Multiboot CD-ROM via Grub4DOS External links Options

[ilko]

In the latest posts in pmagic forum, Patrick has accepted the idea to include only customized grub4dos.lst in root of his builds.
Since pmagic.iso is going to be loaded by grub4dos anyway, there is no point to load a second grldr in pmagic.iso. It just has to use the config file in root of pmagic.iso.

CODE

title Start PMagic
find --set-root /pmagic-svn.iso
map /pmagic-svn.iso (hd32)
map --hook
root (hd32)
configfile (hd32)/grub4dos.lst

This will be an easy way to request similar functionality from other live CD maintainers. They will not have to change Isolinux or whatever they use, to grub4dos. And anoyne creating multiboot will have to change only the name of the ISO file in his menu.lst.
Seeing grub4dos.lst in root of an ISO will mean that the ISO is grub4dos aware.

You probably already saw the last posts, what do you think?

I am on my way to UBCD, in latest v5 beta, pmagic is included. Now we have to figure out how to start pmagic from UBCD.ISO.
PMagic is already in directory \pmagic. That's good. Simple solution is to rename UBCD.ISO to PMAGIC.ISO or whatever name it was extracted from. Will have to request additional file or a commented out line in grub4dos.lst to indicate what ISO name PMagic was extracted from, as well as to include the latest version, which should be released soon.

CODE

title Start UBCD
find --set-root /pmagic-svn.iso
map /pmagic-svn.iso (hd32)
map --hook
root (hd32)
configfile (hd32)/grub4dos.lst

@SamK- sorry, I forgot to answer, haven't done anything with clonezilla.

[was_jaclaz]

You probably already saw the last posts, what do you think?

But anyway Patrick and ilko appear to be making the greatest progresses, so this will most probably be unneeded.

But still, I like exploring alternatives.

Remember that Patrick has been EXCEPTIONALLY present and positive in his attitude towards our requests and comments, Authors of other distro's or minidistro's may not be as much available to this kind of requests/suggestions, and TIMTOWTDI:
http://en.wikipedia.org/wiki/There's_m...ne_way_to_do_it
or, if you prefer,

There's more than one way to skin a cat

http://www.worldwidewords.org/qa/qa-mor1.htm

jaclaz

[SamK]

The pmagic-svn.iso needs to be contiguous.

Use CONTIG:
http://technet.microsoft.com/en-us/sysinte...s/bb897428.aspx

to check.

Is this a suggestion to overcome the Autodetect... and Disk read error messages? Contig was not used to establish the following results. I would prefer to build each ISO using mkisofs to obviate this possible problem but need some additional information (detailed below).

Can you also try with the (hd33) method?

RESULTS

map /images/pmagic-svn.iso (hd32)
map --hook
map (hd32)/PM.ISO (hd33)

Disk read error.

map /images/pmagic-svn.iso (hd32)
map (hd32)/PM.ISO (hd33)

Selected disk does not exist

can you give some details about the following:
1) the pmagic-svn.iso is the one here:
http://partedmagic.com/beef_drapes/pmagic-...7Jun,221033.zip
or is it another one? Please give a link to it.
(that one appears to be a truncated archive)

Patrick normally updates his svn versions overnight (UK time). In this process each ISO is given a filename that includes a date element which changes depending upon the date of upload. The link you are trying has probably been superseded with a newer version. Try http://partedmagic.com/beef_drapes and download the most recent ISO. There are usually three files shown for booting from CD-ROM, USB or PXE.

Which apps did you use for these steps?:

Created ISO containing BZIMAGE and INITRD (named PM.ISO)
Injected PM.ISO in \ of pmagic-svn.iso

A commercial product called WinISO. This is able to extract from ISO, create ISO and inject into ISO. This may also account for the previously mentioned disk errors - hence my preference for mkisofs. Can we agree on a common set of software tools to avoid as many 'incompatibilities' as possible?

which options did you use with mkisofs in this step?:

CODE

mkisofs -R -b grldr -no-emul-boot -boot-load-seg 0x1000 -volid "XXX" -o bootable.iso iso_root

Do you happen to know which parameters are used with mkisofs when creating the original pmagic-svn.iso?

No - hence my use of WinISO instead of mkisofs. I will ask Patrick Verner to post it in the Parted Magic forum.

[tinybit]

CODE

map /images/pmagic-svn.iso (hd32)
map --hook
map (hd32)/PM.ISO (hd33)

Disk read error.

Perhaps you are using an older version of grub4dos. Try the latest builds here: http://download.gna.org/grub4dos/
You'd better try the build 2008-06-28 first. If you still got "Disk read error", this would indicate a new bug in grub4dos.

CODE

map /images/pmagic-svn.iso (hd32)
map (hd32)/PM.ISO (hd33)

Selected disk does not exist

map --hook is required before map (hd32)/PM.ISO (hd33) or before any other command that will access files on (hd32).

CODE

map --mem /images/pmagic-svn.iso (hd32)
map --hook
map (hd32)/PM.ISO (rd)
kernel (rd)/BZIMAGE root=/dev/ram0 initrd=/linuxrc keymap=uk livecd vga=normal sleep=0 ramdisk_size=25000 noapic
initrd (rd)/INITRD
boot

Before boot, you may try to free the memory that was used for the mapping:

CODE

map --mem /images/pmagic-svn.iso (hd32)
map --hook
map (hd32)/PM.ISO (rd)
kernel (rd)/BZIMAGE root=/dev/ram0 initrd=/linuxrc keymap=uk livecd vga=normal sleep=0 ramdisk_size=25000 noapic
initrd (rd)/INITRD
map (hd32) (hd32)
map --rehook
boot

Notice the mapping map (hd32) (hd32). Generally mapping a drive to itself really means to delete the map. Then after map --rehook, the memory that was occupied by the virtual CD-ROM will be freed.

Also note that the use of (rd) is not required in this situation. You may just do it as folows:

CODE

map --mem /images/pmagic-svn.iso (hd32)
map --hook
kernel (hd32)/BZIMAGE root=/dev/ram0 initrd=/linuxrc keymap=uk livecd vga=normal sleep=0 ramdisk_size=25000 noapic
initrd (hd32)/INITRD
map (hd32) (hd32)
map --rehook
boot

[tinybit]

Use CONTIG:
http://technet.microsoft.com/en-us/sysinte...s/bb897428.aspx

Someone in a Chinese forum told me that there is a new tool called WinContig(which is better than the Microsoft contig):

http://wincontig.mdtzone.it/en/

[SamK]

@jaclaz

I will ask Patrick Verner to post it in the Parted Magic forum.

mkisofs -R -l -D -b pmagic/isolinux.bin -o pmagic-svn.iso -c pmagic/boot.cat \
-no-emul-boot -boot-load-size 4 -boot-info-table -V "Parted Magic" current

All of the boot process is done in /etc/init.d/rcS

Nobody boots a LiveCD like I do, so I don't know how reliable my ideas might be for other distros.

[SamK]

You probably already saw the last posts, what do you think?

My previously expressed principles:

• simplicity of use
• ease of implementation
• ease of maintenance/change
• repeatable in nature

All well met.

[SamK]

@jaclaz

To ensure everything is contiguous I have repeated the experiment conducted yesterday
see here: http://www.boot-land.net/forums/?showtopic=4902&st=64
with the following amendments:
ISO building conducted using mkisofs
Changed menu.lst (details below)
Parted Magic - pmagic-svn.iso-28Jun,221857.zip
Downloaded from - http://partedmagic.com/beef_drapes/
Unchanged:
Grub4DOS - grub4dos-0.4.3-2008-05-14.zip
Downloaded from - http://grub4dos.jot.com/WikiHome


Stage1 - Create File Structure
ISOBUILD\mkisofs.exe
ISOBUILD\iso_root\gldr and menu.lst
ISOBUILD\iso_root\images\
ISOBUILD\pm\inner\mkisofs.exe
ISOBUILDpm\inner\iso_root\
ISOBUILD\pm\outer\mkisofs.exe
ISOBUILD\pm\outer\iso_root\ All Parted Magic extracted from downloaded ISO (excluding [BOOT])


Stage2 - Create Inner ISO
copy ISOBUILD\pm\outer\iso_root\ pmagic\bzImage to ISOBUILDpm\inner\iso_root\BZIMAGE
copy ISOBUILD\pm\outer\iso_root\ pmagic\initrd to ISOBUILDpm\inner\iso_root\INITRD
ISOBUILD\pm\inner\mkisofs.exe -volid "INNER ISO" -output PM.ISO iso_root


Stage3 - Create Outer ISO
copy ISOBUILD\pm\inner\PM.ISO to ISOBUILD\pm\outer\iso_root\PM.ISO
ISOBUILD\pm\outer\mkisofs.exe -R -l -D -b pmagic/isolinux.bin -c pmagic/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -volid "Parted Magic" -output pmagic-svn.iso iso_boot


Stage 4 - Create the Physical CD-ROM
copy ISOBUILD\pm\outer\pmagic-svn.iso to ISOBUILD\iso_root\images\pmagic-svn.iso
ISOBUILD\mkisofs.exe -R -b grldr -no-emul-boot -boot-load-seg 0x1000 -volid "XXX" -output bootable.iso iso_root
Burn ISOBUILD\bootable.iso to CD-ROM using ImgBurn


At this point we have a contiguous physical CD-ROM containing a contiguous outer.iso containing a contiguous inner.iso


Stage 5 - Booting
menu.lst

CODE

map /images/pmagic-svn.iso (hd32)
map --hook
map (hd32)/PM.ISO (hd33)
map --rehook
kernel (hd33)/BZIMAGE root=/dev/ram0 initrd=/linuxrc keymap=uk livecd vga=normal sleep=0 ramdisk_size=25000 noapic
initrd (hd33)/INITRD
boot

RESULT
Boot/load completes successfully.

Notes:

1. The mkisofs options used in stage 3 are those supplied by Patrick Verner
2. Ensuring everything is contiguous eliminates the previous "disk read" error
3. The --mem option is no longer required
4. (rd) is no longer required

[was_jaclaz]

Is this a suggestion to overcome the Autodetect... and Disk read error messages? Contig was not used to establish the following results. I would prefer to build each ISO using mkisofs to obviate this possible problem but need some additional information (detailed below).

Yes, that kind of error happened to me in the past when using direct mapping (as opposed to --mem mapping) if the file was not contiguous on the media where it was saved.
With --mem option the file is copied to memory and thus automatically made contiguous on-the-fly.

Someone in a Chinese forum told me that there is a new tool called WinContig(which is better than the Microsoft contig):

http://wincontig.mdtzone.it/en/

Thanks for this, very nice little app, cannot say whether it is better or not, but it's nice anyway.

jaclaz

[tinybit]

CODE

map /images/pmagic-svn.iso (hd32)
map --hook
map (hd32)/PM.ISO (hd33)
map --rehook
kernel (hd33)/BZIMAGE root=/dev/ram0 initrd=/linuxrc keymap=uk livecd vga=normal sleep=0 ramdisk_size=25000 noapic
initrd (hd33)/INITRD
boot

Although the virtual CDs (hd32) and (hd33) are not in memory, they can still be freed:

CODE

map /images/pmagic-svn.iso (hd32)
map --hook
map (hd32)/PM.ISO (hd33)
map --rehook
kernel (hd33)/BZIMAGE root=/dev/ram0 initrd=/linuxrc keymap=uk livecd vga=normal sleep=0 ramdisk_size=25000 noapic
initrd (hd33)/INITRD

map  (hd32)  (hd32)
map  (hd33)  (hd33)
map --rehook

boot

When Linux kernel gains control, the mappings will no longer be useful, so we could unload(say, delete) all the mappings. The mapping(say, the emulation) uses conventional memory(about 10KB) for the code, hooking BIOS int 13h.