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<!DOCTYPE html>
<html lang="en">
<HEAD>
<meta http-equiv="content-type" content="text/html;charset=utf-8">
<META NAME="GENERATOR" CONTENT="Mozilla/4.05 [en] (Win95; I) [Netscape]">
<META NAME="DESCRIPTION" CONTENT="Partition Manager Help">
<META NAME="AUTHOR" CONTENT="Mikhail Ranish, ranish@intercom.com">
<META NAME="ROBOTS" CONTENT="INDEX,NOFOLLOW">
<TITLE>Partition Manager Help</TITLE>
</HEAD>
<BODY>
<PRE>
Partition Manager Help
What is <A HREF="#part">partition table</A>, <A HREF="#mbr">MBR</A>, <A HREF="#ipl">IPL</A>?
<A HREF="#save">Saving and Restoring MBR</A>
<A HREF="#create">Creating a new partition</A>
<A HREF="#format">Formatting partition</A>, <A HREF="#systems">supported file systems</A>
<A HREF="#os_inst">Things that you should do before installing a new OS</A>
<A HREF="#compact">Compact Boot Manager</A>
<A HREF="#advanced">Advanced Boot Manager</A>
<A HREF="#virus">Virus detection</A> and <A HREF="#hints">hints</A>
<A HREF="#setup_adv_example">Running DOS from the second hard drive</A>
<A HREF="#cmd_line">Command line options</A>
<A HREF="#moreinfo">Links to additional help</A>
</PRE>
<HR>
<A NAME="part">What is partition table?</A>
<PRE>
Partition table is located in the first sector of every hard disk.
It has information about sizes and locations of partitions on the disk.
What is partition? It is a piece of disk space marked to belong to some
operating system. For example, your C: drive resides in the partition
of type <A HREF="#0x0600">BIGDOS</A>.
Most disks have one partition, but some people want to have more
than one operating system on their computers and therefore, have to
divide their disks into different partitions. That's why partition table
also keeps an indicator of the currently 'Active' partition - the one
from which the computer boots.
<A NAME="mbr"></A><A NAME="ipl"></A>
When you turn on your computer BIOS loads into memory the first
sector from hard disk, called MBR (Master Boot Record). In addition to
partition table, this sector contains an IPL (Initial Program Loader) -
a piece of code that searches partition table for an 'Active' record
and loads in memory boot sector of the corresponding operating system.
Standard IPL would simply load a boot sector without any messages
or questions. And this is good if you have only one operating system,
but when you have more then one, you need something more sophisticated.
For example, IPL that comes with this program can ask user at
<A HREF="#ipl_mesg">boot time</A> which operating system he want to boot and
will remember the selection, so that the next time it boots from the
same OS.
Partition table is limited to maximum 4 entries. This program gives
you an option to have up to 31 bootable partitions if you install
<A HREF="#setup_adv">Advanced Boot Manager.</A>
<A HREF="#moreinfo">Links to additional information and help</A>
</PRE>
<HR>
<A NAME="save"></A><A NAME="restore"></A>Saving and Restoring MBR
<PRE>
Saving you MBR is the first thing you have to do before playing
with this program.
First of all create a bootable floppy disk and copy this program
to floppy. Than save your MBR to a file. You can do it
by using S command in interactive mode or by running program from
the command line:
part -s a:\saved.mbr
If something goes wrong, you can always restore the original MBR by
running the command:
part -l a:\saved.mbr
If you are using the same floppy with more than one computer be
careful not to put MBR from one hard disk to another. It will do no
harm, but you may have a few minutes of panic thinking that you have
lost all your files, before you figure out what happend. So, make
sure that you give distinctive names to the files with saved MBRs.
But even if you do load the wrong table it will most likely
become <A HREF="#conflict">RED</A>, because partition settings will conflict
with the current hard disk geometry.
</PRE>
<HR>
<A NAME="active"></A>Selecting active partition
<PRE>
To make partition active you can press SPACE in the interactive
mode or from the command line:
part -p print partition table
part -a n where n is a partition number
If you have installed an IPL then you can press SPACE on the
active partition to make it inactive and when you reboot computer
it will try to boot from the second hard disk, or from a floppy.
</PRE>
<HR>
<A NAME="advanced"></A>Advanced Boot Manager
<PRE>
With Advanced Boot Manager you can have up to 31 bootable
partitions. It keeps its own partition table in the separate space
on the disk.
When you boot the computer the first part of Advanced Boot Manager,
which is located inside MBR tries to read the second part from the disk
and checks its integrity. In case if it was corrupted it promts the user
to boot from A: or hard disk.
After that Advanced Boot Manager <A HREF="#virus">checks for viruses</A>, and then
compares records in MBR with its own partition table. If there were any
changes, the Advanced Boot Manager copies modified records to its own
partition table and advises the user to run part.exe to review them.
Also see <A HREF="#os_inst">notes</A> on installing a new OS.
Then Advanced Boot Manager gives you a menu where you can select
from which partition you want to boot. After you make a choice it copies
the record of the selected partition to MBR table and hides the rest of
the space on the disk.
Advanced Boot Manager keys:
ENTER - boot from the highlighted partition (you can also press 1-9)
ESC - boot from the highlighted partition, but don't remember this
choice for the next time.
A - boot from A and put the highlighted partition in MBR
H - boot from A but hide all partitions on the hard disk,
except the first piece of the unused space which is larger
than 63 sectors. (Good when you install a new OS).
TAB - boot from the next hard drive.
ALT-ENTER - Same as ENTER, but do not put keys into keyboard buffer
if there are any keys specified in the boot menu.
</PRE>
<A NAME="setup_adv"></A>Editing Advanced Boot Manager Menu
<PRE>
For each item in the menu you can specify: (see <A HREF="#setup_adv_example">example</A>)
- Device from which you want to boot (Dev)
C - current disk (on which this menu resides)
D - next hard disk
A - first floppy disk
- Which partition should be made active on this hard disk (0 - for none)
- Row in which this partition should be placed in the MBR. (see <A HREF="#setup_adv_example">example</A>)
- Which partitions show together with the bootable partition.
The choices are: Last, Previous, Next, and Last3 partitions,
including the one from which you boot.
- Whether this menu choice should be password protected (PP)
- The name that you want to see in the menu
- Keystrokes that should be placed in keyboard buffer before booting
this OS. (for exaple, simulating F4 before booting Windows 95 will
make Windows 95 booting the previous version of MS-DOS)
</PRE>
<A NAME="setup_adv_opt"></A> If you press Alt-O you can change boot manager's options:
<PRE>
- Boot menu title
- Enable check for <A HREF="#virus">boot viruses</A>
- Clear screen before drawing the menu
- Timeout (0 forces boot manager to stop and wait for user's input)
- Default partition (overrides remembered "last selected")
- Optional password for Advanced Boot Manager
- Ignore unused partitions, when evaluating "Prev", "Next", "Last"
When password is set it protects booting from floppy (via keys A, H)
and from the second hard disk via TAB. However, you can make a menu line
which will boot from the floppy or the next hard disk, without asking the
password (simply do not enable "PP" - password protected - flag).
</PRE>
<HR>
<A NAME="setup_adv_example"></A>Example of Advanced Boot Manager setup
<PRE>
Suppose that you have two hard disks on the system:
Your new 4.3Gb hard disk And old 340Mb hard disk
1 AdvBootManager 30k 1 DOS FAT-16 340Mb
2 Windows FAT-32 2600M
3 Windows NT NTFS 400M
4 Linux 400M
5 Linux swap 30M
6 DOS Extended 800M
Then Advanced Boot Manager Menu could look like this:
# Dev Partitions Name Keys
1 C 2/* Last Windows 95 N
2 C 2/* Last Windows 95 / Prompt Y <-- "F8 6 Enter"
3 C 3/2 Last Windows NT N
4 C 4/3 Next Linux N
5 C 4/3 Last3 Linux (sees extended) N
6 D 6/* ---- Old MS-DOS (sees ext) N
7 D 0 ---- Old MS-DOS (sees nothing) N
Note: in order to get DOS running from the second hard drive you have
to do the following steps:
- Install Compact or Advanced Boot Manager on the second hard drive
- Go to setup screen for FAT-16 partition and set drive number to 129
- Make sure you don't have any unhidden primary FAT-16/12 partitions
on the first hard drive when you boot from the second.
Also note that Windows NT and Linux will be placed in rows 2 and 3
in the partition table, respectively, while we don't care where will
end up Windows 95.
For Windows NT it is important always to be in the same row, because
it's boot.ini file has syntax like this:
multi(0)disk(0)rdisk(0)partition(2)\WINNT="Windows NT" /basevideo /sos
And it would not be able to find its kernel if we move it to a different
row in the partition table.
</PRE>
<HR>
<A NAME="setup_adv_example2"></A>Another example - preparing for installation of Windows 98 (or another OS)
<PRE>
- Create a bootable floppy and copy Partition Manager to it
- Create and then format partition
- Edit boot menu
Your partitions
1 AdvBootManager 30k
2 Windows FAT-32 1600M <-- This is Windows 95 partition
3 Windows FAT-32 1200M <-- This one was just created and
4 DOS Extended 800M \ formated for Windows 98
Advanced Boot Manager Menu
# Dev Partitions Name Keys
1 C 2/* Last Windows 95 N
2 C 2/* Last Windows 95 / Prompt Y <- "F8 6 Enter"
3 C 3/* Last Windows 98 N
- Save this data to hard disk and to a file on the floppy
- Reboot computer
- In the boot manager menu select "Windows 98" and press A
to boot from a "Windows 98 Setup" floppy
- After installation of Windows 98 run Partition Manager to
review any changes in MBR and <A HREF="#os_inst">reinstall</A> boot manager if
nesessary.
</PRE>
<HR>
<A NAME="compact"></A><A NAME="setup_ipl"></A>Compact Boot Manager
<PRE>
Compact Boot Manager fits in 446 bytes and doesn't need any space
on the disk beyond MBR. It is simply an <A HREF="#ipl">IPL</A>.
When you install it you have 4 options:
- Enable check for <A HREF="#virus">boot viruses</A>
- Prompt's time-out
- Default partition (overrides remembered "last selected")
- Default place to boot from if none of the partitions are active.
The choices are A: and the next hard drive.
Hint: if you set default partition to A then computer will always
boot from A:, if to Tab - from the next hard disk, and when
set to Space - then it will stop and wait for your choice.
</PRE>
<HR>
<A NAME="ipl_mesg"></A>Understanding messages of Compact Boot Manager
<PRE>
Message Description
Press ESC to skip prompt and boot OS
Press SPACE to stop and wait for selection
"Booting from: HD1/1..." Press 1-4 to boot from corresponding partition
"Booting from: HD1/_" Press A to boot from a floppy or TAB to boot
from the next hard drive. Any other key will
resume booting, and will remain in the buffer.
For instance F4, F5, F8, ... (see <A HREF="#hints">hints</A>)
"Writing changes..." IPL is saving your selection into MBR.
"Error!" Error reading disk or empty partition selected.
"Virus !!!" IPL found that one of interrupt vectors doesn't
point to ROM BIOS memory (see <A HREF="#virus">virus protection</A>).
You can press ENTER to resume booting, but it
would be better to shut down the computer and
run antivirus program, after booting from a
clean floppy disk.
</PRE>
<HR>
<A NAME="virus"></A>Virus protection
<PRE>
IPL that comes with this program can detect viruses even before
operating system gets into memory. This is important, because some
<A HREF="#mbr">MBR</A> viruses cannot be detected by antivirus programs that are
loaded after operating system.
Virus detection is implemented by checking 29 interrupt vectors
from int 0h to int 1Ch. They must point to addresses C000:0000h or
higher, where ROM BIOS resides. These interrupts control all vital
functions of the system, such as Timer, Video, Keyboard, and Disk.
If any of the interrupts have been changed it is very likely that a
virus invaded the system. In this case the IPL stops and warns user.
You have a choice to continue booting with virus in memory or rebooting
the system and run antivirus. See <A HREF="#ipl_mesg">IPL messages</A> section.
However, on some systems this method of checking for virusus will
produce false alarms. In this case you can disable virus detection.
<A NAME="hints"></A>
Another way of protection from viruses is to avoid accidental boots
from the floppy drive. With this program you can do that, while still
being able to boot from floppy, when you need it. To do that:
1. Install either Advanced or Compact Boot Manager that comes with
this program.
2. Change boot sequence to C:,A: in the BIOS setup
3. When you need to boot from A: at the <A HREF="#ipl_mesg">boot time</A> press A.
This trick will not only save you from viruses, but will also speed
up your work. It is especially impressive if you have QEMM 8.xx together
with MS-DOS or Windows 95.
Set "BootFloppy:N" option in QEMM's quick boot and add "SWITCHES=/F"
to your CONFIG.SYS file.
Next time, when you reboot QEMM's Quick Boot will skip BIOS memory
test and take you straight to the Compact Boot Manager's prompt where
you will be more comfortable with pressing F4, F5, or F8 ...
</PRE>
<HR>
<A NAME="create"></A>Creating a new partition
<PRE>
To create a new partition find unused record in the partition
table and press INS, then select desired File System type.
After you do that Partition Manager will automatically put values
for cylinders, heads, and sectors.
In most cases you don't need to modify those values. But if you
have in mind your own partitioning scheme you can change them. When
you do that, do start and end partitions on the cylinder (or head)
boundaries. It is not required, but highly recommended. For example,
if your hard disk has 16 heads and 63 sectors per head, you should
start partition on head 0, sector 1 and end on head 15, sector 63.
<A NAME="0xFF00"></A>
If you need to install several operating systems such as MS-DOS,
Windows 95, or Windows NT, and you want to avoid their interference
with each other you may want to hide existing partitions, while
installing operating system into a new one, and unhide them later.
While you are entering numbers partition may turn red. Don't
worry about it until you finish.
<A NAME="conflict"></A>
The red color of the partition means that the settings appear
to be invalid or conflicting with the current disk geometry.
To help you figure out what's wrong I had defined four error codes.
They are shown in red color on the right when you move cursor on the
invalid partition.
mbr: partition overlaps MBR in the first sector of the disk or
extended dos partition.
range: partition have values for cylinder, head, or sector (CHS)
outside of the range of disk or extended dos partition boundaries
or it ends before it begins. Move cursor on the CHS fields to see
the hint with allowed values.
overlapped: two partition are overlapping each other.
inconsistent: this message means that CHS values do not correspond
to starting sector and partition size, which are also stored
in the partition table. Usually this happens if partition table
was damaged or BIOS disk geometry translation has changed since
partition table was last modified. This error will also appear
if you have value 0 for sector (sector must be at least 1).
If the red color appears as soon as you started it may be because
you have changed disk controller or BIOS settings or MBR was corrupted.
If this is the case don't change any values unless you are absolutly
sure what you are doing.
Hint for the professionals: no matter how BIOS represents disk
geometry the relative number of sectors and partition sizes hold.
To fix the problem of inconsistency you have to switch to the LBA mode
by pressing F4, note the size of the partition, change it and then
change it back to the correct size. This will force the program to
recalculate the values in CHS according to the current disk geometry.
However, keep in mind two things: As far as I can tell DOS uses
CHS values to boot and doesn't use starting sector/number of sectors
fields. Instead, it uses field "sectors prior partition" and
"big total number of sectors" from its boot record.
If you had used OnTrack DDO or Ez-Drive you should know that they
skew disk: OnTrack by 63 sectors and Ez-Drive by 1 sector. Therefore
you have to reflect this change in DOS boot records.
</PRE>
<HR>
<A NAME="format"></A>Formatting partition
<PRE>
You can format partitions or just check disk surface for bad sectors
without destroying the data.
To verify any partition press V in interactive mode or run:
part -v n
To format partition press F in interactive mode or run:
part -f n options ...
Format options depend on <A HREF="#systems">file system</A> that you are formatting.
Important notes on formatting DOS partitions
First of all DOS cannot see newly created partition, untill you
reboot computer, because it scans partition table only once.
So if you created and/or formatted a new partition you have to
reboot before you can use it.
If the partition already mounted (you can see it as a DOS drive)
and you formatted partition with different parameters you also have
to reboot computer, because DOS keeps in memory old numbers, and will
most certainly mess up the disk if you will try to write to it
without rebooting.
The other problem is disk caches. Partition Manager flushes them
using SmartDrive v 4.00+ API. Most of the new cache programs, such as
PC-Cache 8.0, NCACHE2, SpeedDrive support it. But if you have any
other cache you should disable it before formatting DOS partitions
or reboot computer after formatting.
The difference in behaviour of part.exe and format.com is that
part formats partitions by number in partition table and format by
letter in DOS device list. Therefore before rebooting you shouldn't
use programs that accesses partitions via DOS, but you can use
programs that writes to partitions bypassing DOS. For example zpart,
which compresses and decompresses entire partitions to and from files.
Limitation: currently this program cannot format logical DOS drives
from the command line - you have to go to the interactive mode.
</PRE>
<HR>
<A NAME="os_inst"></A>Important issues on installation of a new OS
<PRE>
Windows 95 and some other operating systems upon installation
replace your current <A HREF="#ipl">IPL</A> with their own code. If you have
Compact or Advanced boot managers installed on your hard drive you
would not see them at the next boot.
I have worked on this issue. It should not lead to the loss of
data, at least with Windows 95. In the worst case you just would have
to run part.exe and reinstall boot manager. But to ensure that nothing
will be lost do the following steps before installing new OS:
- Create a bootable floppy and copy Partition Manager on it.
- Run Partition Manager and create partition for the new OS.
- If possible format it using Partition Manager.
- In Advanced Boot Manager edit boot menu (see <A HREF="#setup_adv_example2">example</A>)
- Save Partition Manager's data to the floppy.
- Reboot computer and install a new OS
If MBR will be modified by OS installer review the changes and
reinstall boot manager. (Press F2 in order to save MBR and install
Advanced Boot Manager executable code to disk).
</PRE>
<HR>
<A NAME="systems"></A>Supported file systems
<PRE>
<A HREF="#0x0000">Unused partition</A>
<A HREF="#0x0100">Classical MS-DOS file systems</A>
<A HREF="#0x0B00">Windows 95 FAT-32 file system</A>
<A HREF="#0x0500">Extended DOS partition</A>
<A HREF="#make_primary">Making logical drives bootable</A>
</PRE>
<HR>
<A NAME="0x0000"></A>Unused partition
<PRE>
This simply indicates that entry in partition table is available.
It doesn't tell anything about free space on disk. You have to figure
out that yourself.
However if you specify starting and ending locations of partition
with type "Unused" Partition Manager will let you format and verify
the disk space.
Format takes two options: "/destructive" or "/clean". First one
performes low level disk format, second one fills disk space with
zeros.
</PRE>
<HR>
<A NAME="setup_fat"></A><A NAME="0x0100"></A><A NAME="0x0400"></A><A NAME="0x0600"><A NAME="0x1100"></A><A NAME="0x1400"></A><A NAME="0x1600"></A>Classical MS-DOS file systems
<PRE>
0x01, "DOS FAT-12"
0x04, "DOS FAT-16 (under 32M)"
0x06, "BIGDOS FAT-16 (over 32M)"
All file systems have the same structure:
[Boot Sector]
First copy of FAT]
[Second copy of FAT]
[Root Directory]
[Cluster 2]
[Cluster 3]
[Cluster 4]
...
Boot sector, FATs, Root Directory, and clusters have fixed sizes,
which you can set only when you are formatting the disk.
Space for all subdirectories and files is allocated by clusters.
If cluster size is 8 sectors = 4,096 bytes, when you create file with
size of 1 byte it will get entire 4,096 bytes cluster.
There is an entry in FAT (File Allocation Table) for each cluster,
which tells if cluster is free, allocated, or damaged. Therefore size
of the FAT determines maximum number of clusters.
FAT-12 file system is limited to 4084 clusters. It is used on the
floppy disks, but you can also use it on a small hard disk partition.
FAT-16 was used on early hard disks. Original version could have
up to 65,000 clusters on partitions up to 32M.
BIGDOS FAT-16 which was released with DOS 3.31 doesn't have 32M
limitation and can be as large as 2G. For backward compartibility
all DOS versions later than 3.31 will accept both FAT-12 and FAT-16
file systems in the BIGDOS partition.
This program includes format utility which formats all three file
system types. It has the following options:
part -f n [/quick | /destructive] [/l:volume_label]
[/c:sect_per_cluster] [/x:max_num_sect | /x:disk]
If you specify "quick" option, the program will assume that your
hard disk doesn't have any bad sectors. You can verify disk once, and
if it doesn't have bad sectors you can then use quick format.
If you don't specify cluster size it will be selected automatically
depending on partition size from 4 sectors and up. Here is the table
for BIGDOS FAT-16 file system:
Cluster size Maximum partition size
1 sector 512 bytes 32M
* 2 sectors 1,024 bytes 64M recommended
* 4 sectors 2,048 bytes 128M cluster sizes
* 8 sectors 4,096 bytes 256M are marked
* 16 sectors 8,192 bytes 512M with '*'
* 32 sectors 16,384 bytes 1G
* 64 sectors 32,768 bytes 2G
128 sectors 65,536 bytes 4G
Although you can format disk with all those cluster sizes it's not
recomended to use very small or very large values. Many programs have
weird bugs with that. For example, SCANDISK will freeze if cluster
size is 128, while Norton Disk Doctor seems to work without problems.
By specifying max_num_sect parameter you can reserve space in FAT
for the future expansion of the partition. If you type "/x:disk"
(exactly as it is written) format will make FATs large enough so that
you can expand you partition to entire disk.
You can make FAT partition smaller (shrink them). To do that run
some disk defragmentation utility (like DEFRAG.EXE). Then go to setup
screen inside part.exe. One of the lines will show the minimum
partition size, based on the last cluster occupied by data. The value
should be equal to sum of the file and directory sizes on your disk.
If it is greater it means, that some hidden files were not moved by
the defragmentation utility. You have to find those files (for example
Norton Speed Disk will show their names), remove system and hidden
attributes and run disk defragmenter again. But be careful with moving
them, because some programs may use absolute file locations for their
illigal installation checks.
</PRE>
<HR>
<A NAME="setup_fat32"></A><A NAME="0x0B00"></A><A NAME="0x0C00"></A><A NAME="0x1B00"></A><A NAME="0x1C00"></A>Windows 95 FAT-32 file systems
<PRE>
0x0B, "FAT-32"
0x0C, "FAT-32 LBA"
This file system was designed to support disks larger than 2G, which
was the limit for FAT-16 file system. FAT-32 partition can be as large
as 2T (2,048G).
It has the following structure:
[Boot Record (3 sectors)]
[Backup Copy of Boot Record]
[First copy of FAT]
[Second copy of FAT]
[Cluster 2]
[Cluster 3]
[Cluster 4]
...
Root directory on FAT-32 treated as an ordinary directory, and can
be located anywhere on the disk and doesn't have predefined fixed size
(unlike FAT-16).
Options for formatting FAT-32 file system are similar to FAT-16
options:
part -f n [/quick | /destructive] [/l:volume_label]
Strategy for resizing FAT-32 partition is also similar to one for
FAT-16:
- Run defragmenter utility on the FAT-32 partition
- Change partition size in the partition table
- Enter setup screen and make same changes there
(make sure they are valid - otherwise they will turn red)
- Reboot computer and run scandisk to check that everything
is ok and also to reset amount of free space.
</PRE>
<HR>
<A NAME="0x0500"></A><A NAME="0x1500"></A><A NAME="extended"></A>Extended DOS partition
<PRE>
Partiton table has space for only four records. To have more than
four partitions DOS uses Extended DOS partition scheme. This scheme
allows you to have as much as 23 DOS volumes on one physical drive.
Unfortunately, native DOS's program FDISK imposes another limitation
that you cannot have more than one primary (bootable) MS-DOS partition
on the hard disk. The truth is you CAN have more than one. The problem
is that MS-DOS's FDISK refuses to create second one for you.
If you run FDISK it will create one primary partition and then will
mark the rest of the space as an Extended partition. The first sector
of the Extended partition is called EMBR (Extended MBR). It has the
same structure as MBR. Inside of each Extended partition you can have
one FAT (or NTFS) partition, called logical drive, and another Extended
partition. For some unknown reason relative sectors of inner extended
partitions are calculated from the beginning of the outermost partition,
while relative sectors of FAT partitions are from the beginning of the
enclosing extended partition.
Here is an example:
HD 520 Mb
---------------------------------------------------
Primary FAT-16 120Mb [ C: 120Mb ]
Extended DOS 300Mb -----------------------------
FAT-16 100Mb [ D: 100Mb ]
ExtDOS 200Mb ---------------
FAT-16 200Mb [ E: 200Mb ]
---------------
-----------------------------
Linux 100Mb [ / 100Mb ]
---------------------------------------------------
Note that the order of partitions on the disk also matters. FAT
partition must go first. And the extended partition must follow.
Hint: in the Partition Manager you can use PgUp and PgDn to jump
between EMBR levels.
You cannot boot from extended partition, nor from any logical drive
inside of it. If you try it, the system would simply hang, because its
boot record unlike other file systems doesn't have any loader code. It
has only zeros. You can install a "non bootable" dummy boot record,
which instead of crashing will display a message:
Extended DOS partition is not bootable.
Press any key to reboot...
<A NAME="make_primary"></A>Making logical drives bootable
As I mentioned before, you cannot boot from Extended partition or
from any logical drive contained in it. But what if you need? The
solution is simple. All you have to do is to move the record that
describs logical drive from the EMBR to the primary MBR, and adjust
size of the Extended partition. Then you have to set the correct
number of "sectors prior to partition" in the DOS boot sector,
whose value is used to load system files. And finally you have to
run sys.com to install system files on disk.
Lets see what we can do with <A HREF="#extended">our example</A>.
Variant 1.
Notice that size of the extended partition was changed and second
extended partition is gone.
HD 520 Mb
---------------------------------------------------
Primary FAT-16 120Mb [ C: 120Mb ]
Extended DOS 100Mb -----------------------------
FAT-16 100Mb [ D: 100Mb ]
-----------------------------
Primary FAT-16 200Mb [ E: 200Mb ]
Linux 100Mb [ / 100Mb ]
---------------------------------------------------
Variant 2.
Here we just moved both records from extended partition to the MBR.
HD 520 Mb
---------------------------------------------------
Primary FAT-16 120Mb [ C: 120Mb ]
Primary FAT-16 100Mb [ D: 100Mb ]
Extended DOS 200Mb -----------------------------
FAT-16 200Mb [ E: 200Mb ]
-----------------------------
Linux 100Mb [ / 100Mb ]
---------------------------------------------------
Variant 3.
HD 520 Mb
---------------------------------------------------
Primary FAT-16 120Mb [ C: 120Mb ]
Primary FAT-16 100Mb [ D: 100Mb ]
Primary FAT-16 200Mb [ E: 200Mb ]
Linux 100Mb [ / 100Mb ]
---------------------------------------------------
</PRE>
<HR>
<A NAME="cmd_line"></A>Command line options
<PRE>
Usage: part [-q] [-d disk] [-command ...]
part - Interactive mode
part -i - Print IDE disk info
part -p - Print partition table
part -p -r - Print info recursively
part -a n - Activate n-th partition
part -v n - Verify n-th partition
part -f n ... - Format n-th partition
part -s file - Save MBR to file
part -l file - Load MBR from file
part -c file - Compare MBR with file
part -Reboot - Reboot computer
The program returns exit code 0 if there was no errors and/or
compared objects had no differences (1 is returned otherwise).
</PRE>
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<A NAME="moreinfo"></A>
<PRE>
Additional information and help resources
<A HREF="https://github.com/boeckmann/ranish">Partition Manager Repository</A>
</PRE>
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