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kn2user
12-06-2004, 07:32 PM
If I use QTPart to partition an fat32 drive, what is the risk of losing my data?
I have read that before partitioning, you should back your data. I am new to partitioning so I am not sure what happens when a drive is partition does it erease everything on the drive or not. Is it possible to partition without losing your data. Thanks.

firebyrd10
12-06-2004, 09:20 PM
If I use QTPart to partition an fat32 drive, what is the risk of losing my data?
I have read that before partitioning, you should back your data. I am new to partitioning so I am not sure what happens when a drive is partition does it erease everything on the drive or not. Is it possible to partition without losing your data. Thanks.

The parted libary that qtparted uses is stable and about the same quality as commerical software. While there is always a chance, qtparted will not erase your data unless you tell it to resize or reformat. (All clearly marked)

CrashedAgain
12-06-2004, 10:50 PM
I have used QTparted to resize (but not reformat!) vfat partitions without loss of data. It may kill a windows operating system on a vfat partition, however because every windows version since winME writes some data to the last sector of the partition & this gets damaged.
Backup is always wise, however.

jjmac
12-06-2004, 11:48 PM
kn2user wrote ...

>>
If I use QTPart to partition an fat32 drive, what
is the risk of losing my data?
>>

Partitioning is a fairly straight forward process,
but it's not trivial. It just needs to be approched
with a little common sense ...


Backing up is always a good idea, the main risk
involves such things as power outages occurring
half way through a crucial stage, and the actions
of the person themselves.

So, what is the risk ... as long as you go about
things properly and are familiar with the program
your going to use, them probably quite low. Read
the associated docs



>>
I have read that before partitioning, you
should back your data.
>>

Good advice, with out a back up, restoration is
more difficult, no?.



>>
I am new to partitioning so I am not sure what
happens when a drive is partition does it erase
everything on the drive or not.
>>

No, it doesn't "erase" anything, but it changes
the way the system maps to the drive.

The MBR has a 64 byte area starting at 0x1BE, which
contains 4 16 byte records. These
4 records basically
describe the sector number where a
partition starts,
and it's size in sectors. Plus windows' brain-dead
geometry scheme :roll:

Simply put, the file system on that partition will
map to it's files as offsets from that start.

So if you were to alter the start sector for a
partition, or resize it in such a way as to over
extend the start of another, it screws that whole
mapping scheme up. The files are still there,
but somewhat inaccessible.

Recovery is possible, but can involve a lot
of friggin around.


>>
Is it possible to partition without losing your data.
>>

Yes, by taking appropriate steps. Read the
documentation associated with the tool your
going to use, and familiarise yourself first.

The tools i know of won't commit their changes until
you command it to "write" those changes. So
if there is anything your not sure of during the
process, just bail out !, ... then try it again later.

Write your schematic down on paper, use a calculator
to work out the sector count/sizes. Don't try to do
it all on the fly while your actually using
the tool.

In my opinion, one doesn't decide
on what one wants
to do while using a partitioning tool. Those
decisions are made before hand. The tool is just
used to actually do it. And to extract the
existing state of course.

NB:

Make a copy of your existing MBR on a floppy before
you commit any changes. If things do fu*k up,
then you can restore the original via that. And
by setting the bios to boot off the floppy, it
should double as a boot disk as well.

If your unsure how to go about that, look
into "rawrite" (sic) for windows or better (of course) ...

In Linux ...

dd if=/dev/zero of=/dev/fd0
bs=1024 count=1440

dd if=/dev/hda of=/dev/fd0
bs=512 count=1

And check to see if that will boot for you first.

If the partitioning dose fail and you can't get
in, boot off that, then just do ...

dd if=/dev/fd0 of=/dev/hda
bs=512 count=1

And you'll have your MBR back where it started.

The original table is always better than no table, no ? :)

jm

stuart_b
12-07-2004, 12:42 AM
"If I use QTPart to partition an fat32 drive, what is the risk of losing my data? I have read that before partitioning, you should back your data."

When partitioning with a nondestructive tool (Partition Magic, QTParted) it is a good idea to back up your data, because there is always the possibility of an accident. When using fdisk or cfdisk, you of course need to back up your data because that's the only way you will still have it.

"...what happens when a drive is partition(ed) does it erase everything on the drive or not. Is it possible to partition without losing your data."

Partition Magic, QTParted, and similar programs can resize partitions without erasing data. Not so with fdisk. Corollary is the fact that fdisk (and I will point out that is the name for equivalent programs in lots of OSs) rarely messes up the partition table

kn2user
12-07-2004, 06:01 PM
Ok thanks for the info everyone.