Modifying ISO to include per-user files

[Todd N]

Hello,
 
After creating a LiveCD ISO image, I'd like to be able to make CDs that are essentially identical, but have a small set of unique per-user files.  I have tried mounting the ISO, copying its contents to a regular directory, making my changes on the Live CD file system (not the internal squashfs file system) and recreating the ISO using mkisofs.  However, this new ISO (when burned to a CD) refuses to boot.
 
Is there a way I can modify the ISO image to include my per-user files on the /mnt/live file system for each user (and have the resulting ISO be bootable), rather than running the whole livecd-creator process each time I want a new CD?
 
Thanks,
Todd

[Pedro Silva]

Hi !

Add your scripts and changes to sections %post and %post --nochroot in
your .ks file.

Regards,

Pedro Silva

Sex, 2008-06-27 às 09:16 -0700, Todd N escreveu:
> Hello,
>
> After creating a LiveCD ISO image, I'd like to be able to make CDs
> that are essentially identical, but have a small set of unique
> per-user files.  I have tried mounting the ISO, copying its contents
> to a regular directory, making my changes on the Live CD file system
> (not the internal squashfs file system) and recreating the ISO using
> mkisofs.  However, this new ISO (when burned to a CD) refuses to boot.
>
> Is there a way I can modify the ISO image to include my per-user files
> on the /mnt/live file system for each user (and have the resulting ISO
> be bootable), rather than running the whole livecd-creator process
> each time I want a new CD?
>
> Thanks,
>
> Todd
>
> --
> Fedora-livecd-list mailing list
> [e-mail]
> https://www.redhat.com/mailman/listinfo/fedora-livecd-list

[Jeremy Katz]

On Fri, 2008-06-27 at 09:16 -0700, Todd N wrote:
> After creating a LiveCD ISO image, I'd like to be able to make CDs
> that are essentially identical, but have a small set of unique
> per-user files.  I have tried mounting the ISO, copying its contents
> to a regular directory, making my changes on the Live CD file system
> (not the internal squashfs file system) and recreating the ISO using
> mkisofs.  However, this new ISO (when burned to a CD) refuses to boot.
> Is there a way I can modify the ISO image to include my per-user files on the 
> /mnt/live file system for each user (and have the resulting ISO be bootable), 
> rather than running the whole livecd-creator process each time I want a new CD?

You'll have to run mkisofs with the appropriate options for making the
CD bootable on your arch.   On x86, that's something like 'mkisofs -b
isolinux/isolinux.bin -c isolinux/isolinux.cat -no-emul-boot
-boot-info-table -boot-load-size 4 ....'

Alternately, you can also use the --base-on support to build derivative
images

Jeremy

[Todd N]

Thanks much for the info, Jeremy.  I ran the mkisofs script as you specified below (we are on an i386 architecture) and re-burned a CD from the newly-created ISO file.  On booting, it gets to the point where it says "Booting the kernel.", hangs for a few seconds, then the following appears on the screen:
 
--------------------------------------
WARNING:  Cannot find root file system!
--------------------------------------
 
Create symlink /dev/root and then exit this shell to continue the boot sequence.
 
bash-3.2#
 
Any thoughts?  Something obvious I am missing?
 
Thanks,
Todd

--- On Mon, 6/30/08, Jeremy Katz  wrote:

From: Jeremy Katz 
Subject: Re: [Fedora-livecd-list] Modifying ISO to include per-user files
To: [e-mail], [e-mail]
Date: Monday, June 30, 2008, 9:51 AM

On Fri, 2008-06-27 at 09:16 -0700, Todd N wrote:
> After creating a LiveCD ISO image, I'd like to be able to make CDs
> that are essentially identical, but have a small set of unique
> per-user files.  I have tried mounting the ISO, copying its contents
> to a regular directory, making my changes on the Live CD file system
> (not the internal squashfs file system) and recreating the ISO using
> mkisofs.  However, this new ISO (when burned to a CD) refuses to boot.
> Is there a way I can modify the ISO image to include my per-user files on

the
> /mnt/live file system for each user (and have the resulting ISO be

bootable),
> rather than running the whole livecd-creator process each time I want a

new CD?

You'll have to run mkisofs with the appropriate options for making the
CD bootable on your arch.   On x86, that's something like 'mkisofs -b
isolinux/isolinux.bin -c isolinux/isolinux.cat -no-emul-boot
-boot-info-table -boot-load-size 4 ....'

Alternately, you can also use the --base-on support to build derivative
images

Jeremy

[Todd N]

Any thoughts on my prior message?
 
Also, an important thing I have noticed is that when I do NOT have persistence installed on a bootable USB drive (or when I have a bootable CD), the path to the boot media is available as /mnt/live.  However, when I include persistence on a bootable USB, there is no path to the boot media, and the path /mnt/live exists but is empty.  As I am counting on pulling several files in from the boot media (but outside the squashfs file system) into my local file system, it is important that there be consistency in where I might find these files, whether or not persistence is installed on the boot media.
 
Can the /mnt/live path be enabled on a bootable USB with persistence installed?
 
Also, another possibility might be to include the external files I need in the actual persistence overlay.  Can I move files into this area?  If so I will not need to do surgery on the squashfs file system.
 
Thanks much for any help that can be offered.
 
Todd

--- On Mon, 6/30/08, Todd N  wrote:

From: Todd N 
Subject: Re: [Fedora-livecd-list] Modifying ISO to include per-user files
To: [e-mail]
Date: Monday, June 30, 2008, 1:55 PM

Thanks much for the info, Jeremy.  I ran the mkisofs script as you specified below (we are on an i386 architecture) and re-burned a CD from the newly-created ISO file.  On booting, it gets to the point where it says "Booting the kernel.", hangs for a few seconds, then the following appears on the screen:
 
--------------------------------------
WARNING:  Cannot find root file system!
--------------------------------------
 
Create symlink /dev/root and then exit this shell to continue the boot sequence.
 
bash-3.2#
 
Any thoughts?  Something obvious I am missing?
 
Thanks,
Todd

--- On Mon, 6/30/08, Jeremy Katz  wrote:

From: Jeremy Katz 
Subject: Re: [Fedora-livecd-list] Modifying ISO to include per-user files
To: [e-mail], [e-mail]
Date: Monday, June 30, 2008, 9:51 AM

On Fri, 2008-06-27 at 09:16 -0700, Todd N wrote:
> After creating a LiveCD ISO image, I'd like to be able to make CDs
> that are essentially identical, but have a small set of unique
> per-user files.  I have tried mounting the ISO, copying its contents
> to a regular directory, making my changes on the Live CD file system
> (not the internal squashfs file system) and recreating the ISO using
> mkisofs.  However, this new ISO (when burned to a CD) refuses to boot.
> Is there a way I can modify the ISO image to include my per-user files on

the
> /mnt/live file system for each user (and have the resulting ISO be

bootable),
> rather than running the whole livecd-creator process each time I want a

new CD?

You'll have to run mkisofs with the appropriate options for making the
CD bootable on your arch.   On x86, that's something like 'mkisofs -b
isolinux/isolinux.bin -c isolinux/isolinux.cat -no-emul-boot
-boot-info-table -boot-load-size 4 ....'

Alternately, you can also use the --base-on support to build derivative
images

Jeremy
--
Fedora-livecd-list mailing list
[e-mail]
https://www.redhat.com/mailman/listinfo/fedora-livecd-list

[Todd N]

Can someone point me in the direction of more extensive documentation on the -base_on option?  So far I haven't found much more than what's on the livecd-tools man page:  "Add packages to an existing live CD iso9660 image."  How do I use this option?  Does this work only for packages, or can I simply replace files as well?  Do I need a kickstart file?  Any pointers are appreciated.
 
Thanks,
Todd

--- On Mon, 6/30/08, Jeremy Katz  wrote:

From: Jeremy Katz 
Subject: Re: [Fedora-livecd-list] Modifying ISO to include per-user files
To: [e-mail], [e-mail]
Date: Monday, June 30, 2008, 9:51 AM

On Fri, 2008-06-27 at 09:16 -0700, Todd N wrote:
> After creating a LiveCD ISO image, I'd like to be able to make CDs
> that are essentially identical, but have a small set of unique
> per-user files.  I have tried mounting the ISO, copying its contents
> to a regular directory, making my changes on the Live CD file system
> (not the internal squashfs file system) and recreating the ISO using
> mkisofs.  However, this new ISO (when burned to a CD) refuses to boot.
> Is there a way I can modify the ISO image to include my per-user files on

the
> /mnt/live file system for each user (and have the resulting ISO be

bootable),
> rather than running the whole livecd-creator process each time I want a

new CD?

You'll have to run mkisofs with the appropriate options for making the
CD bootable on your arch.   On x86, that's something like 'mkisofs -b
isolinux/isolinux.bin -c isolinux/isolinux.cat -no-emul-boot
-boot-info-table -boot-load-size 4 ....'

Alternately, you can also use the --base-on support to build derivative
images

Jeremy