ISO to USB using Hybrid ISOs

[smcs_steve]

Update (slightly off topic for this thread)>
I gave MultiBootISO (GRUB2) a try using the following stanza -- PCLOS iso was unmodified, just renamed as test.iso for convenience.

title test.iso
find --set-root /test.iso
map --heads=0 --sectors-per-track=0 /test.iso (hd32)
map --hook
chainloader (hd32)

Nearly, but no blue ribbon yet.  The iso boots to startup menu, proceeds to the stage> detecting hardware, then some services start OK but many libs fail to load and the process stalls at keyboard selection screen. (no keybd/mouse)
This might be where Just19 says "I told you so!"  
Any help?
>Steve

[Was_Just19]

Hey _steve,
                     maybe you don't want to reinvent lusbc .....  but it has occurred to me 
Really I had hopes for this - to be incorporated into lusbc, to enable the addition of 'foreign' ISOs to a usb device. On that I have not given up hope - yet.

There are things that need to be determined, such as

any possibility of being able to use Persistence when using grub to boot the device, without the need to break open the ISO and edit the boot config file, before running isohybrid..
I have not tried to see if I can arrange persistence on a logical partition. I would hope so, because if not then one such installation would need two primary partitions.

It seems it may not be possible to have any other OS on a lower numbered partition of the device .......  unless some of the, as yet unused, options help in that regard.

It does appear that this is limited to primary partition installs.

**
The more I try playing with this, the more annoyed I get at not having any real information about the options. For something released in 2008 there sure is a dearth of info or even real life experience reports.

@ _steve ......  care to throw out some of your thoughts on the persistence angle for others to think about?

Just for clarity ....  I have Puppy Hybrid and a couple of PCLOS (lusbc) installs on a USB stick working fine ....  using the first partition for Puppy.
 
regards.

[smcs_steve]

Hey _steve,
any possibility of being able to use Persistence when using grub to boot the device, without the need to break open the ISO and edit the boot config file, before running isohybrid..

The ISO 9660 filesystem is encapsulated in a partition (which starts at offset zero, which may confuse some systems.) This makes it possible for the operating system, once booted, to use the remainder of the device for persistent storage by creating a second partition.

http://syslinux.zytor.com/wiki/index.php/Doc/isolinux

Hmmmmm...

[Was_Just19]

Hey _steve,
any possibility of being able to use Persistence when using grub to boot the device, without the need to break open the ISO and edit the boot config file, before running isohybrid..

The ISO 9660 filesystem is encapsulated in a partition (which starts at offset zero, which may confuse some systems.) This makes it possible for the operating system, once booted, to use the remainder of the device for persistent storage by creating a second partition.

http://syslinux.zytor.com/wiki/index.php/Doc/isolinux

Hmmmmm...

Yeah, saw that some time ago .......  but like everything else concerning this isohybrid, there seems to be no explanations about the hows and whys .....    .....  unless you have found something?

[smcs_steve]

The other method - as inferred earlier
(This is now my preferred method!)
Project> make USB stick bootable with persistence >my.iso (695 MB)
Prepare 4GB USB stick>  Create partition table, Create 1GB + 3GB partitions as ext2 format,
label 3GB partition as MyData_
In terminal as root --> cd /to/where/my.iso/is
blkid
note down /dev/sdx for USB stick and UUID for MyData_ partition
open my.iso with ISO Master, extract /isolinux/isolinux.cfg and edit label and UUID as required> eg:

default 0
prompt  1
timeout 90
ui gfxboot.com bootlogo

label pclinuxos-kde-2010.12 with persistence
    kernel vmlinuz
    append livecd=livecd initrd=initrd.gz fromusb root=/dev/rd/3 changes_dev=UUID=90e983f9-38f5-4db9-b7db-1fe1655b7a48 apci=on vga=788 keyb=us vmalloc=256M splash=silent
label pclinuxos-kde-2010.12 Safe boot
    kernel vmlinuz
    append livecd=livecd initrd=initrd.gz root=/dev/rd/3 acpi=off vga=normal keyb=us vmalloc=256M noapic nolapic nopinit vesa

Replace edited file to /isolinux/isolinux.cfg  and save iso as> eg: myH.iso   Close ISO Master.

Back in terminal>
isohybrid -partok myH.iso
dd if=myH.iso of=/dev/sdx1

Check sdx1 boot flag is set.   task finished! (no GRUB install required)

I've noticed that this approach appears to give a better compatibility range of PCs and avoids the instabilities with persistence mentioned here> http://www.pclinuxos.com/forum/index.php/topic,85609.msg710057.html#msg710057  
I'll need to do more testing to confirm this -- and discover why. (unstable on laptops running low RAM only?)

>Steve
Edit2> changes to boot stanza.
Note.:   UUID  for MyData_ partition can be modified afterwards (ext2) -- in Terminal as root>
[root@localhost ~]# tune2fs -U 90e983f9-38f5-4db9-b7db-1fe1655b7a48 /dev/sdb2
details here>  http://atlanticlinux.ie/blog/?p=101

[Was_Just19]

So you haven't found any new info regarding the hybrid options?

Neither have I.

Yes I have used that method to get persistence .....  but it does involve breaking open each ISO to edit the boot config file ......  not very helpful when testing a variety of ISOs unfortunately.

You remarked in an earlier post about getting persistence without this being necessary ......  what is the present situation?