I need clarification of Bootable Disk settings

[DAJulin]

I need clarification of Section 3.3.2.3.4 Bootable Disk settings.

 

First and foremost I want to say that, in general, the documentation, tutorials, and guides are exceptional. There does seem to be a tendency to assume the audience is of direct peer quality, or close.  On many occasions it taxes the critical thinking and comprehension, even those of us with IQ’s in the 99 percentile.  This subject matter is not my forte, therefore I dabble, and sometimes dribble due to this, all from necessity.

 

A few things that are not explained in the guides or found in the forums (at least I haven’t found relevance after looking for days). The article and related articles: How to create a Windows Vista / 7 / 8 installation disc (bootable) using ImgBurn, are the only things I have to go on. They don’t cover my needs or questions sufficiently.

 

1. When creating a bootable disk the Platform ID is not explained. I understand what 80x86 means, and Power PC is, well, they might still be out there, and UEFI is the new-new ride. My question comes from trying to create a bootable OS DVD that contains multiple operating systems in both X86 and X64 versions. How do you make something like that – or does it matter from a BIOS or UEFI standpoint? I guess here, since there are no multiple options – you use the base machine “type”. Is this true?

 

1. The “Patch Boot Information Table” is not explained anywhere except in the most vague of terms and only superficially. Only something about boot files larger than 1 MB.  Under what condition would a boot table become larger than 1 MB?  Is this to enable chain loading of the MBR into BIO’s?

 

1. The “Extract Boot Image” is also not explained. I am guessing it copies the image from an existing image like the one already used on your C: drive, or one you were able to copy from another system. A little more detail would be nice.  Is the boot image different between 32 and 64 bit machines? I would think not – not for an OS install disk, even with X86 and X64 options, but what does an oilseed engineer know?

 

1. “Load Segment” is not discussed, there is only, “I get mine from the ImgBurn log”. Really vague.  What is the significance of this value?

 

Granted – you’re not here to give massive lectures on the finer points of computer science or software engineering.  I’d like to be able to follow directions on using a complicated piece of software and learn along the way – not be given a complicated tool with part of the instructions, and told to fix the reactor (I think they did that with Fukushima) –Ops… Crap!  You get my point…

 

– Thank you.

[LIGHTNING UK!]

Unless you specifically want a UEFI bootable disc (where you'd need a UEFI compatible board to actually boot it), stick with the previously forced option of '80x86' (meaning normal BIOS board). The guides don't cover UEFI (I don't have a compatible board).

 

'Patch Boot Information Table' is for Linux type boot discs (isolinux). When burning such discs, there's a boot information table in the boot image that has to be patched with offsets/locations of certain things (for the specific disc you're building) or the disc won't work. Google returns a fair bit of info on the 'boot information table' - here's one page talking a bit about it.

 

http://littlesvr.ca/isomaster/eltoritosuppl.php

 

Extract boot image does exactly what it says on the tin. It extracts boot images from existing media. So if you put in a bootable OS disc, you could extract the boot image from it and use it on the new one you're building. Not that I've ever compared boot images from pure x86 or x64 discs, but I'd assume they're the same. Unless the people that supplied your PC copied the entire contents of the Windows Vista/7/8 OS install disc to a folder on your drive, I doubt you'd find a file suitable for use as a boot image on a CD/DVD.

 

I believe 'Load Segment' is to do with where the 'Sectors To Load' worth of data from the boot image gets put in memory. The BIOS or whatever then runs whatever's there and fingers crossed, the disc boots and does whatever it's meant to do. The 'El Torito' specs might give you more info on that.

[jds]

Thanks Lightning for such a great tool and for your great support!

Sorry to dig up such an old post, but I was seeking answers to a couple of the same questions, so glad that after some careful reading (including the URL you linked), things slowly became clearer for me. Thank you!

Just a suggestion, which you are free to ignore, would be to make the following minor text changes under the Bootable Disc tab :
Patch Boot Information Table -> Patch Boot Information Table (isolinux)
Extract Boot Image -> Extract a Boot Image

This would make it a little more obvious what these two items are, and whether they're relevant. So in my case, it would then be clear that I didn't need the Patch Boot Information Table option, and that the Extract Boot Image selection wasn't asking for some kind of image file, but was a little tool to create such a file (presumably to use in the Boot Image selection above).

Joe.