LinuxQuestions.org
Help answer threads with 0 replies.
Home Forums Tutorials Articles Register
Go Back   LinuxQuestions.org > Forums > Linux Forums > Linux - Distributions > Linux From Scratch
User Name
Password
Linux From Scratch This Forum is for the discussion of LFS.
LFS is a project that provides you with the steps necessary to build your own custom Linux system.

Notices


Reply
  Search this Thread
Old 01-29-2002, 10:10 PM   #1
JoeLinux
Member
 
Registered: Dec 2001
Location: Marietta
Distribution: Slackware 8.0
Posts: 95

Rep: Reputation: 15
Question LFS without a host system? (read on..I need more subject space than I have)


I have begun my quest into LFS (kinda. I started downloading the stuff, and I only have an hour left). But, I have been wondering.

How do the distros bootup into a fully working system with minimal capabilities with nothing at all to work off of. For Gentoo (www.gentoo.org) the boot cd puts you into a fully working (seemingly) but limited system, with only a few commands, but the only ones that you need. How do they do that?

I would like an explanation as detailed as you wanna give me. Don't dumb it down.
 
Old 01-29-2002, 10:22 PM   #2
lfslinux
LFS Maintainer
 
Registered: Jan 2002
Location: Canmore, Alberta, Canada
Distribution: Linux From Scratch
Posts: 372

Rep: Reputation: 30
Re: LFS without a host system? (read on..I need more subject space than I have)

Quote:
Originally posted by JoeLinux
I have begun my quest into LFS (kinda. I started downloading the stuff, and I only have an hour left). But, I have been wondering.

How do the distros bootup into a fully working system with minimal capabilities with nothing at all to work off of. For Gentoo (www.gentoo.org) the boot cd puts you into a fully working (seemingly) but limited system, with only a few commands, but the only ones that you need. How do they do that?

I would like an explanation as detailed as you wanna give me. Don't dumb it down.
You may want to post this in the Linux From Scratch forum (under the Distribution forum)?

Secondly, I'm not quite understanding your question I'm afraid. Perhaps you can dumb it down for me a bit
 
Old 01-30-2002, 03:33 AM   #3
Mik
Senior Member
 
Registered: Dec 2001
Location: The Netherlands
Distribution: Ubuntu
Posts: 1,316

Rep: Reputation: 47
I'm not sure if I understand your question fully. But I think you wanted to know how they get an os running without installing anything to your harddrive.
Booting from cdrom is done kinda similar to booting from floppy. There is actually a boot image on the floppy. This image can be 2.8mb and is kinda seen as the same way as the floppy image would be seen. Later on in the booting stage after it recognizes the cdrom filesystem it can read the rest of the files on the cd for whatever actions need to be done next.
The only real problem is that a cdrom is only readable and not writeable. So what gets done is a ramdisk gets created to write files too. If you look at the layout of the basic linux directory structure. The only directories that will need to get written too when running is /var and /tmp.
If you follow that layout you can create a bootable cd which can do almost anything without ever needing a harddisk.
 
Old 01-30-2002, 12:46 PM   #4
JoeLinux
Member
 
Registered: Dec 2001
Location: Marietta
Distribution: Slackware 8.0
Posts: 95

Original Poster
Rep: Reputation: 15
Talking Thanks!

Well, you understood the question perfectly That was just what I wanted to know. So, basically, it would be a boot image on a CD, that then copies files onto a RAMdisk, which can then run like on a hard drive. That seems pretty simple. The technical details are left out though =( Anyone know a good site on how to do this? Or am I oversimplifying this.
 
Old 01-31-2002, 04:30 PM   #5
notsoevil
Member
 
Registered: May 2001
Location: Louisville, Kentucky, USA
Distribution: RedHat ES
Posts: 120

Rep: Reputation: 15
First, this whole thing sounds familiar.

see: http://www.linuxquestions.org/questi...threadid=12234

Second, see:

http://hints.linuxfromscratch.org/hi...ot-cd_easy.txt
http://hints.linuxfromscratch.org/hints/bootcd.txt
http://hints.linuxfromscratch.org/hi...bare_build.txt
http://www.bablokb.de/bblcd/

I am currently (as the first thread above kinda shows) trying to do something similar. I will provide full details when done.
 
  


Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off



Similar Threads
Thread Thread Starter Forum Replies Last Post
make configure-host for binutils-2.16.1 fails under 7.0-cross-lfs-20051019-x86_64 Basel Linux From Scratch 2 10-24-2005 11:07 PM
Host System's LFS installs with shotokan Linux From Scratch 8 04-16-2005 03:34 PM
LFS install trouble -- using debian sarge as host gremesh Linux From Scratch 1 11-23-2004 06:53 PM
LFS install trouble -- using Knoppix 3.6 as host hell_carnage Linux From Scratch 3 11-18-2004 07:09 AM
Change from Read only to Read Write File System? justiceisblind Linux - Newbie 3 03-03-2002 07:23 PM

LinuxQuestions.org > Forums > Linux Forums > Linux - Distributions > Linux From Scratch

All times are GMT -5. The time now is 03:22 AM.

Main Menu
Advertisement
My LQ
Write for LQ
LinuxQuestions.org is looking for people interested in writing Editorials, Articles, Reviews, and more. If you'd like to contribute content, let us know.
Main Menu
Syndicate
RSS1  Latest Threads
RSS1  LQ News
Twitter: @linuxquestions
Open Source Consulting | Domain Registration