Re: Reusing the cdrom drive

On Wed, 2003-09-24 at 10:09, Seth David Schoen wrote:
> Alastair Munro writes:
> 
> > Hello,
> > 
> > I have backups on cdr, and want to restore them under LNX-BBC. However, after
> > booting LNX-BBC the cdrom cannot be unmounted, as it says its busy. I can't see which
> > process has the cdrom open (did an lsof). I even tried to kill a couple of the
> > processes, to see if that makes a difference. Most of the utilities I want are
> > in the ram drive (I think), so I don't think I need to run stuff off the LNX-BBC
> > cdrom when accessing my cd.
> > 
> > Anyone any ideas how I can unmount the LNX-BBC cdrom, and swap if for one of my
> > backup cds? If if its a case that I can't use LNX-BBC after swapping the cds,
> > then I can always reboot LNX-BBC again. I'm just using LNX-BBC for hard disk
> > recovery.
> > 
> > Many thanks in advance.
> 
> Currently LNX-BBC can't do what you want at all, because it has a
> filesystem mounted from the CD.  All the LNX-BBC software is contained
> in that filesystem.  (The kernel, through the cloop driver, has the
> CD-ROM open -- not a user process.)  None of the LNX-BBC software is
> initially in the RAM disk.
> 
> I just read that the new Knoppix supposedly has a way of loading
> itself into memory, so that the CD can be ejected.  (I guess you have
> to have a lot of memory, since Knoppix uses a full CD.)  We've been
> talking about implementing that; among other things, it might make it
> practical to netboot LNX-BBC.
> 
> If you have a floppy drive, you might want to try using tomsrtbt.  (If
> not, you can boot tomsrtbt from a CD as an El Torito emulation mode
> image, and then you will probably be able to remove the CD and
> continue using tomsrtbt.)

I made a set of scripts for munging a lnxbbc image to do a few extra
things.  One of the features adds a boot option that reads the 
compressed image off the CD into a 50MB ramdisk, unmounts the CDROM,
and runs from ramdisk, leaving the CDROM free for restores and such. 
I use v2.1 of the lnx-bbx modified by these scripts to do just what 
Alastair is wanting to do.  

There are also some other scripts for inserting a new kernel into the 
disc image or using isolinux as the cdrom boot method, but you might 
not care about those.

   http://www.mock.com/bbcmods/

Let me know if you have any problems.

jeff