Creating a Live CD....some queries

s26c.sayan · 2007-07-14 11:32:25

Hello!
I'm trying to create a Live CD from my current Arch installation. I'm not using any of the 'automated' scripts (like Larch, makeliveiso or even those from linux-live.com), but trying to do it the 'hard way', i.e. right from scratch! I'v got a query regarding the linuxrc script in the initial ramdisk image.

How can I add auto-detection of CD drive to the linuxrc script? Currently, I've simply added 'mount -t iso9660 /dev/hdc /cdrom' since I know my cd drive is located at /dev/hdc, and it works ok. However, for different system, I must have a CDROM detection ability!
Any help and suggestion will be greatly appreciated.

gradgrind · 2007-07-15 06:06:50

Basically you need to go through all the possible devices (there are various ways of getting these, looking in /dev or /proc), mount them, see whether they are your live CD, unmount if not, go to next step if so.

You can see how I did it in larch by getting the initcpio_larch package from ftp://archie.dotsrc.org/projects/archie/larch/dev3A and looking at the 'larch1' hook (in /lib/initcpio/hooks).

Good luck!

s26c.sayan · 2007-07-15 20:46:43

Well I've added a line to linuxrc script to mount a sysfs and use it to locate the cdrom.

But, currently I'm facing some problems with unionfs. It seems that the root fs is being tried to be remounted as read only, and then I'm getting kernel panics.
Is there any way in arch linux where I can stop the system to try and remount root fs as ro at boot time?

and Gradgrind, is there any way I can use your larch scripts to generate a live cd from a already installed arch linux system (like in the linux-live scripts)?

gradgrind · 2007-07-16 04:05:11

s26c.sayan wrote:

Is there any way in arch linux where I can stop the system to try and remount root fs as ro at boot time?

You'll need to modify /etc/rc.sysinit to work as a live CD, that's where all the initial mounts are done.

s26c.sayan wrote:

and Gradgrind, is there any way I can use your larch scripts to generate a live cd from a already installed arch linux system (like in the linux-live scripts)?

In principle, yes. Your installed system needs the following packages: squashfs-tools, initcpio_larch, cdrkit, dvd+rw-tools. You will also need a 'profile' (see the docs), but the 'addedpacks' and 'locale.gen' part is not needed. I can't remember at the moment how to change the name of the directory containing the installation ('ArchImage'), but you can change the build path in 'config_larch'. You could always use a symlink from 'ArchImage' to your root partition. Then you can build an iso using the -b option to mklarch. Of course you can't do this while you are running the system to be made 'live' - you need to use a system on another partition, or a live CD (warning for live CD - lots of space needed, use a large swap partition, or build on a different hd partition).

As you can see, larch wasn't really designed for this, it wasn't important to me, and I think linux-live does a pretty good job of this sort of thing. I believe archie can also do this, and a new release of that should be available soon.

I'm afraid I'm away for a while now, so if you need anything else from me, it will have to wait a few weeks.

Good luck!

s26c.sayan · 2007-07-16 11:23:38

Thank you for your replies,

gradgrind wrote:

s26c.sayan wrote:
Is there any way in arch linux where I can stop the system to try and remount root fs as ro at boot time?
You'll need to modify /etc/rc.sysinit to work as a live CD, that's where all the initial mounts are done.

Can anyone tell me how exactly do I do that? [:P]

gradgrind · 2007-08-08 05:13:40

s26c.sayan wrote:

Thank you for your replies,
gradgrind wrote:
s26c.sayan wrote:
Is there any way in arch linux where I can stop the system to try and remount root fs as ro at boot time?
You'll need to modify /etc/rc.sysinit to work as a live CD, that's where all the initial mounts are done.
Can anyone tell me how exactly do I do that? [:P]

Hi, did you get any further, or do you still need some help?

s26c.sayan · 2007-08-08 07:20:09

Hello Gradgrind, nice to see you back!

Actually, the problem I was having seems to be because of unionfs. I tried using aufs instead, but just couldn't compile it into my kernel! (Didn't try hard enough, I guess!)
The makeliveiso scripts from Archie didn't work either, so finally I resorted to Linux_live Scripts. They worked, and the live CD is finally ready! Also, as these scripts use lzma compression with squashfs, the size of iso was lesser!

So, automation finally won over trying to do things right from scratch!

Thanks for your help! Now I'm trying to make the live CD into a live-CUM-install CD......maybe I'd need some help from you on that!

Arch Linux

#1 2007-07-14 11:32:25

Creating a Live CD....some queries

#2 2007-07-15 06:06:50

Re: Creating a Live CD....some queries

#3 2007-07-15 20:46:43

Re: Creating a Live CD....some queries

#4 2007-07-16 04:05:11

Re: Creating a Live CD....some queries

#5 2007-07-16 11:23:38

Re: Creating a Live CD....some queries

#6 2007-08-08 05:13:40

Re: Creating a Live CD....some queries

#7 2007-08-08 07:20:09

Re: Creating a Live CD....some queries

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