A Windows XP help forum. PCbanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » PCbanter forum » Microsoft Windows XP » Hardware and Windows XP
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

will FIXMBR lose track of my data partition?



 
 
Thread Tools Display Modes
  #1  
Old November 19th 04, 11:59 PM
Gordon Airporte
external usenet poster
 
Posts: n/a
Default will FIXMBR lose track of my data partition?

I have a drive with an NTFS primary partition with windows installed,
and a FAT32 data partition. Currently GRUB is installed in the MBR so I
can access Linux on a second harddrive. I want to move the Linux drive
out, which means I'll be able to let Windows handle the booting.
If I run fixmbr on the windows/data drive, will it lose track of the
data partition, or will it work perfectly so I can boot windows directly
and see everything on the disk?
I think it will, but this always makes me nervous, so I'm checking first :-)
Ads
  #2  
Old November 20th 04, 12:37 AM
Pegasus \(MVP\)
external usenet poster
 
Posts: n/a
Default will FIXMBR lose track of my data partition?


"Gordon Airporte" wrote in message
...
I have a drive with an NTFS primary partition with windows installed,
and a FAT32 data partition. Currently GRUB is installed in the MBR so I
can access Linux on a second harddrive. I want to move the Linux drive
out, which means I'll be able to let Windows handle the booting.
If I run fixmbr on the windows/data drive, will it lose track of the
data partition, or will it work perfectly so I can boot windows directly
and see everything on the disk?
I think it will, but this always makes me nervous, so I'm checking first

:-)

The command fixmbr will restore the standard MBR. It will not
affect your partitions . . . unless your disk uses a proprietary
partition scheme (e.g. OnTrack) or unless your MBR is infected
with a virus.

Since it appears that you already back up your important files
on a weekly basis, you have little to fear.


  #3  
Old November 20th 04, 01:50 AM
Vanguard
external usenet poster
 
Posts: n/a
Default will FIXMBR lose track of my data partition?

"Gordon Airporte" wrote in message
...
I have a drive with an NTFS primary partition with windows installed,
and a FAT32 data partition. Currently GRUB is installed in the MBR so I
can access Linux on a second harddrive. I want to move the Linux drive
out, which means I'll be able to let Windows handle the booting.
If I run fixmbr on the windows/data drive, will it lose track of the
data partition, or will it work perfectly so I can boot windows
directly and see everything on the disk?
I think it will, but this always makes me nervous, so I'm checking
first :-)



FIXMBR (or "FDISK /MBR" for DOS) will write only into the bootstrap
program area (first 460 bytes) of the MBR (master boot record, and which
is not in any partition). It does NOT write the entire MBR (sector 0).
That means the partition table, wherever it is located in the MBR, is
untouched by these utilities. Only the bootstrap program area gets
overwritten to place a standard bootstrap program there. The standard
bootstrap program is hardcoded to expect the partition table to start at
a specific byte offset within the MBR and to be organized in a specific
structure.

If the MBR bootstrap got infected with a virus then the virus might have
moved the partition table or used a different structure. That means the
standard bootstrap program will still try to read from the standard
location for the partition table (which is now wrong because the virus
moved it) using the standard structure (which the virus might have
changed). I don't know if multiboot managers also alter the standard
offset for the partition table or its structure, but I would doubt it.
If a multiboot manager provides more features than available with the
standard bootstrap program, like allowing more than 4 primary
partitions, booting from a partition on a drive physically separate from
the partition table, then it might use the rest of track 0 for an
"extended" partition table and may even occupy the unused track 0 for
the remainder of its program code rather than requiring that code reside
in some partition.

You might want to save an image of your partitions so you can restore
them if the partition table gets screwed up (or the standard bootstrap
program cannot use the partition table or find it). Then you could
delete the partitions, recreate them (so the partition table and its
structure are at the standard offset and in the standard structure), and
then restore the image(s) to the partition(s). There are utilities
around that will let you save and restore the MBR (and can separate the
bootstrap program area from the partition table) but you'll have to know
what you are doing, especially if you screw up and end up having to use
a partition editor to fix the partition table.

If you've been infected with a bootstrap virus, using FIXMBR or "FDISK
/MBR" can result in losing your partitions. I don't know how GRUB
works. If it only resides wholly in the 460-byte bootstrap area of the
MBR and doesn't modify the offset or structure of the partition table
then there should be no problem in stepping on the 460-byte bootstrap
program area in the MBR to put a different [standard] bootstrap program
there. You might want to ask your Linux community what GRUB touches in
the MBR.

--
__________________________________________________ _______________
******** Post replies to newsgroup - Share with others ********
Email: lh_811newsATyahooDOTcom and append "=NEWS=" to Subject.
__________________________________________________ _______________


  #4  
Old November 20th 04, 03:07 AM
Gordon Airporte
external usenet poster
 
Posts: n/a
Default will FIXMBR lose track of my data partition?

Thanks for responding guys - it worked just fine. This is one topic
where it's very hard to turn up the information you want since any web
search on partitions and such turns up a million hits. The MS pages
about fixmbr weren't any help either, I'm afraid.
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is Off
HTML code is Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Data partition not accessible Robert Neville Networking and the Internet with Windows XP 3 October 8th 04 09:52 AM
Format the HDD without deleting the data, as in FAT32/NTFS Eric Wang Hardware and Windows XP 2 October 4th 04 07:05 PM
Two "expert" issues I must solve before upgading Jeff W New Users to Windows XP 29 September 12th 04 03:38 PM
partition magic 8.0 DAVE MC CABE Performance and Maintainance of XP 5 July 29th 04 12:58 PM






All times are GMT +1. The time now is 05:59 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 PCbanter.
The comments are property of their posters.