1 reply to this topic

[MarkD]

So I have spent way too many hours trying to get the following environment to work: USB key partioned into multiple primary and logical partitions - each with different OS - using GRUB4Dos as primary bootloader. Here's what I have tried (and failed):

- created partitions using gparted (also tried Windows Computer Management tool)
- installed Grub4dos in MBR using Grubinst from DOS window
- boots fine to G4D main menu
- USB key is also visible in both WinXP and Ubuntu - all partitions visible in Ubuntu, only 1st in WinXP (expected behavior)
- try to view USB partitions in gparted -- fails due to error - cannot read partition table

It seems that Grubinst installs a non-standard boot record, and this is hosing gparted. While I could probably live with this anomaly, it creates the obvious problem that I cannot adjust/repartition/reformat the drive in future.

I have researched G4D extensively, and it seems to the best choice to load various OS's, and lots of people are using it, but why can I not get the MBR installed properly. I have tested against various USB keys and USB hard drives -- same error every time.

Any help would be greatly appreciated -- I am probably doing something wrong that is very basic, but I cannot figure this one out.

Mark

[was_jaclaz]

That's actually most probably the culprit (about the gparted problem):

- installed Grub4dos in MBR using Grubinst from DOS window

You actually do not need to install grub4dos to MBR+hidden sectors.

- USB key is also visible in both WinXP and Ubuntu - all partitions visible in Ubuntu, only 1st in WinXP (expected behavior)

Easily fixable by installing either the Hitachi Microdrive Filter cfadisk.sys or the dummydisk.sys by Anton Bassov.

It seems that Grubinst installs a non-standard boot record, and this is hosing gparted. While I could probably live with this anomaly, it creates the obvious problem that I cannot adjust/repartition/reformat the drive in future.

Actually grubinst, that can be substituted by this Win32 installer:
http://www.disklessa...hp?name=product
http://www.disklessa...-bin-w32-19.zip
should NOT touch the bootsector (i.e. first sector of any partition) but surely it overwrites the MBR (i.e. first sector of the whole drive) and a number of the following hidden sectors (depending on version of grub4dos).

Also, please state which exact version of grub4dos you are using, when in doubt always use latest "nightbuild" and if it sdoes not work revert to latest previous "stable" version, see here:
http://www.boot-land...?...opic=14&hl=

The "safe" way and totally compatible way to install grub4dos is actually NOT to install it, but rather to format First Primary Active Partition of the stick normally with 2K/XP, then have in the ROOT directory:
NTLDR
NTDETECT.COM
grldr
menu.lst
BOOT.INI with an additional entry as follows:

C:\grldr="Grub4dos"

(if you are booting a PE of some kind you can chainload SETUPLDR.BIN directly from inside it's \I386 or \minint directory)

This way the MBR will be the standard 2K/XP/2003 one (maybe the "hacked" HP USB utility one), all hidden sectors will be 00's and the bootsector of first partition wil be the normal (FAT,FAT32 or NTFS one), so everything will be compatible with everything.

jaclaz