3 replies to this topic

[halikus]

Like the title says, is there any EFI bootloader that has the ability to boot a Windows ISO in EFI mode?  I have seen references to Grub2 and rEFInd booting loopback linux isos, but nothing regarding a Windows ISO. 

 

Also, in Grub2 EFI both these commands will take me to a grub4dos cmd prompt, but won't find the lst file.  I don't think so, but maybe there is a 1% chance to get an iso to load by adding to the commands.

 

menuentry 'Grub4dos efi'{
linux /efi/grub/grub.exe --config-file="/efi/grub/menu.lst"
}
 
menuentry "GRUB4DOS" {
linux /boot/grub/grub.exe --config-file=/boot/grub/menu.lst
}

 

 

 

Also, while i started a thread, in g4d, is there a way to distinguish USBs from HDDs with a cat command or something?  I'm terrible with offsets.

 

[Wonko the Sane]

Well, grub4dos will "cease to work" as soon as it "hits" instead of a BIOS an EFI/UEFI.

This is "by design".

Steve6375 posted here:

http://www.911cd.net...ndpost&p=174076

how he is going to have a look at some of the alternatives, but it will surely take some time.

In the above thread of 911 there is some more info on the issues.

 

What do you mean "distinguish" USB from HDD?

I don't think that there is anything like that (I mean "connection bus distinction"), wouldn't it be - in order to solve the whatever actual problem - to use the "traditional" "tag file" or "UUID" (or Disk Signature) to identify a given disk?

 

Wonko

[halikus]

Thanks.  I realize i could use UUID, i can distinguish between cd and usb\hdd, but i would like to be able to check an HDD if it is internal or an external flash drive.  Its for if i run grub4dos off an internal HDD, as the odd trick like hooking the (hd0) (hd1) doesn't work whereas it does from USB.  Another example would be loading Win isos from an internal HDD with firadisk; you can't write to the autounattend or setisoname.cmd.  Its just another variable i can play with if something doesn't work.

[Wonko the Sane]

As said, besides UUID and Disk Signature (that will only identify a given device) you can use a tag file.

 

Just drop a 0 byte .txt file *like* I_am_USB.txt in the root of all your USB devices and be done with it.

 

When it comes to USB sticks (of course NOT USB hard disks), a quick and dirty way is to check their size.

 

The probability of any PC having an internal hard disk device equal or smaller than - say - 32 Gb AND a USB stick equal or larger than the same 32 Gb are pretty much low.

(or maybe 16 or 64 Gb, it depends on the machines and sticks you have).

 

As well, if you happen to have grub4dos installed to the MBR of USB devices AND on the MBR of internal hard disks, you can adopt a "strategy" of using one of the otherwise unused flags ("control bytes") in the grldr.mbr which is copied to MBR and first few hidden sectors.

Just leave as default (say) bytes @04h to 0x3920 (Space) on all the "normal" installs on internal hard disks and change them to *something* else on all the "special" installs on USB. 

 

Or modify the embedded menu.lst in grldr (again only on the USB installs).

 

Wonko