
Optional package bootCD v.0.2 for fli4l 2.0.3a

  Introduction

   This optional package for the [1]fli4l project provides some scripts
   and modified files to create a bootable CD rather than a boot floppy
   for setting up e.g. an ISDN router.
   Beside the fact, that a CD has a much higher capacity than a floppy,
   the boot process is usually also much faster when booting from a
   recent CD drive, e.g. down to 10-30 seconds even with a large
   configuration instead of somtimes several minutes with floppy disk
   even though configuration was minimalistic.
   The package comes with a modified root filesystems which incorporates
   the neccessary modules in oder to access a CD just after boot
   (ide-cd.o, cdrom.o for cdrom access and isofs.o for access to the
   filesystem used on CDs). As of now, only booting from ATAPI (i.e.
   CDrom drives connected to the IDE bus) is supported, as access to SCSI
   drives would mean to include lots of modules for all the different
   types of SCSI adapters around (thus blowing up things quite a lot)
   whereas some tiny modules do suffice to achieve this for ATAPI drives.
   Moreover ATAPI drives are quite cheap in comparison to SCSI drives and
   the basic intension of fli4l is to be run on low-cost, somewhat
   outdated hardware anyway. So if you own a SCSI drive only but would
   like to boot from CD, better consider getting an old ATAPI drive
   instead of adding SCSI modules to this package.

  Modified files

   The files in this package follow the directory standard as defined by
   the fli4l project, however some files will be modified as follows:

   img/rootfs.gz: 
     root filesystem with CD boot related modules and modified startup 
     script (/etc/rc)

   img/syslinuxcd.cfg: 
     sylinux configuration with specification of CD rom drive

   opt/etc/rc.local:
     modified in respect to appropriate generation of fstab

   mkclean.{sh|.bat}:
     will clean up also files related to boot CD creation

   If you intend to use this package together with the hd package (for
   installation onto a harddisk), make sure that you also unpack the file
   hd_update.zip located in the root directory of the fli4l tree after
   you unpacked the hd package. This will additionaly modify the
   following files of the hd package:

   config/hd.txt new setting HDINSTALL_MOUNT_BOOT hat determines whether
   the boot partition should be mounted after harddisk installation. (for
   harddisk installation, the parameter MOUNT_BOOT of the base fli4l
   package must be set set to 'ro' or 'rw', but not to 'no', because the
   files could not be copied to the harddisk otherwise. however, setting
   HDINSTALL_MOUNT_BOOT='no' will allow to install fli4l on a harddisk,
   but have the boot partition not mounted afterwards when finally
   booting from harddisk)
   config/hd.txt comprises check for HDINSTALL_MOUNT_BOOT
   opt/hd.txt CD rom related modules skipped, as they already must be on
   the root filesystem, anyway
   opt/files/usr/sbin/setup allows also installation from boot CD to
   harddisk

  Usage

    1. After you unpacked the package into the fli4l tree, configure the
       files in config/ as usual.
    2. (Optional) If you have the hd package installed, make sure you
       also unpacked hd_update.zip and configured config/hd.txt. Note,
       that unpacking this archive will overwrite some files that coe
       with this package, so make backup copies if you want to keep the
       original files.
       There's an additional parameter for the updated files from the hd
       package: HDINSTALL_MOUNT_BOOT='no' (or 'rw' or 'ro')
       will override the setting of MOUNT_BOOT in config/base.txt. The
       reason for this is, that installtion to a harddisk requires
       MOUNT_BOOT='ro' or MOUNT_BOOT''rw', because the setup script needs
       to copy files from there to the harddisk. The config (which is
       located on the boot filesystem) file will be copied as well from
       there. So whatever you chose for MOUNT_OPT, if will also apply for
       the final installation on harddisk. Setting HDINSTALL_MOUNT_BOOT
       to something different however will override MOUNT_OPT, thus
       although you have chosen to mount boot during installation to
       harddisk, the boot partition will not be mounted afterwards.
    3. (Optional)
       If you want a special CD drive to be used, change the parameter
       "cd=auto" in img/syslinuxcd.cfg to the drive you'd like to be used:
         cd=/dev/hda if it's master on first IDE channel,
         cd=/dev/hdb if it's slave on first IDE channel,
         cd=/dev/hdc if it's master on second IDE channel,
         cd=/dev/hdd if it's slave on second IDE channel.
       Otherwise the CD will be sought for automaticaly in the following
       order: hdc, hdb, hdd, hda
    4. For Linux, run the script mkcd.sh, for Windows invoke mkcd.bat.
       These scripts will first perform as usual the check of the config
       files and create the files needed for creating a boot floppy.
       Note, that you will need a formatted 1.44MB floppy for this
       purpose
       From this boot floppy a floppy image will be read which is
       neccessary for bootable CDs. After the floppy image has been
       created, a CD iso image which comprises this floppy image as well
       as all files neccessary for starting the router software will be
       created in img/fli4l.iso.
    5. The script will then ask you, if you want to burn this image to a
       blank CD immediately, for details see the section "CD buring",
       below.

   If you are using Linux, and if you once started the mkcd.sh script,
   you can skip the (rather slow) generation of the boot floopy, provided
   you have root privileges, because in that case the next time you want
   to create a CD image, the former floppy image will be mounted as a
   loopback device and the modified configuration will be written to the
   image directly rather than first writing it to floppy and then reading
   the whole floppy to a file.
   However, if you have not root privileges or if you use Windows to
   create the image, you'll have no choice and the floppy will be
   generated each time you call the script. The reason for this is, that
   mounting files as loopback devices is usually allowed for the root
   user only in Linux on the one hand and accessing images in this way is
   not supported in Windws at all.
   There are three parameters that control the behaviour of these
   scripts:
   [-g] This forces the generation of a new floppy image, even if the
   former one could be used.
   [-s] This creates a "slow, stupid and secure" version of the syslinux
   loader. Use this if you have a somewhat broken machine and the usual
   way fails for you.
   [config-directory] This uses a different directory where config files
   are sought for rather then the default "config" directory.

  CD burning

   The creation of the CD image as well as the actual burning process is
   provided by means of third party software, see this section for
   details.
   To find out if your CD recorder is supported, check the list of
   supported drives on J”rg Schilly's page.
   After he script created a CD image, your system will be scanned by
   CDRECORD for drives, the list of drives will be presented to you, e.g.

   scsibus1:
        0,0,0   100) '        ' 'OME-W141        ' '1.40' Removable CD-ROM
        0,1,0   101) 'DM126D  ' 'DVDROM '01/01/29' '1.1C' Removable CD-ROM
        :
        :

   and you will be prompted to choose a drive from the list which should
   be used to burn the CD image to a blank medium. Please enter the
   three-digit id of your drive here, e.g. "0,0,0".
   If you do not want to burn the image, e.g. because you prefer to burn
   it with a piece of software of your choice, then abort this prompt by
   pressing Ctr-C. Otherwise prior to actual burning, a write simulation
   will be performed. If write simulation succeeds, you'll be prompted
   again for the actual write process, otherwise the script will fail.

  FAQs

   Q: I always get the error message "Windows was not able to gain exclusive
      access to the floppy drive" - so what's wrong ?
   A: Apparently you use windows 2000 or NT - the access restrictions are
      much more rigid that e.g. for win 98 or 95. I hav eno key why this
      happens sometimes, however what fails is the installation of the
      bootloader syslinux (that's the part thet make the floppy a bootable
      one). Fortunatelly I found out that does not happen neccessarily, 
      thus trying again and again and pressing the "Cancel" button of the
      dialog window that pops up should help. If someone kows a more
      elegant way to overcome this, lease send me a note: a.pogoda@web.de
      Furthermore this problem seems to happen less frequently if you call
      the script from inside a DOS box rather than just clicking on its icon
      (which however is more convenient - sure). Moreover you'll be able to
      call the script with optional parameters when doing so.
      Another solution to this is to use windows 95 or 98 (or XP - can
      someone prove this ?)

   Q: I always got the message ""Error writing or reading the
      floppy disk maybe the disk is full-try to select fewer options in
      configuration and try again" - what can I do ?
   A: Apparently you still use the very first version of the bootCD package.
      It suffered from the fact that the tool which is used to create the
      floppy image inside the mkcd script, apparently created the image
      in read-only mode the first time you invoked the script. 
      If you ivoke it again, the tool is unable to overwrite it.
      Either get a recent version of the bootCD package or delete the file
      "img/cd/boot.img" manually before invokation of mkcd.

   Q: There' splenty of space on the CD in contrast to boot floppy.
      Therefore I installed some 1000 optinal packages. Now there's
      a lack of storage space on the ramdisk when fli4l starts up -
      what's the way round this ?
   A: Obviously the size of the ramdisk is to small - you can adjust it
      with the "RAMSIZE" parameter in "config/base.txt".
      Most of the files from optional packages do not reside inseide the
      ramdisk that contains the rootfs but into a seperate one.
      Then symbolic links are created in the rootfs to these optional files.
      So in most cases it should be sufficient to set RAMSIZE to some larger
      value, e.g. 4096  (4MB), 8192 (8MB) etc.      
      If there's a need for quite a lot of links on the rootfs or if you
      installed packages which force files to reside inside the rootfs
      rather than the optional ramdisk, then even this can fail.
      For this  reason there's an optional switch "-l" to the mkcd script 
      which will cause the script to use a 32MB version of the root filesystem 
      instead of the default one.
      Of course you have to make sure that the amount of physical memory in
      the fli4l box you use is sufficiently large for the ramdisk, so you
      should have something like 64MB or more.
      If the default rootfs is too small for your needs, but the 32MB
      version is too large for your physical memmory, it's up on you to
      create a customized rootfs. You'll find valuable information on the
      fli4l homepage regarding this issue (http://fli4l.sf.net);

   Q: Why does the skript always create this nasty floppy image - 
      can I prevent it from doing so ?
   A: Yes and No - In the stoneage of PCs in the early 1980s there was no
      way to make a PC boot from a CD - mostly because CDs did no exist at
      all. So when the CDs came up and people wanted to boot from these just
      as they did with floppy disks, there was an agreement that the BIOS
      should read a special floppy image file on bootable CDs, load it into 
      memory and treat it just as it treats real floppies.
      For this reason the script needs to create a raw copy of a bootable
      floppy that will be located on the CD image afterwards.
      Finally the CD image wil be burned on a CD medium. When the PC boots
      from such a CD, it extracts the floppy image, maps it into RAM and 
      treats it as decribed above.
      There's no elegant way to access and modify such images under windows so 
      the script will always create by writing files onto a floppy and 
      creating a raw image afterwards.
      In Linux theres a concept called loopback-devices that allows for the
      mounting and access to such images. The drawback with this is that you
      must have superuser privileges to do so.
      So if you want to avod the long lasting procedure, make sure that you
      become root before you invoke the mkcd.sh script.
      Note however, that the very first time you invoke it, an floppy disk
      is neccessary regardless whether you're superuser or not, because a
      first image must be created. Subsequent invokation will then use the
      image created before.

   Q: Okay, if it's really neccessary to create a floppy image because it
      must reside o the CD, how is it possible that there fit more on the CD
      than there was space on the floppy ?
   A: The reason for this is, that not all of the files the fli4l box needs
      to startup must be located for the actal boot procedure.
      For this, onl the bootloader, the linux kernel and the root filesystem
      must be located on the floppy. The rest - that's the opt.tgz archive
      that contains all the optional files - may safely reside on the actual
      CD rather than in the floppy image.
      So the majority of a huge configuration is this archive - its size
      may vary from several hundreds of kB up to mayn MB.
      Fortunatelly ther's plenty of space on CDs, so this should be
      sufficient even if your configuration cause many optional files to be
      included into this archive.

  Third party software

   This package contains some third-party programs to create a CD image
   and to actually write it to a blank medium and to perform the script
   communication.
    1. CDRTOOLS - binary windows version 1.11a12 (Author: J”rg
       Schilling), see
         http://www.fokus.gmd.de/research/cc/glone/employees/joerg.schi
            lling/private
       for the lastest version. CDRTOOLS are under the GPL, see licence
       details.
       You'll find find binaries of mkisocd and cdrecord in the windows/
       directory. For a list of supported CD recorders search the linke
       above. For licence details, see "COPYING".
    2. GETVAR.EXE - form the citrix multi tools (Author: Eric Thurber),
       see
          http://www.oregonclassifieds.net
       for the lastest version.


  Links

   1. http://fli4l.sf.net/
   2. http://www.fokus.gmd.de/research/cc/glone/employees/joerg.schilling/private
   3. http://www.oregonclassifieds.net/

     _________________________________________________________________

   Author:   A. Pogoda
   Datum:    Feb. 25th 2002
   Modified: Apr. 05th 2002

