View Full Version : fromhd works only with vfat

08-22-2005, 08:01 PM
Hi all,
I have GRUB installed on my PC and use it to boot Knoppix 3.9 with the fromhd cheatcode (without having the CD in the drive).
Now I noticed somthing strange: All works fine if the compressed KNOPPIX file is on a partition formatted with the vfat filesystem but if it is on an ext2 partition I get a "kernel panic"...
The reason why I'm writing that is because the new DVD (which I have not yet downloaded) will not fit on vfat because of the file size limitation and I would like to be able to boot without having the DVD in the drive. (Sorry my bad english.)

Please, could someone give me an advice?

Harry Kuhman
08-22-2005, 08:37 PM
will not fit on vfat because of the file size limitation and I would like...
I'm not clear on just what size limitation you have an issue with . As I understand it, Vfat is the extension to FAT file names that lets file names exceed the old 8.3 limit. I currently have the DVD iso, with it's full KNOPPIX_V4.0DVD-2005-08-16-EN.iso name, sitting on my FAT partition (I don't boot from FAT, I burned working DVDs from this ISO). So what doesn't fit?

08-22-2005, 09:37 PM
Thanks for the fast replay.
I read somewhere that there is a file size limitation on fat (one single file can't be bigger then ~ 2 GB).
If I understood correctly, I won't have that problem with vfat, because it is the extension of the fat filesystem.
Very good! Thanks a lot.

Harry Kuhman
08-22-2005, 10:07 PM
The size limitation on Fat32 is 4 gig (minus a byte or two), not 2 gig. The file size limit on ISO9660 is 2 gigs per file and sometimes people get these confused. Older FAT systems did have limits less than 4 gig, but 4 gig is the number for Fat32. Vfat is the name size extension, but has nothing to do with the file size limit (Vfat can give you longer names even on older fat partitions with small file size limits).

Microsoft has other issues (poor Microsoft). Even though you can have a 4 gig file on a FAT32 partition, Microsoft networking will not let you move the file across the network to another computer. You can work around this other ways, either use a 3rd party FTP program and transfer the file that way or, as I did, slice the file up into several hunks that you can transfer and then combine them on the second system.

08-22-2005, 11:14 PM
Good explanation!
I think I won't have any problem because the iso is <4 gig. Will now try to save the huge knoppix file on my vfat partiton.

But I'm still curious why the following works with vfat on /dev/hda1 and not with ext2 on /dev/hda1!

title Knoppix V3.9 Kernel 2.6.11 fromhd
kernel (hd0,4)/boot/bootknoppix3.9/linux ramdisk_size=100000 init=/etc/init apm=power-off vga=791 initrd=minirt.gz nomce BOOT_IMAGE=knoppix fromhd=/dev/hda1 knoppix_dir=knoppix3.9
initrd (hd0,4)/boot/bootknoppix3.9/minirt.gz