The Unsorted BBS Collection/thegreatunsorted.tar/thegreatunsorted/misc/fips.doc

Text File | 1994-01-11 | 20KB | 448 lines

                  Welcome to FIPS
    The First nondestructive Interactive Partition Splitting program

                 Version 0.9 beta
                 November 7, 1993

             Copyright 1993 by Arno Schaefer


0. What you need to use FIPS
1. Introduction
2. Safety
3. Restrictions
4. Before you start
5. Use with Stacker/SuperStor/Doublespace
6. Using FIPS
7. After splitting the partition
8. Commandline Switches
9. Troubleshooting
10. 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 1, 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. Suitable programs are Norton's Speedisk, PCTools' Compress,
or the Shareware programs ORG, DOG or SAFPAK (available by anonymous FTP from
any simtel mirror in the <msdos.dskutl> directory). I did not test these how-
ever, so don't blame me if they don't work for you.
You may also want to use a program like Norton Disk Doctor 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 should also work under DR-DOS (never tested it, though). It has been
reported to work with DOS 6.0.

Don't use FIPS in multitasking environments like OS/2, Desqview, Windows or
the Linux DOS-Emulator. I don't know what will happen, but I would not like
to take any chances. FIPS does not (yet ?) attempt to detect these, so be
careful! Better boot from a DOS disk and then run FIPS.


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 diskettes (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. 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 4).
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.


3. Restrictions

FIPS will only work with Hard Disk BIOSes that use interrupt 13h for low
level harddisk access. I don't know if there exist others, but if you happen
to have one (large SCSI disks, perhaps?), FIPS will most certainly not find
any meaningful data and thus will exit without attempting to write anything.

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 did not hear of formatting programs that use this possibility.
If anybody can tell me anything about it, I may incorporate this in a later
release.

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.

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.

4. Before you start

Run CHKDSK on the partition you want to split. If you have Norton Disk Doctor
or something similar, you may use it also. Make sure there remain no 'dead'
clusters on the disk.
Prepare a bootable floppy disk in drive A:. If you need a device driver to
access your harddisk, install it on the floppy (see your Hard Disk Controller
manual for details). Copy the file RESTORRB.EXE to this disk. When starting
FIPS, you will be given the opportunity to write backup copies of your root-
and bootsector 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 infor-
mation by booting from the floppy and running RESTORRB.

In addition to this 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 disks 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 still complains about the new partition not being empty after defrag-
mentation, this may mean

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 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 (this was corrected in ver-
sion 0.2.2). You just need to edit your /etc/fstab file if you mount your DOS
partition on bootup.


5. 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 (I don't know if this is possible),
FIPS will complain about the partition not being empty. You may need to add
the following steps. Attention: I can not guarantee that this will not cor-
rupt the compression scheme, see your manual for details. It seems to work
with Stacker, but I have no reports about the other programs.

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.


6. Using FIPS

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 detect you hard disks, if you have more than one, it will
ask you which one you want to work on.
FIPS then reads the rootsector of the hard disk and display 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, you may now enter on which cylinder the new par-
tition should start. The calculation is the following: The size of one cylin-
der in KB is: number of heads * number of sectors per track / 2 (in the above
case 504 KByte). The new starting cylinder is: start cylinder of partition
(from the partition table) + (desired size of reduced partition in KB / size
of one cylinder in KB).

Example:
If I want to reduce partition 2 in the above example to 50 MB, I calculate:
0 + ((50 * 1024) / 504) = 101. This is the number I would enter, which would
result in a 50 MB and a new 18 MB partition.

FIPS will look if the space for the new partition is empty, if not it will
stop.

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.


7. 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 (btw. since the
new partition does not yet contain any data, you could as well use fdisk
to delete it and create two new ones).


8. Commandline Switches

Since version 0.2 there are commandline switches to use FIPS non-interactively
and to override some of the error messages. If you prefer the DOS style, you
may use '/' instead of '-' as the switch character. The switches may be arbi-
trarily combined. Type 'FIPS -help' to get a list of the switches.
Here is a more detailed explanation:

-q or -quiet : quiet mode

The program only displays the prompts for input, nothing else. If you have
selected drive,partition, start cylinder and save/nosave on the commandline,
the program will run completely silent. Attention: no write confirmation is
requested. Like this, you can use the program in a batch file (I don't think
anybody will ever need this feature - you don't change your partition size
every day - but here it is :-). Perhaps it could be useful in a network
environment with many identical workstations.

-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.

-s+       : save rootsector and bootsector to floppy without prompting
-s-       : do not save rootsector and bootsector to floppy

These switches skip the question if you want to save the root- and bootsector.
Insert a floppy disk before starting FIPS when using -s+.

-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 new 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.


9. Troubleshooting

FIPS is still very experimental, and 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 8).
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.


10. 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. Thanks to all others who sent me feedback.


Arno Schaefer
[e-mail]