Side Orders
Before we go further, I would like to bring you some side orders. I have seen people who have obtained ISO CD-Image of a Bootable CD, they can easily extract all files/dirctories onto hard-drive with isobuster, winimage or daemon tools and make changes to it. But when they come to the burning time, they do not find a proper boot-image to burn the CD Bootable. But the correct boot-image is already right there in your original ISO, can we locate it in the ISO and then take it out? The answer is YES, but with proper tools (freewares): /http://members.rogers.com/khayftp1/mkbootcd.exe and /http://members.rogers.com/khayftp1/dd.exe)
Now you have got the tools, let us use the ISO we have just generated (E:CORP2IN1.ISO, Bootable CD Image) to learn how the boot-image can be located and extracted. Ready? Let's go:
In DOS Window, Enter the following command to locate the boot-image:
mkbootcd E:CORP2IN1.ISO
This is the output from mkbootcd:
mkbootcd - make bootable CD image(El Torito specification)
30-Mar-98
gigo@yk.rim.or.jp|imaizumi@nisiq.net V1.02
21-May-98 *BETA* Joliet Extensions
petry@rbg.informatik.tu-darmstadt.de
26-Oct-00 fix/eltorito emulator support by Bart Lagerweij,
bart@nu2.nu V1.02c
== Boot Record Volume Descriptor ==
Indicator:0
Identifier:'CD001'
Version:1
BSIdentifier:'EL TORITO SPECIFICATION'
BootCatLbn:0x00000013(Loc:0x00009800)
*Warnning - Some Garbage in stab1.
== Validation Entry ==
HeaderID:1
PlatformID:0x00 - 80x86
ID String:'Microsoft Corporation'
CheckSum:0x494c
== Default/Initial Boot Entry ==
BootIndicator:0x88 - Bootable
MediaType:0x00 - No Emulation
LoadSegment:0x0000 - 0x7C0
SystemType:0x00
SectorCount:4
LoadRBA:0x00000014(Loc:0x0000a000)
== Direct Mode Boot Image ==
1 Warning(s)
=== Verification Success ===
Watch the "LoadRBA" entry. It says the boot-image is at "Relative Block Address"
0x14 hex (=20 Decimal)
Now enter the following command to extract the boot-image from the ISO:
dd if=E:CORP2IN1.ISO of=E:CORP2IN1_ENBOOTWXP.BIN bs=2k count=1 skip=20
Within seconds, a boot-image BOOTWXP.BIN is generated in E:CORP2IN1_EN which is identical to the BOOT.BIN we previously used. In the above command, "bs' stands for Block Size, "count" stands for Total Number of Block occupied by the boot-image (1 for NT-type boot sector and 720 for Win9X-type floppy image) and skip is the Number of Block to Skip reading before the boot-image.
With these 2 Side Orders, you should be able to have the most updated boot-image coming along with your downloaded ISO. Smile!
New content segment has been put in [12-19-2001] (Part 4), Check it out...
Last edited by khauyeung at Jul 20 2002, 10:09 AM