
Desqview (thanks, Dave!). OS/2 and Novell Task Manager are not yet detected.
I had to remove the code for detecting the Linux DOS emulator because it
caused a hangup on many machines.


9. Use with OnTrack Disk Manager

OnTrack Disk Manager is a special program that is used with hard disks
with more than 1024 cylinders. It installs its own boot program in the
hard disk's root sector and uses some tricks to make DOS think it has
a disk with less than 1024 cylinders. To use FIPS with OnTrack Dis Manager,
you must load the OTDM driver first. I don't know if it can be loaded from
floppy disk, if not you must boot from the hard disk. After that FIPS
should work as expected.

Note to Linux users: You can not use this scheme to create a Linux
partition. This is because the partitioning information that FIPS modifies
is on a level above the OTDM driver, so you can only access them after
having loaded the driver. Since Linux does not use DOS drivers, it can
not access the new partitions. Your only possibility is to completely
reformat your hard disk.


10. Using FIPS

If you have prepared a bootable floppy disk as described in section 5,
boot from it now.

You start FIPS by typing FIPS at the DOS prompt, followed by <ENTER>.
You may exit from the program at any time by pressing <CTRL-C>.

FIPS will first try to detect under which OS it is running. If it is
Windows or Desqview, it will complain and tell you to boot from a floppy
disk. You can proceed nevertheless, but this is at your own risk (see
section 8).

Then FIPS will detect you hard disks, if you have more than one, it will
ask you which one you want to work on.
In previous releases, FIPS failed to detect the right number of hard disks
with some BIOSes (esp. in Gateway Pentium machines). I hope I have corrected
this. If FIPS fails to detect the correct number of disks, please let me
know. In the meantime you may use the '-d' switch to select the drive
by hand (see below).

FIPS then reads the rootsector of the hard disk and displays the partition
table.

Example:

     |        |     Start      |      |      End       | Start  |Number of|
Part.|bootable|Head Cyl. Sector|System|Head Cyl. Sector| Sector |Sectors  |  MB
-----+--------+----------------+------+----------------+--------+---------+----
1    |    yes |   0  148      1|   83h|  15  295     63|  149184|   149184|  72
2    |     no |   1    0      1|   06h|  15  139     63|      63|   141057|  68
3    |     no |   0  140      1|   06h|  15  147     63|  141120|     8064|   3
4    |     no |   0    0      0|   00h|   0    0      0|       0|        0|   0


If you don't know what to make of this, don't worry too much. You may just use
the number of Megabytes to identify your partitions.

The rootsector is then checked for errors.

If you have more than one partition on the disk, you will be asked which one
you want to split.

The bootsector of the chosen partition is read and some information is dis-
played.

Example:

Bytes per sector: 512
Sectors per cluster: 8
Reserved sectors: 1
Number of FATs: 2
Number of rootdirectory entries: 512
Number of sectors (short): 0
Media descriptor byte: f8h
Sectors per FAT: 145
Sectors per track: 63
Drive heads: 16
Hidden sectors: 63
Number of sectors (long): 141057
Physical drive number: 80h
Signature: 29h


FIPS checks if this information is consistent with the partition table and
tries to detect other errors.

It then verifies if the two copies of the FAT are identical, if they are not,
FIPS will exit with an error message.

If everything checks out ok, FIPS now looks for free space at the end of
the partition. The new partition must have at least one cylinder, so if
the last cylinder is not free, you have no chance of splitting the
partition: FIPS will exit with an error message. Probably you forgot
to remove a mirror or image file (see above).

You must now enter on which cylinder the new partition should start.
Use the cursor keys right/left to increase or decrease the cylinder
count. The size of the remaining partition and the new partition are
displayed in the process, so you will have no trouble choosing the
right cylinder. With cursor up/down you can change the count in steps
of 10. When ready, press enter to continue.

FIPS will check again if the space for the new partition is empty -
this is an additional security measure and should never show an error,
since the free space is already determined before.

After this, FIPS will calculate the changes to the rootsector, check the
changes and display the new partition table. You may now choose to reedit the
partition table (this will return you to the point where you select the par-
tition) or to continue. If you type 'c', FIPS will calculate the changed
bootsector, check it again and prompt you if you want to proceed. If you type
'y' then, FIPS will write the changes to the disk and exit.


11. After splitting the partition

Your new partition will be recognized by DOS after your first reboot. Make
sure to disable all programs that write to your disk in config.sys and
autoexec.bat before rebooting. Your best bet is to rename these two files
or to boot from floppy. You should especially disable MIRROR or IMAGE.
After rebooting, use CHKDSK or Norton Disk Doctor to make sure your old (now
smaller) partition is ok. If you don't find any errors, you may now reboot
with your normal config.sys and autoexec.bat. Start some programs and make
sure you can still read your data.

If you want to use your new partition under DOS, you must format it. If you
have multiple partitions, make sure to format the right one, the drive names
may have changed!
If you want to use the partition under Linux, you may now change the system
indicator byte with Linux' fdisk, then use MKFS.

If you want to split the new partition again in two smaller ones, you must
first format it under DOS, otherwise FIPS will complain.


12. Commandline Switches

Here is the explanation of FIPS' commandline switches. If you prefer the DOS
style, you may use '/' instead of '-' as the switch character. The switches
may be arbitrarily combined. Type 'FIPS -help' to get a list of the switches.
Here is a more detailed explanation:

-t or -test : test mode (no writes to disk)

This doesn't need much explanation.

-d or -debug : debug mode

In this mode, a complete transcript of your session along with some additio-
nal information is written to the file FIPSINFO.DBG in the current directory.
You can send this file to me in case of trouble (see below).
This switch does not interfere with the -d<num> switch.

-h or -help or -? : help page

A short summary of the switches

-d<num>   : select drive <num>

Preselect the drive number with this switch. Valid numbers are 128 to 255.
This may also be used to override the automatic drive detection - if for any
reason the drive is not found by FIPS, you may try this switch.

-p<num>   : select partition <num>

Preselect the partition number (1-4). Only valid partitions are accepted.

-c<num>   : new start cylinder = <num>

Preselect the new start cylinder - only valid cylinder numbers are accepted.

-omb      : override 'More than one bootable Partition'

There are some bootprograms that do not complain about more than one bootable
partition - they will just use the first one. If you have such a program in
your rootsector and the PC boots normally, you may use this switch to skip
the error message. I would recommend however to delete the wrong flags, if
you have a suitable program.

-obf      : override 'Invalid bootable-flag'

By modifying the bootable flag and the bootprogram it is theoretically pos-
sible to boot from the second harddrive. If you happen to have such a confi-
guration, use this switch to skip the error message.

-ore      : override 'Number of Rootdir entries must be multiple of 16'

An invalid number of Rootdir entries is accepted by DOS. If you have no other
means to correct the entry, you may use this switch to skip the error message.

-olf      : override 'FAT too large'

Since the number of sectors per FAT is a 2 byte number, it is theoretically
possible to have up to 65535 sectors per FAT. This is accepted by DOS, but a
number greater than 256 is not useful, since the largest possible FAT has 256
sectors.

-osf      : override 'FAT too small'

If the number of clusters in the partition is larger than there are entries
in the FAT, DOS uses only part of the partition. Something has gone *very*
wrong with this partition, but all is not lost - use this switch and reduce
the partition to a size that can be properly managed.

-omd      : override 'Wrong Media Descriptor Byte in FAT/Bootsector'

The media descriptor byte should be F8h for a harddisk, but other values like
FCh are accepted by DOS (perhaps used for removable media ?), so you can
override the error message with this switch.


13. Troubleshooting

FIPS is still somewhat experimental, although it has been used by many
people successfully and without serious problems.
When in doubt I usually decided to stay safe and display error messages
when encountering suspicious configurations. For some of the minor errors
I added override switches (see section 12).

Please make sure you have read this doc carefully and also look in the file
FIPS.FAQ that covers some frequently asked questions.

If you can't resolve a problem yourself, or have a configuration not sup-
ported by FIPS, or if you suspect a bug in FIPS, make a transcript of your
session using the -d switch and send the file FIPSINFO.DBG along with a
short comment to [e-mail]. Possibly your
problem has already been solved.


14. Credits

FIPS is based on the procedure described by Drew Eckhardt in Linux digest132.
Most of what I know about Harddisk structures comes from the excellent german
book 'Scheibenkleister II' by Claus Brod and Anton Stepper. It is for the
Atari ST, but much of it applies to PCs also.
Information on the Harddisk Interrupts was drawn from Ralf Brown's Interrupt
List. Thanks to Hamish Coleman for some useful info and to Paul Smith for
his good suggestions. Gunnar Hilmarsson suggested the procedure for stacked
drives, and Miguel Alvarez helped me improve the partition ordering. Chetan
Patil, Rand Phares and Eric Jung pointed me at bugs in the program and
documentation. Stefan Andreasen provided important informations about OS/2.
Keith Crews suggested some additions to the documentation concerning the
preparation of the boot disk and new features of DOS 6.x. Dave McCaldon
wrote the code for detecting the OS FIPS is running under. Scott Ellentuch
and Billy Patton provided info about OnTrack Disk Manager.
Thanks to all others who sent me feedback.


Arno Schaefer
[e-mail]