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als
03-08-2005, 06:31 PM
Hi all,

When booting knoppix from CD, I see a line that says:


Creating directories and symlinks on /ramdisk...Done

But I can't find that step in the init scripts anywhere.

I want to build a box that will boot from the hard drive, but basically treat the hard drive like a read-only filesystem (just like the CD). It should mount /dev/hd? as ro, so the system coudl be used (and abused) and then be recovered with a reboot.

Can anybody give me a hint on how the root filesystem and all the symlinks on the ramdisk are created when bootinf from CD, so I can mimick it with a hard drive install?

Thanks!

Al

UnderScore
03-08-2005, 07:36 PM
Knoppix loads the kernel and mini root partition from /KNOPPIX-CD-ROOT/boot/isolinux. If you use the 2.4 kernel on knoppix then the kernel loaded is linux24 and the mini root is minirt24.gz. If you use the 2.6 kernel on knoppix then the kernel loaded is linux26 and the mini root is minirt26.gz. You can view the mini root by copying it to another location, unziping it, and loop mounting it.
cd $HOME
cp /KNOPPIX-CD-ROOT/boot/isolinux/minirt24.gz ./
mkdir foobar
gunzip minirt24.gz
sudo mount -t ext2 -o loop minirt24 ./foobar
Inside the minirt you will find a executable script named linuxrc. This linuxrc script is init script for Knoppix.
#!/static/sh
#
# KNOPPIX General Startup Script
# (C) Klaus Knopper (knoppix@knopper.net)
#
#
# This script needs some of the builtin ash commands (if, test, ...)
# mount/umount, insmod/rmmod are also a builtin in ash-knoppix
#
Line at about line 612 to 618 is where the symlinks get created.
I hope this helps.
James

knopx4me
03-10-2005, 05:26 PM
UnderScore

I think this will help me solve my issue also. I am trying to start vdr from withen my CD. vdr requires a folder called /video. I copied this folder to my remaster sources folder. After compression it became /KNOPPIX/video so vdr was not able to see it. So, I want to create a symilink /video to /KNOPPIX/video at start up. I have done several things using the above as follows but all failed:
1- I added a line in linuxrc with code: ln -s /KNOPPIX/video /video
2- I added a line in linuxrc with code: ln -s /KNOPPIX/video /
3- I created a folder /video in ./foobar and made the above similink, but the system ignored that folder.
4- I created a similink at ./foobar to /KNOPPIX/video and same thing it was ignored.
I tried many other thing.
Can you sugesst any thing else?