three stage GRUB boot ... how?

Forum: USB booting
Topic: three stage GRUB boot ... how?
started by: hrwusesdsl

Posted by hrwusesdsl on Feb. 26 2006,03:05

i was very pleased with the "usb boot floppy" image. maybe too pleased.
i downloaded the floppy image; rawrote it to floppy; plugged in new usb pendrive loaded with NON-bootable DSL files; booted from floppy and PRESTO -- FIRST TIME -- DSL came up. Nice. now i want more. much more.
{{ USB drive is KINSTON "DATA TRAVELER" 256 MB }}

my poor old computer can not boot directly from usb. it can boot directly from cd. and of course from floppy as mentioned.

floppy too slow. cd too inconvenient. "inconvenient" because you folks too productive -- new dal extensions; new base version all the time. nuisance burning new cd every week. even more vexing: want to try different boot options - maybe scsi from friend; maybe this; maybe that; want to change boot config options every other day. want to stop burning cds.

my solution: make bootable cd but not DSL. CD boots using floppy emulation from Freedos floppy. CD has DOS script -- autoexec -- which executes GRUB FOR DOS. GRUB FOR DOS has memdrive feature which theoretically can load and start your usb-boot-bloppy image {{straight off the cd you see. faster than simple floppy boot. is this confusing??}} HOWEVER i want my GRUB boot options config file on back on a floppy so it can be changed easily. GRUB can do this. SYSLINUX cannot. GRUB command for "remote" boot options file on floppy is...
grub.exe --config-file=(fd0)/grubcfg.ini

PROBLEM In the config file on the floppy you are supposed to write commands like
root (cd)
kernel (cd)/dsl/lunux24
blablabla.....................
GRUB then sez it cannot lfind file linux24! Even tho it just booted from the 7^&(((** CD! What to do??

{{ i REFUSE to use your boot floppy as manufactured. too slow. worse, i want to load ONE floppy with ALL NECESSITIES -- LIKE ALL SAVED Opera bookmarks. My weird CD has pause in script to prompt insertion of floppy for GRUB config file during boot... that works, ie GRUB finds config file & displays my GRUB boot options -- like boot DSL in USB; boot RIP Linux on CD; GEEXBOX on CD; etc but none of the options work ]]

Posted by cbagger01 on Feb. 27 2006,05:10

Does GRUB support your CDROM drive?

Also, is the file located at

/dsl/linux24 (I assume that lunux24 was just a typo)

or is it at

/boot/isolinux/linux24

or somwhere else?

Posted by hrwusesdsl on Feb. 27 2006,12:51

Thanx, cbagger, for some attention to my weird project.
Dunno if GRUB "supports" my cd. With fewer typos, here is what I did:

I made a Bootable floppy using Freedos. The floppy has GRUB FOR DOS. The AUTOEXEC issues a message that sez "Insert configuration floppy now" and it pauses. After the pause it calls the DOS GRUB with this option: --config-file=(fd0)/grubcfg.ini

Using Easy CD Creator under Windows 98 I burned a "floppy emulation" bootable CD. The BOOTCATs came from the bootable Freedos floppy. The other things on the CD are---
/DSLFLOPS/
/GEEXBOX/
/INSERT/
/RIP/
The CD booted fine and found my grub cfg file on floppy. I changed the floppy cfg file so often I cannot repeat every command I tried. To boot DSL I intended to use
kernel /DSLFLOPS/BOOTUSB/linux24
because that is where I put the DSL usb-boot-floppy kernel, but i never got that far. GRUB said things like "Unable to mount partition"

I also experimented with Linux grub in DSL. Using the usb boot floppy the way it was intended, I booted the DSL system in my Kingston Traveler 256 MB pendrive. I opened a shell ; changed to ~/boot/grub and erased the device.map file; then created a new device map file with
GRUB --device-map=grub.dev then looked at the file. It read:
(fd0) /dev/fd0
(hd0) /dev/hda
(hd1) /dev/sda
I edited this device file and changed sda to hdc but got similar resutls. My CD drive is new model in last two years. 52x read only ASUS. Any comments form anyone appreciated. Thanx.

Posted by cbagger01 on Feb. 27 2006,18:10

Hmm. If your CD is a standard ATAPI internal CDROM drive for a desktop computer, I would hope that GRUB could support it.

Otherwise, you may be able to install the CDROM extensions to the FreeDOS disk and then use loadlin to load the files from D:\ drive (or whatever drive letter is assigned to your CDROM).

I am not very familiar with grub, so I am not much help there.

You might want to do the following:

1) Make sure that the filepath uppercase/lowercase letter spelling is correct if Grub is case sensitive.

2) Make sure that Grub understands that the linux24 kernel image is a COMPRESSED image, like is usually called by name vmlinuz

Good Luck.

Posted by hrwusesdsl on Mar. 01 2006,00:34

Thank you much. will study LOADLIN

Posted by cbagger01 on Mar. 01 2006,06:57

Make sure that you get the version that supports booting of a linux 2.4.x version kernel.

I think it is 1.6c if my memory is correct. It's listed in the readme/notes for loadlin