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  CD-Writing HOWTO
  Winfried Tr�mper <>
  v2.9.3, 23 July 2000

  This document explains how to write CD-ROMs under Linux.

  Table of Contents

  1. Introduction

     1.1 Copyright, license and terms of usage
     1.2 Availability
     1.3 Suggested readings
     1.4 Terminology ... lasers at maximum ... fire!
        1.4.1 Adaptor vs. Adapter
     1.5 Supported CD-writers
     1.6 Supported "features"
     1.7 Mailing Lists

  2. Setup the Linux-system for writing CD-ROMs

     2.1 Quickstart
        2.1.1 Special notes about SCSI CD-writers
        2.1.2 Special notes about CD-writers for the parallel port
        2.1.3 Compiling missing kernel modules (optional)
     2.2 Get the user software for burning CD-Rs
        2.2.1 Command line utilities
        2.2.2 Graphical user interfaces (optional)

  3. Burning CD-Rs

     3.1 Writing CD-ROMs (pure data)
        3.1.1 Creating an image of the later CD-ROM
        3.1.2 Test the CD-image
        3.1.3 Write the CD-image to a CD
     3.2 Writing audio CDs
        3.2.1 Writing audio CDs (TAO)
        3.2.2 DAO
     3.3 Mixed mode CD-ROMs

  4. Dear Winfried,...

     4.1 How sensitive is the burning process?
     4.2 Has file fragmentation a bad impact on the throughput?
     4.3 Is it possible to store the CD-image on an UMSDOS-filesystem?
     4.4 Isn't there some way to get around the ISO-9660 limitations?
     4.5 How to read the tracks from audio CDs?
     4.6 How to probe for SCSI devices after boot?
     4.7 Is it possible to make a 1:1 copy of a data CD?
     4.8 Can Linux read Joliet CD-ROMs? (obsolete answer)
     4.9 How do I read/mount CD-ROMs with the CD-writer?
     4.10 How to put even more data on the CD-R?
     4.11 How to make bootable CD-ROMs?
     4.12 How to make CD-ROMs writable like a hard disk?
     4.13 Is it possible to use several writers at once?
     4.14 What about Solaris, *BSD, AIX, HP-UX, etc.? Is my variant of Unix supported?
     4.15 Where to store the local configuration permanently?
     4.16 How can the CD-info be retrieved?
     4.17 What about re-writing
     4.18 How to create a multi-session CD?
     4.19 Should I use the SCSI adapter shipped with the writer?
     4.20 How to burn over the network?
     4.21 I hear a crack or click sound at the end of the each track.
     4.22 How can this be set up so that a user can burn CDs instead of always being root?
     4.23 Where do I get the "Yellow Book" and "Orange Book" standards?
     4.24 I've been searching for information on burning Video-CD under Linux.
     4.25 Which is easier to set up, IDE or SCSI?
     4.26 How can I overburn a CD using {cdrecord,cdrdao}?
     4.27 What will cdrecord do when it stops getting input from the pipe?
     4.28 Is there an equivalent to ignore=hdX for the ide-scsi emulation?
     4.29 How many times can you re-use CD-RW before they become faulty?
     4.30 Which format to choose for a platform independant CD-ROM?
     4.31 Is multi-session for audio tracks possible?
     4.32 What hardware resources do I need? Is an old Pentium enough?
  5. Troubleshooting

     5.1 It doesn't work: under Linux
     5.2 Error-message: No read access for 'dev=0,6,0'.
     5.3 It doesn't work: under DOS and friends
     5.4 SCSI errors during the burning phase
     5.5 Medium errors If cdrecord reports medium errors in the form of "Sense Key: ... Medium Error, Segment ...", then the medium is not empty. If you use CD-RW, then try to switch from blank=fast to the more reliable blank=all. If you use CD-R only, then make sure the CD-R has never seen a CD-writer before or try out discs from another manufacturer.
     5.6 Newly written CDs are not readable on some players.
     5.7 My scanner stopped working after I loaded the ide-scsi module

  6. Credits


  1.  Introduction

  Many people use Linux to burn CD-ROMs, because it is reliable and
  easy. No bluescreens while burning and no headaches about getting the
  right combination of hard- and software. It just works once properly
  set up. The CD-writing HOWTO explains the setup,  how to put data on
  the media and gives some interesting applications kindly submitted by
  the readers.

  1.1.  Copyright, license and terms of usage

  Copyright Winfried Tr�mper 1996-2000. All rights reserved.

  Redistribution and use, with or without modification, are permitted
  provided that the name of the author may not be used to endorse or
  promote products derived from this software without specific prior
  written permission. In this sense, translations are welcome and need
  not to be authorized by me.

  The author disclaims all warranties with regard to this document,
  including all implied warranties of merchantability and fitness for a
  certain purpose; in no event shall the author be liable for any
  special, indirect or consequential damages or any damages whatsoever
  resulting from loss of use, data or profits, whether in an action of
  contract, negligence or other tortious action, arising out of or in
  connection with the use of this document.

  Short: read and use at your own risk. No money-back guarantee.  If you
  want to understand why this document has always been under a very weak
  license and not under the gnu GPL or similar restrictive, then you
  should read this article from the german computer magazine c't:
  <> (currently only
  in German language).

  1.2.  Availability

  As the editor of this document I mostly sum up what other people
  report to me. I'm not a software developer nor an expert in hardware,
  so for specific problems with hard- or software you may want to ask
  somebody else.  What always makes sense is to report solutions for
  problems not already covered by the HOWTO to me.

  I get several hundred e-mails concerning the CD-Writing HOWTO each
  year.  So please be patient with me, as I cannot always answer within
  hours.  However, I read everything immediately and put you on my CDR-
  queue. Before you ask a question, please make sure you are aware of
  the newest version of this document; it is always available from

  1.3.  Suggested readings

  You may need the handbook for your Linux-distribution to learn about
  installing a new kernel. I'm really clueless about this issue when it
  comes to any other Linux distribution than my own.

  The CD-R FAQ <> is a general FAQ about
  compact-disk recordables (CD-R), CD-writers and the required software.
  As most CD-writers can be used to read CD-ROMs, too, you may want to
  read the Linux CD-ROM HOWTO, the Linux SCSI HOWTO and the Linux Kernel

  1.4.  Terminology ... lasers at maximum ... fire!

  CD-ROM stands for Compact Disc Read Only Memory, a storage medium
  utilizing an optical laser to sense microscopic pits on a colorful
  shimmering disk. The pits represent the bits of the information and
  are so petite that some billions of them fit on the disc. Thus a CD is
  a mass-storage medium.

  The term CD-R is a short form of CD-ROM recordable and refers to a CD
  that doesn't have those microscopic pits on its surface.  Thus it is
  empty. The CD-R has a special chemical film inside into which pits can
  be burned. This is done by giving the laser which normally just senses
  the pits a little bit more power so it burns the pits. This action can
  only be taken once on a CD-R. You can leave out some areas for later
  writing, creating a so called multi-session CD.

  The CD-ROM rewritable (short: CD-RW) was developed to work around the
  limitation of CD-R media. With a CD-RW burner the laser can do both,
  burn pits into the media and also melt the media back into its
  original state. This is possible, because the laser does not really
  burn holes into the media, which would get lost in a puff of smoke.  A
  decent analogy for the technique is an ice-hockey game: by driving
  over the ice, a players (laser) leave scratches in it. The pattern in
  the ice (media) is a recording of what happened on the ice during one
  round.  In between the periods of the game, the Zamboni cleaning car
  drives over the ice and fills the scratches by melting the very top
  layer of the ice.  (Zamboni is the brand name for cleaning cars in
  ice-hockey stadiums).  This way the pattern on the ice is cleared and
  a new round can begin. The scientific term for evaporating,
  condensing, melting and freezing is "phase change", thus the name
  "phase change devices" for CD-RW-writers.

  This HOWTO deals with the task of writing CD-Rs and CD-RWs.  Welcome
  on board, captain.

  1.4.1.  Adaptor vs. Adapter

  The the most frequent spelling within the kernel sources is adapter
  (adapter: 4283, adaptor: 154). Even more important, the parameters of
  module options and aliases are naturally affected, like in
  "scsi_hostadapter". So in order to achieve a consistent spelling
  throughout configuration examples and document text, I follow that
  convention regardless of the correct spelling.

  1.5.  Supported CD-writers

  USB CD-writers are currently not supported at all. Apart from that you
  can safely assume that most newer IDE/ATAPI- and SCSI-writers work
  under Linux. Newer drives are mostly MMC-compliant and are therefore
  supported. If the SCSI-version of a particular writer works, the
  IDE/ATAPI-version will most likely work and vice versa. However, some
  people want to get a warm and fuzzy feeling by reading the exact model
  of their writer in some sort of compatibility list.  That is the
  reason why I didn't throw the following list out of the HOWTO.  Here
  is a comprehensive summary of drives reported to work with cdrecord:

  Acer:           CDRW 4432A, CDRW 6206A, CD-R/RW 6X4X32, 8432A
  BTC:            BCE 621E (IDE)
  Compro:         CW-7502, CW-7502B
  Creative:       MK 4211, RW 4224E,
  Delta:          OME-W 141
  Dysan:          CRW-1622
  Elite:          Elite b444.41
  Goldstar:       CED-8041B
  Grundig:        CDR 100 IPW
  Guillemot:      Maxi CD-R 4X/8X
  HP:             SureStore 4020i, SureStore 6020i,
                  C4324, C4325
                  CD-writer+ 7100, 7200i, 7500e, 8100i, 8110i, 8200i Plus,
                             8250i, 9100i, 9110i, 9200e, 9210, 9300i, 9310i
  Hi-Val:         CDD 2242, CDD-3610,
  Iomega:         ZIPCD 4x650
  JVC:            XR-W 2001, XR-W 2010, XR-W 2040, XR-W 2042, XR-RW 2224,
                  YR 2626
  Kiss:           CDRW (no model given)
  Kodak:          PCD 200, PCD 225, PCD 260, PCD 600
  Matsushita:     matsushita is the japanese name for panasonic, please see there
  Memorex:        CRW-620, CDR-622, CRW-1622, CRW-2224, CDRW-4420
  Microboards:    PlayWrite 2000, PlayWrite 4000 RW, PlayWrite 4001 RW
  MicroNet:       MasterCD Plus 4x4, MasterCD Plus 4x6
  Mitsubishi:     CDRW-226
  Mitsumi:        CR-2401-TS, CR-2600 TE,  CR-2801 TE,
                  CR-4801 TE, CR-4802 TE,  CR-4804 TE
  Nomai:          680.RW
  Olympus:        CDS 615E, CDS 620E
  Optima:         DisKovery 650 CD-R
  OTI:            CDRW 965, CDRW 975 (Socrates 1.0)
  Panasonic:      CW-7285, CW-7502, CW-7503, CW-7582
  Philips:        CDD-521/10, CDD-522,
                  CDD-2000, CDD-2600, CDD-3600, CDD-3610, CDD 4201
                  PCA 267cr, PCA 460 RW, PCRW 404,
                  Omniwriter 26, Omniwriter 26A,
  Pinnacle:       RCD-100, RCD-1000, RCD-5020, RCD-5040
  Pioneer:        DW-S114X
  Plasmon:        CDR 480, CDR 4220, RF-4100, RF-4102, CDR 4400
  Plextor:        CDR PX-24 CS, PX-412 C, PX-R412 C
                  PX-R 810Ti, PX-R 820T, PX-W 4220Ti, PX-W 8220T, PX-W 8432T
                  Plexwriter RW 4/2/20
  Procom:         PCDR 4
  REC:            820s
  Ricoh:          RO-1420C+, MP 1420C, MP 6200S, MP 6201S, MP 7040A, MP-7060A
  Samsung:        SW-204
  Sanyo:          CRD-R24S
  Smart and
  Friendly:       CD-RW 226, CD-R 1002, CD-R 1002/PRO, CD-R 1004,
                  CD-R 2004, CD-R 2006 PLUS, CD-R 2006 PRO, CD-RW 2224,
                  CD-R 4000, CD-R 4006, CD-R 4012, CD-RW 4424A
                  CD-R 8020, CD-R 8220
  Sony:           CDRX 100E, CDRX 120E, CDRX 140S-RP,
                  CDU 920S, CDU 924, CDU 926S, CDU 928E, CDU 948S
  Taiyo Yuden:    EW-50
  TEAC:           CD-R50S, CD-R55S, CDR-55S, CDR-55K,
                  CDR-56S-400, CD-R56S-600, R56S-614
  Traxdata:       CRW 2260,
                  CDR 4120, CDR 4120 Pro, CDRW 4260, CDRW 4424, CDR 4800
  Turtle Beach:   2040R
  Waitec:         wt 2036, wt 2444ei
  WPI (Wearnes):  CDRW-622, CDR-632P
  Yamaha:         CDR-100, CDR 102, CDR-200, CDR-200t, CDR-200tx
                  CDR-400, CDR-400c, CDR-400t, CDR-400tx, CDR-400Atx
                  CDW-2216E, CRW-2260, CRW-2260t,
                  CRW-4250tx, CRW-4260t, CRW-4260tx, CRW-4261, CRW-4416S,
                  CRW-6416S, CRW-8424E

  The detailed list of models which have been reported to work or not to
  work under various Unix-like operating systems is available online
  from <>.

  If your hardware isn't supported you can still use Linux to create an
  image of the CD. You may wish to do so because most burning software
  for DOS does not deal with RockRidge-extensions (Unix-like filesystems
  on CD-ROM). In a second step, you can use DOS or Macintosh software to
  write the image to the CD-R.

  1.6.  Supported "features"

  Two There are two classes of utilities: the hardware drivers and the
  data-formatters. The hardware drivers support the following features:

       Supported Feature   cdwrite-2.1     cdrecord-1.6    cdrdao
       IDE/ATAPI           yes             yes             yes
       Parallel Port       no              yes             yes
       CD-RW               no              yes             yes
       Audio CD            yes             yes             yes
       Data CD-ROM         yes             yes             partial
       Multisession        partial         yes             no
       TAO (track at once) yes             yes             yes
       DAO (disk at once)  no              partial         yes
       packet writing      no              no              no

  cdwrite is unmaintained software referenced only for completeness.
  Please use cdrecord instead, as it supports a wider range of hardware
  and has significantly more features. The main benefit of cdrdao is the
  ability to create audio CDs without two seconds of silence between the
  tracks (writing in disk-at-once (DAO) mode).

  The tools classified as "data-formatters" organize the data on the
  media ("put a filesystem on it").

       Feature         mkisofs         mkhybrid        mkvcdfs
       ISO 9660        yes             yes             no
       RockRidge       yes             yes             no
       El Torito       yes             yes             no
       HFS             no              yes             no
       Joliet          yes             yes             no
       Multisession    yes             yes             no
       CD-Extra        yes             yes             no
       Video-CD        no              no              yes

  The most obvious difference between the ISO 9660 filesystem compared
  to the ReiserFS or Extended-2 filesystem is: you can't modify files
  once they are written.  Other limitations of the ISO-9660-filesystem

  �  only 8 levels of sub-directories allowed (counted from the top-
     level directory of the CD)

  �  maximum length for filenames: 32 characters

  �  650 MB capacity

  RockRidge is an extension to allow longer filenames and a deeper
  directory hierarchy for the ISO-9660 filesystem. When reading a CD-ROM
  with RockRidge extensions under Linux, all the known properties of
  files like owner, group, permissions, symbolic links appear ("feels
  like a Unix filesystem").  These extensions are not available when
  reading the CD-ROM under DOS or the heterogenous Windows-family of
  operating systems.

  El Torito can be used to produce bootable CD-ROMs. For this feature to
  work, the BIOS of your PC must support it. Roughly speaking, the first
  1.44 (or 2.88 if supported) Mbytes of the CD-ROM contains a floppy-
  disk image supplied by you. This image is treated like a floppy by the
  BIOS and booted from. (As a consequence, while booting from this
  virtual floppy, your original drive A: (/dev/fd0) may not be

  HFS lets a Macintosh read the CD-ROM as if it were an HFS volume (the
  native filesystem for MacOS).

  Joliet brings long filenames (among other things) to newer variants of
  Windows (95, 98, NT). However, the author knows of no tool that allows
  long filenames under plain DOS or Windows 3.11.

  Video-CDs can be directly played on DVD-devices.

  Section 2.8 lists the availability of the mentioned software.

  1.7.  Mailing Lists

  If you want to join the development team (with the intention to
  actively help them), send e-mail to
  and put the word subscribe in body of the message.

  2.  Setup the Linux-system for writing CD-ROMs

  This section applies to the following types of CD-writers: SCSI,
  IDE/ATAPI and the devices for the parallel port. USB CD-writers are
  not supported as of May 2000. Non-SCSI writers require compatibility
  drivers, which make them appear as if they were real SCSI devices. On
  the one side such a unifying strategy is easy ("everything is SCSI"),
  because on the application level you can share your knowledge with
  other users regardless of their kind of CD-writer. On the other side,
  you have to reconfigure applications like audio CD players or the
  mount utility to reflect the change of the driver name. For example,
  if you accessed your ATAPI CD-writer through the device file /dev/hdc
  before, you will have to access it through /dev/scd0 after activating
  the SCSI compatibility drivers.

  Once you succeed setting up your hardware and the rest of your Linux-
  system, the command cdrecord -scanbus shows you a list of devices on
  your SCSI busses.  The goal of this section is to guide you in setting
  up your Linux-system, so that you finally end up seeing something

       shell> cdrecord -scanbus
       Cdrecord release 1.7a1 Copyright (C) 1995-1998 J�rg Schilling
             0,0,0) 'Quantum ' 'XP34300         ' 'F76D' Disk
             0,1,0) 'SEAGATE ' 'ST11200N        ' '8334' Disk
             0,2,0) *
             0,3,0) 'TOSHIBA ' 'MK537FB/        ' '6258' Disk
             0,4,0) 'WANGTEK ' '5150ES SCSI 36  ' 'ESB6' Removable Tape
             0,5,0) 'EXABYTE ' 'EXB-8500-85QUE  ' '0428' Removable Tape
             0,6,0) 'TOSHIBA ' 'XM-3401TASUNSLCD' '3593' Removable CD-ROM
             0,7,0) *
             1,0,0) 'Quantum ' 'XP31070W        ' 'L912' Disk
             1,1,0) *
             1,2,0) *
             1,3,0) 'TEAC    ' 'CD-R55S         ' '1.0H' Removable CD-ROM
             1,4,0) 'MATSHITA' 'CD-R   CW-7502  ' '4.02' Removable CD-ROM
             1,5,0) *
             1,6,0) 'YAMAHA  ' 'CDR400t         ' '1.0d' Removable CD-ROM
             1,7,0) *

  The example was provided by J�rg Schilling and shows a total of four
  CD-writers. Please note that -scanbus also reports other devices, e.g.
  regular CD-ROMs and hard disk drives. The last column gives the SCSI
  description of the device, from which you cannot clearly distinguish
  ordinary CD-ROM drives from those with burning capability. But the
  product identification (middle column) often has hints about the
  feature in form of a R, -R or -RW.

  2.1.  Quickstart

  This section is an attempt to provide an fast and easy description of
  the configuration. Not all possible setups are covered, but please go
  on and try it out anyways. First of all, check the Linux kernel
  version printed by the command "uname -r".  It should be something
  like 2.0.X or 2.2.Y, where X is higher than 36 and Y is higher than
  11. If you run older versions or the so called development kernels,
  you are on your own. Installing a new kernel is as much work as fixing
  an old one, so I have removed all hints you need for buggy kernels.

  The listing below shows a set of commands you could start with. The
  commands create device file entries under /dev unless they already

       test `whoami` = 'root' || echo "You must be root to execute the commands."
       cd /dev/
       umask -S u=rwx,g=rwx,o-rwx
       [ -f loop0 ] \
           || ./MAKEDEV loop \
           || for i in 0 1 2 3 4 5 6 7; do mknod loop$i b 7 $i; done
       [ -f sg0 -o -f sga ] \
           || ./MAKEDEV sg \
           || for i in 0 1 2 3 4 5 6 7; do mknod sg$i  c 21 $i; done

  Hardware access is usally implemented through device files under
  Linux.  So before any other thing you make sure those files do exists
  in the directory /dev. Still nobody could give me a compelling reason
  why this has not been automated through techniques like the device
  filesystem (devfs). The devfs is available for years know, brings a
  safer (!) and a far clearer naming of devices and makes the device
  entries appear automatically under /dev. Some prominent people argue
  devfs is not the perfect solution, but they do not come up with
  anything better, not even something comparable and last but least
  nothing available and tested now. Lets start to use devfs, so I can
  remove the above commands from this document. (

  Next thing to ensure is, that the Linux kernel is equiped with the
  necessary drivers. The following commands check various files for the
  presence of drivers in the running Linux kernel. Usally the command
  "cdrecord -scanbus" should trigger an automatic loading of all
  drivers. In case a driver is not present in the kernel afterwards, it
  is reported and the modularized driver (module) is manually loaded
  through insmod.

       test `whoami` = 'root' || echo "You must be root to execute the commands."
       cdrecord -scanbus > /dev/null
       if ! (pidof kerneld || test -f "/proc/sys/kernel/modprobe"); then
           echo "Neither kerneld nor kmod are running to automatically load modules".
       report_no_autoload() {
           echo "Ensure the module $1 is loaded automatically next time."
       if test ! -f "/proc/scsi/scsi"; then
           report_no_autoload scsi_mod  &&  insmod scsi_mod
       if ! grep "^........ sg_" /proc/ksyms > /dev/null; then
           report_no_autoload sg  &&  insmod sg
       if ! grep "^........ sr_" /proc/ksyms > /dev/null; then
           report_no_autoload sr_mod  &&  insmod sr_mod
       if ! grep "^........ loop_" /proc/ksyms > /dev/null; then
           report_no_autoload loop  &&  insmod loop
       if ! grep iso9660 /proc/filesystems > /dev/null; then
           report_no_autoload iso9660  &&  insmod iso9660
       echo "The following is only needed for IDE/ATAPI CD-writers."
       if ! grep ide-scsi /proc/ide/drivers > /dev/null; then
           report_no_autoload ide-scsi  &&  insmod ide-scsi
       cdrecord -scanbus

  Please read the next chapter if insmod complains about missing module
  files.  If you are in text mode (console), the loading of modules may
  cause some messages to be printed on your screen. If you are in
  graphics mode (X11, KDE, Gnome), you can recall these messages with
  the command dmesg.

  There are several ways to load the modules next time you start up your
  Linux system:

       (1) Put the relevant insmod command into the startup sequence
           (a shell script named rc.local or equivalent).
       (2a) Run kerneld or kmod and
       (2b) configure them in /etc/modules.conf (to be more precise,
            you configure the utility modprobe, which is called by the daemons)

  People with a SCSI-writer can skip the rest of this section, because
  cdrecord will most likely already detect their hardware. If not, then
  please send me an email with some information about your setup, so I
  can improve the section about SCSI-writers.

  Now to the people with CD-writers for IDE/ATAPI.  As written in the
  previous chapter, you have to load the compatibility driver ide-scsi.
  But this driver can only access your CD-Writer if no other driver has
  already done so. In other words, you have to tell the regular IDE
  driver to leave your CD-writer unrecognized, so the ide-scsi driver
  can grab it.

       hda = IDE bus/connector 0 master device
       hdb = IDE bus/connector 0 slave  device
       hdc = IDE bus/connector 1 master device
       hdd = IDE bus/connector 1 slave  device

  The table above shows the relation of device file names and the
  placing of devices on the IDE busses. The device file name
  representing your CD-Writer has to be passed to the driver in the
  Linux kernel. Example: hdb=ide-scsi.  Such a setting should be added
  to lilo.conf or chos.conf if the driver is statically compiled into
  your kernel, which seems to be the most common setup. If you need to
  pass more than one parameter to the kernel, then seperate them with
  spaces (like shown in the chos example). The next two listings show
  example configurations containing more lines than just the relevant
  append-line. Please note the append- and cmdline-entries are image-
  specific (ie. don't add them immediatly at the top).


       linux "Linux 2.1.14" {
               cmdline= root=/dev/hda5 readonly hdb=ide-scsi

  If the driver for IDE/ATAPI CD-ROMs is loaded as a module, then the
  above won't make any difference to you, but make sure you include the
  options-line from the next listing. The last three lines of that
  listing are generally suggested to further automate the loading of the
  required modules.

       options ide-cd ignore=hdb            # tell the ide-cd module to ignore hdb
       alias scd0 sr_mod                    # load sr_mod upon access of scd0
       #pre-install ide-scsi modprobe imm    # uncomment for some ZIP drives only
       pre-install sg     modprobe ide-scsi # load ide-scsi before sg
       pre-install sr_mod modprobe ide-scsi # load ide-scsi before sr_mod
       pre-install ide-scsi modprobe ide-cd # load ide-cd   before ide-scsi

  If your CD-writer is the only CD-ROM attached to your machine, then
  remember you have to access the CD-ROM in the writer through the
  device file /dev/scd� where �=0,..,8. You may want to change the
  symbolic name cdrom to point to the new device file name. The listing
  below shows the command to achieve this with the example scd0.

       cd /dev && rm cdrom && ln -s scd0 cdrom

  If your CD-writer and CD-ROM-drive are two different devices, then
  don't change the cdrom symlink.

  2.1.1.  Special notes about SCSI CD-writers

  Please make sure that your writer is recognized by the BIOS of your
  SCSI hostadaptor card. Every SCSI hostadaptor scans the SCSI bus after
  power on and reports all devices found connected to the bus. The
  report includes the SCSI ID of the devices and their product label. It
  makes no sense to proceed unless your CD writer is listed in that

  If you plan to connect your SCSI device through the parallel port (not
  to confuse with the IDE drives for the parallel port), you need a
  special active cable and a special kernel driver. Read
  <> to learn more about this

  2.1.2.  Special notes about CD-writers for the parallel port

  I have no clue about this, sorry. Please read
  <> or your local file

  2.1.3.  Compiling missing kernel modules (optional)

  You don't need to read this section if you hardware is already
  sucessfully recognized and configured by the previously described
  configuration steps.

  The Linux kernel can be equipped with drivers for various features.
  You can compile the drivers into the kernel image statically or you
  can compile them as a module for on-demand loading. The last method is
  preferred for drivers not essential for bringing your Linux-system
  into life, because your kernel will be smaller and faster then.
  However, some drivers are essential for the system to come up and you
  shouldn't compile them as a module. Example: if your system lives on
  an IDE hard disk, you must have the driver for IDE hard disks in the
  kernel -- not as a module.

  There are three different types of CD-writers: SCSI, IDE/ATAPI and
  external writers that work through the parallel port. The table shows
  how to configure the Linux kernel for those hardware types. The first
  column of the table is the section of the kernel configuration menu,
  where you can find the setting. The second column is the description
  of the feature (taken from the kernel configuration menu, too). The
  third column gives the name of the resulting module. The columns named
  SCSI, IDE and PP contain the necessary options for the associated
  hardware (PP = parallel port).

       Sect.  Description                 Module   SCSI  IDE   PP
       BLOCK  Enhanced IDE/MFM/RLL...                     Y
       BLOCK  IDE/ATAPI CDROM             ide-cd          M
       BLOCK  SCSI emulation support      ide-scsi        M
       BLOCK  Loopback device             loop       M    M     M

       PARIDE Parallel port IDE device    paride               Y/M
       PARIDE Parallel port ATAPI CD-ROMs                       M
       PARIDE Parallel port generic ATAPI                       M
       PARIDE (select a low-level driver)                       Y

       SCSI   SCSI support                scsi_mod  Y/M  Y/M
       SCSI   SCSI CD-ROM support         sr_mod    Y/M  Y/M
       SCSI     Enable vendor-specific               Y    Y
       SCSI   SCSI generic support        sg        Y/M  Y/M
       SCSI   (select a low-level driver)            Y

       FS     ISO 9660 CDROM filesystem   iso9660   Y/M  Y/M   Y/M
       FS     Microsoft Joliet cdrom...   joliet     Y    Y     Y

  Y stands for yes and means you should put the beast into the kernel.
  M stands for module and means you should or must compile this feature
  as a module.  Y/M gives you the option to decide between either (order
  indicates choices with less potential problems). Empty settings don't
  need to be modified and not changing them increases the chance that
  the resulting kernel will work for you (if it did before...).
  Especially in environments where SCSI and ATAPI devices are mixed, you
  better build most things as modules.

  Compiling loopback device is optional.  It allows you to test the
  image before writing it to the media. If you want to be able to read
  CD-ROMs, you need support for the ISO 9660 filesystem. This driver
  automatically includes RockRidge Extensions. The Microsoft Joliet CD-
  ROM extensions have to be explicitly added to the ISO 9660 filesystem.
  In any case, you need a low-level driver for your hardware. Low-level
  refers to the driver, which interacts directly with the hardware.  For
  SCSI and the parallel port, there are a lot of low-level drivers

  Installing the resulting Linux-kernel is beyond the scope of this
  HOWTO. Please consult the documentation of your Linux-distribution.
  Users of RedHat Linux be aware that you have to compile in the
  features "Ramdisk support" and "Initial ramdisk". Furthermore, you
  have to generate a new ramdisk with the new modules by issuing a
  command like "mkintrd --preload ide-cd initrd-2.2.14.img  2.2.14".

  2.2.  Get the user software for burning CD-Rs

  A more detailed survey of tools related to produce CD-ROMs is
  available from

  2.2.1.  Command line utilities

  One of the following packages are required to generate images of CD-Rs
  (only required for data CD-ROMs):

       <> (mkisofs)

       <> (mkhybrid)

  To write images to the CD-R, you need one of the following software

       <> (cdrecord)

       <> (cdrdao)

       <> (mkvcdfs)

  Don't trust the man page of old versions of mkisofs which state you
  need version 1.5 of cdwrite. Just use cdrecord and you are fine.
  Please note that newer versions of cdrecord ship with an enhanced
  version of mkisofs and some extra tools in the subdirectory misc/
  (readcd, isosize) not found elsewhere.

  2.2.2.  Graphical user interfaces (optional)

  Front-ends are really front-ends under Linux. That means, you still
  have to install the command-line utilities, but you access them in a
  better looking manner.

  X-CD-Roast is a program package dedicated to easy CD creation under
  Linux. It combines command line tools like cdrecord and mkisofs into a
  nice graphical user interface.


  BurnIT is a JAVA front-end to cdrecord, mkisofs and cdda2wav-0.95
  making it a complete package for burning CDs on the Unix platform. It
  is available from


  CD-Tux is a character based frontend for the programs mkisofs and
  cdrecord. "It creates an easy to use enviroment for doing almost
  anything to a CD in full color through the use of the (in)famous
  NCURSES Library. And it does all this whith an executable of under


  3.  Burning CD-Rs

       "If to smoke you turn I shall not cease to fiddle while you
       burn." (Roman emperor Nero about burning his own classic-
       CDs, AD64. He misunderstood it completely and burned Rome

  Writing CD-ROMs consists of two steps under Linux:

  �  packaging the desired data (files, music or both) into files with
     special formats

  �  writing the data from the files to the CD-R with the utility

  This chapter describes the steps for data and audio CDs in greater

  3.1.  Writing CD-ROMs (pure data)

  Note that collecting the data to put onto a CD usually takes longer
  than one expects. Consider that missing files cannot be added once the
  CD is written and fixated. This is also true for CD-RW, which can
  currently only be rewritten as a whole. Using the multi-session
  feature is no option for single files, as it consumes much space for a
  new complete table of contents (TOC). UDF is not ready yet for Linux.

  Also keep in mind that a certain amount of the free space of a CD is
  used for storing the information of the ISO-9660-filesystem (usually a
  few MB).  620 MB data will always fit on a 650 MB CD-R.

  3.1.1.  Creating an image of the later CD-ROM

  Before any storage medium (e.g. floppy disk, hard disk or CD) can be
  used, it must get a filesystem (DOS speak: get formatted).  The
  filesystem is responsible for organizing and incorporating the files
  that should be stored on the medium.

  The usual utilities for creating filesystems on hard disk partitions
  write an empty filesystem onto them, which is then mounted and filled
  with files by the users as they need it. A writable CD is only
  writable once so if we wrote an empty filesystem to it, it would get
  formatted and remain completely empty forever. This is also true for
  rewritable media as you cannot change arbitrary sectors yet; you must
  erase their whole content.

  So what we need is a tool that creates the filesystem while copying
  the files to the CD. This tool is called mkisofs.  A sample usage
  looks as follows:

       mkisofs  -r   -o cd_image   private_collection/
                     `---------'   `-----------------'
                          |               |
                 write output to   take directory as input

  The option '-r' sets the permissions of all files to be public
  readable on the CD and enables RockRidge-extensions. You probably want
  to use this option unless you really know what you're doing (hint:
  without '-r' the mount point gets the permissions of

  mkisofs will try to map all filenames to the 8.3 format used by DOS to
  ensure the highest possible compatibility. In case of naming conflicts
  (different files have the same 8.3 name), numbers are used in the
  filenames and information about the chosen filename is printed via
  STDERR (usually the screen). Don't panic: Under Linux you will never
  see these odd 8.3 filenames because Linux makes use of the Rock Ridge
  extensions which contain the original file information (permissions,
  filename, etc.).

  Remeber do use the Option -J (MS Joliet extensions) or use mkhybrid if
  you want to generate a more Windows-friendly CD-ROM. For HFS CD-ROMS
  used on the Macintosh, you better read the man-page of mkisofs' bigger
  sister mkhybrid for details on various options.

  Now you may wonder why the output of mkisofs is not directly sent to
  the writer device. There are three reasons:

  �  mkisofs knows nothing about driving CD-writers.

  �  You may want to test the image before burning it.

  �  On slow machines it would not be reliable (see section 4.).

  There is a method to write a CD-R in one go, which will be described

  One also could think of creating an extra partition and writing the
  image to that partition instead to a file. I vote against such a
  strategy because if you write to the wrong partition due to a typo,
  you can lose your complete Linux system. Read: that happened to me...
  Furthermore, it is a waste of disk space because the CD-image is
  temporary data that can be deleted after writing the CD. However,
  using raw partitions saves you the time for deleting files of 650 MB

  3.1.2.  Test the CD-image

  Linux has the ability to mount files as if they were disk partitions.
  This feature is useful to check that the directory layout and file
  access permissions of the CD image matches your wishes. Although media
  is very cheap today, the writing process is still time consuming, and
  you may at least want to save your time by doing a quick test.

  To mount the file cd_image created above on the directory /cdrom, give
  the command

       mount -t iso9660 -o ro,loop=/dev/loop0 cd_image /cdrom

  Now you can inspect the files under /cdrom -- they appear exactly as
  they were on a real CD. To umount the CD-image, just say umount
  /cdrom. (Warning: On Linux kernels prior to 2.0.31 the last file on
  /cdrom may not be fully readable. Please use a more recent kernel like
  2.0.36. The option -pad for cdrecord applies to audio CDs only and the
  option -pad for mkisofs requires a patch, which is as much work to
  apply than to upgrade to a bug-free Linux kernel.)


       Some ancient versions of mount are not able to deal with
       loopback devices. If you have such an old version of mount,
       then upgrade your Linux-system.  Several people have already
       suggested putting information about how to get the newest
       mount utilities into this HOWTO. I always refuse this.  If
       your Linux distribution ships with an ancient mount, report
       it as a bug.  If your Linux distribution is not easily
       upgradable, report it as a bug.

       If I include all the information that is necessary to work
       around bugs in badly designed Linux distributions, this
       HOWTO would be a lot bigger and harder to read.

  3.1.3.  Write the CD-image to a CD

  This section only covers writing data CDs in TAO mode, because it is
  the most frequently used mode for data. For more information about the
  differences of TAO and DAO, please see the chapter about audio CD-Rs.
  If you use DAO mode with the tool cdrdao, then remember to add a dummy
  audio track at the end of the TOC file (see the README).

  Not much more left to do. If you haven't already tried, it's a good
  time for the command

       cdrecord -scanbus

  This will tell you to which SCSI device your CD-writer is attached to.
  All other methods of guessing the information printed so nicely by
  cdrecord have been removed from the HOWTO.

  Before showing you the last command, let me warn you that CD-writers
  want to be fed with a constant stream of data. So the process of
  writing the CD image to the CD must not be interrupted or a corrupt CD
  will result. It's easy to interrupt the data stream by deleting a very
  large file. Example: if you delete an old CD-image of 650 Mbytes size,
  the kernel must update information about 650,000 blocks on the hard
  disk (assuming you have a block size of 1 Kbyte for your filesystem).
  That takes some time and is very likely to slow down disk activity
  long enough for the data stream to pause for a few seconds.  However,
  reading mail, browsing the web, or even compiling a kernel generally
  will not affect the writing process on modern machines.

  Please note that no writer can re-position its laser and continue at
  the original spot on the CD when it gets disturbed.  Therefore any
  strong vibrations or other mechanical shocks will probably destroy the
  CD you are writing.

  When you are mentally prepared, dress up in a black robe, multiply the
  SCSI-id of the CD-writer with its SCSI-revision and light as many
  candles, speak two verses of the ASR-FAQ (newsgroup
  alt.sysadmin.recovery) and finally type:

       shell> SCSI_BUS=0   # taken from listing 1 "scsibus0:"
       shell> SCSI_ID=6    # taken from listing 1 "TOSHIBA XM-3401"
       shell> SCSI_LUN=0
       shell> cdrecord -v speed=2 dev=$SCSI_BUS,$SCSI_ID,$SCSI_LUN \
                          -data  cd_image

       # same as above, but shorter:
       shell> cdrecord -v speed=2 dev=0,6,0  -data  cd_image

  For better readability, the coordinates of the writer are stored in
  three environment variables with natural names: SCSI_BUS, SCSI_ID,

  If you use cdrecord to overwrite a CD-RW, you must add the option
  "blank=..." to erase the old content.  Please read the man page to
  learn more about the various methods to blank the CD-RW.

  In times where everybody except me owns a 400 Mhz machine, people feed
  the output of mkisofs directly into cdrecord:

       shell> IMG_SIZE=`mkisofs -R -q -print-size private_collection/  2>&1 \
       | sed -e "s/.* = //"`
       shell> echo $IMG_SIZE
       shell> [ "0$IMG_SIZE" -ne 0 ] && mkisofs -r  private_collection/  \
       |cdrecord  speed=2  dev=0,6,0
                   tsize=${IMG_SIZE}s  -data  -
       #       don't forget the s --^         ^-- read data from STDIN

  The first command is an empty run to determine the size of the image
  (you need the mkisofs from the cdrecord distribution for this to
  work). You need to specify all parameters you will use on the final
  run (e.g. -J or -hfs).  Maybe your writer does not need to know the
  size of the image to be written, so you can leave this dry run out.
  The printed size must be passed as a tsize-parameter to cdrecord (it
  is stored in the environment variable IMG_SIZE). The second command is
  a sequence of mkisofs and cdrecord, coupled via a pipe.


  3.2.  Writing audio CDs

  Writing audio CDs is very similar to the steps described above for
  data CDs. You can choose between two techniques: DAO or TAO.  TAO
  (track at once) is less suitable for music, because you will hear
  clicks between the individual tracks. It is described first anyways,
  because it is a little bit easier to deal with and DAO is not
  available for all drives yet.

  The main difference compared to writing data CD-Rs is the format of
  the images. ISO-9660 (or whatever filesystem you prefer) would not be
  suitable, because no audio CD player is able to deal with filesystems.
  Instead the audio data must be writen as "16 bit stereo samples in PCM
  coding at 44100 samples/second (44.1 kHz)".

  One utility to convert your sound files into the required format is
  sox.  Its usage is straightforward:

       shell> sox  killing-my-software.wav  killing-my-software.cdr

  This command would convert the song killing-my-software from the WAV-
  format into the CDR audio-format. See the man page for sox for more
  details about formats and filename-extensions sox recognizes. Because
  the output of the manual conversion takes up much disk space, it was
  made a built-in feature of cdrecord for the sound formats WAV and AU.
  So as long as your sound files have the extensions .wav or .au (and
  the sample rate "stereo, 16 bit, 44.1 kHz"), you can use them as audio
  tracks without manual conversion into the CDR format. However,
  cdrecord requires the size of the sound data to be a integer multiple
  of 2352 and to be greater than 705,600 bytes, which is not fullfilled
  for some WAV files. For such files the usage of sox is needed to pad
  the audio data up to 2352 bytes.

  3.2.1.  Writing audio CDs (TAO)

  An audio CD consists of audio tracks, which are organized as separate
  images when using TAO mode. So if you want to have ten tracks on your
  CD, you have to make ten images.

  Cdrecord writes CD images as audio tracks if the option -audio is
  specified. The other options are identical to those used for writing
  data-CDs (unless you have very special requirements). These three
  examples all do the same thing, but read the tracks from different
  sound file formats:

       shell> cdrecord -v speed=2 dev=0,6,0  -audio  track1.cdr track2.cdr...
       shell> cdrecord -v speed=2 dev=0,6,0  -audio  track1.wav track2.wav...
       shell> cdrecord -v speed=2 dev=0,6,0  -audio

  By doing this, you will produce an audio CD which has a 2 seconds of
  pause between audio tracks.  One notable format not directly readable
  by cdrecord is MPEG Layer 3. To convert files in this format to the
  CDR-format, you can use the command "mpg123 --cdr - track1.mp3 >
  track1.cdr".  The option --cdr ensures the track is encoded in the
  required format (see above). Older versions of mpg123 require -s
  instead of the plain - to write to stdout.  The other direction
  (converting from WAV to MPEG) can be done with LAME for WAV-files
  (extract the track with cdda2wav from the audio CD and encode it into
  MP3 with the help of LAME).

  To create a CD-R from a whole bunch of MP3-files, you can use the
  following command sequence:

       for I in *.mp3
           mpg123 --cdr - "$I" | cdrecord -audio -pad -nofix -
       cdrecord -fix

  Depending on the speed of your machine, you may want to slow down
  writing to "speed=1" (cdrecord option). If you use "speed=4", your
  machine must be able to play the MP3-file at quadruple speed. mpg123
  consumes much CPU-time! If you are in doubt, try an empty run with
  -dummy (keeps the laser switched off).

  3.2.2.  DAO

  If you want to get rid of the pauses between the audio tracks, you
  have to use disk-at-once (DAO) recording versus the (individual)
  track-at-once (TAO) recording described above. Support for DAO is
  currently most advanced in cdrdao. Please see its homepage for

  If you master the CD in DAO mode, then you use a monolithic image
  (sound file) and control track information with a configuration file.

       FILE "live.wav" 0 5:0:0
       INDEX 3:0:0
       FILE "live.wav" 5:0:0 5:0:0
       FILE "live.wav" 10:0:0 5:0:0
       INDEX 2:0:0

  3.3.  Mixed mode CD-ROMs

  There is not much to say about this topic. Just indicate the type of
  the (subse quent) images with the options -data and -audio. Example:

       cdrecord  -v dev=0,6,0  -data  cd_image  -audio  track*.cdr

  4.  Dear Winfried,...

  This is the section usually known as "frequently asked questions with
  answers". If you have a problem with your partner, kids or dog, just
  send it in, as long as it is related to writing CD-Rs or is otherwise

  4.1.  How sensitive is the burning process?

  Test it. Use the option -dummy to do an empty run of cdrecord. Do
  everything you would do otherwise and watch if the burning process

  If you feed cdrecord directly from mkisofs, then disk intensive
  processes such as updating the locate database lower the maximum flow
  rate and may corrupt the CD. You better check such processes are not
  started via cron, at or anacron while you burn CD-Rs on older

  4.2.  Has file fragmentation a bad impact on the throughput?

  Fragmentation of files is usually so low that its impact isn't
  noticed. However, you can easily construct pathological cases of
  fragmentation, which lower the throughput of your hard disks under 100
  kbytes/second. So don't do that. :-) Yes, files on a hard disk get
  fragmented over the years. The faster, the fuller the filesystem is.
  Always leave 10% or 20% free space, and you should run fine with
  respect to writing CD-Rs.

  If you're uncertain then look at the messages printed while booting.
  The percentage of fragmentation is reported while checking the
  filesystems. You can check for this value with the very dangerous

       shell> e2fsck -n  /dev/sda5        # '-n' is important!
       [stuff deleted -- ignore any errors]
       /dev/sda5: 73/12288 files (12.3% non-contiguous)

  In this example the fragmentation seems to be very high -- but there
  are only 73 very small files on the filesystem. So the value is not

  There is an experimental utility called e2defrag to defragment
  extended-2 filesystems. The current version does not work reliable
  enough to use it even for private environments. If you really want to
  defragment your filesystem, make a backup copy (better: two copies),
  practice restoring the data, then create a new filesystem (that will
  destroy the old) and restore the data. This sketch is currently the
  safest technique.

  4.3.  Is it possible to store the CD-image on an UMSDOS-filesystem?

  Yes. The only filesystem that isn't reliable and fast enough for
  writing CD-ROMs from is the network filesystem (NFS).  I used UMSDOS
  myself to share the disk-space between Linux and DOS/Win on a PC
  (486/66) dedicated for writing CD-ROMs.

  4.4.  Isn't there some way to get around the ISO-9660 limitations?

  Yes. You can put any filesystem you like on the CD. But other
  operating systems than Linux won't be able to deal with this CD.  Here
  goes the recipe:

  �  Create an empty file of 650MB size.

       dd if=/dev/zero of="empty_file" bs=1024k count=650

  �  Create an extended-2 filesystem on this file

       shell> /sbin/mke2fs  -b 2048  empty_file
       empty_file is not a block special device.
       Proceed anyway? (y,n) y

  �  Mount this empty file through the loopback devices (you need a
     reasonable new mount for this; read above).

       mount -t ext2 -o loop=/dev/loop1 empty_file /mnt

  �  Copy files to /mnt and umount it afterwards.

  �  Use cdrecord on empty_file (which is no longer empty) as if it were
     an ISO-9660-image.

  If you want to make an entry in /etc/fstab for such a CD, then disable
  the checking of the device file on system startup. For example:

       /dev/cdrom  /cdrom  ext2  defaults,ro  0 0

  The first 0 means "don't include in dumps" (backup), the second
  (=important) one means "don't check for errors on startup" (fsck would
  fail to check the CD for errors).

  4.5.  How to read the tracks from audio CDs?

  There are several software packages available. The newest one is
  "cdpranoia" and can be downloaded from


  Or you want to try the combination of "cdda2wav" and "sox", available
  from sunsite and its mirrors:



  cdda2wav enables you to get a specific interval (or a whole track)
  from your audio CD and converts it into a .wav-file.  sox converts the
  WAV files back into the (audio CD) cdda-format so it can be written to
  the CD-R using cdrecord. You don't necessarily need sox if you use a
  recent version of cdrecord, because it has built-in support for .au
  and .wav files.

  4.6.  How to probe for SCSI devices after boot?

  The file drivers/scsi/scsi.c contains the information

        * Usage: echo "scsi add-single-device 0 1 2 3" >/proc/scsi/scsi
        * with  "0 1 2 3" replaced by your "Host Channel Id Lun".
        * Consider this feature BETA.
        *     CAUTION: This is not for hot plugging your peripherals. As
        *     SCSI was not designed for this you could damage your
        *     hardware !
        * However perhaps it is legal to switch on an
        * already connected device. It is perhaps not
        * guaranteed this device doesn't corrupt an ongoing data transfer.

  Please note that this should only be used if your add SCSI devices to
  the end of the chain. Inserting new SCSI devices into an existing
  chain disturbs the naming of devices (directory /dev) and may destroy
  the complete content of your hard disk.

  Some kernel versions do not like re-scanning the SCSI bus at all and
  your system may freeze solid when trying out the above. You have been

  4.7.  Is it possible to make a 1:1 copy of a data CD?

  Yes. But you should be aware of the fact that any errors while reading
  the original (due to dust or scratches) will result in a defective
  copy.  Please note that both methods will fail on audio CDs! You have
  to use cdrdao or cdda2wav on audio CDs.

  First case: you have a CD-writer and a separate CD-ROM drive. By
  issuing the command

  cdrecord -v dev=0,6,0 speed=2 -isosize /dev/scd0

  you read the data stream from the CD-ROM drive attached as /dev/scd0
  and write it directly to the CD-writer.

  Second case: you don't have a separate CD-ROM drive. In this case you
  have to use the CD-writer to read out the CD-ROM first:

       dd if=/dev/scd0 of=cdimage

  This command reads the content of the CD-ROM from the device /dev/scd0
  and writes it into the file "cdimage". The contents of this file are
  equivalent to what mkisofs produces, so you can proceed as described
  earlier in this document (which is to take the file cdimage as input
  for cdrecord).  If you want to see a progress-meter and other fancy
  stuff, then you can also use J�rg Schillings  sdd.

  In case you run into errors, then install a recent version of
  cdrecord, which ships a tool called "readcd" (found under misc/). It
  gives you the same result as dd, but reads sectors on the CD-ROM
  several times in case of errors.

  4.8.  Can Linux read Joliet CD-ROMs? (obsolete answer)

  Yes. Newer Kernels (2.0.36 and the upcoming 2.2) have built-in support
  for the joliet format. Remember you have to use both options in your
  /etc/fstab: the keywords iso9660 and joliet (later is really an
  extension).  For more details, see  <http://www->.

  4.9.  How do I read/mount CD-ROMs with the CD-writer?

  Just as you do with regular CD-ROM drives. No tricks at all. Note that
  you have to use the scd devices (SCSI CD-ROM) to mount CD-ROMs for
  reading, even if you have an ATAPI CD-ROM (remember you configured
  your ATAPI devices to act like SCSI). Example entry for /etc/fstab:

       /dev/scd0  /cdrom  iso9660  ro,user,noauto  0  0

  4.10.  How to put even more data on the CD-R?

  Use bzip2 instead of any other compressor like gzip or pkzip. It will
  save you up to 30% of disk-space for larger (>100kb) files. You can
  download it from


  Instead of writing a true audio CD, you can optionally convert your
  WAV audio files into MP3 audio files and store them on a ISO-9660
  filesystem as regular files. Usually MPEG III give you a compression
  of 1:10. Of course, most CD-players are not able to read files... this
  is the drawback. On the other hand, why not running the music for your
  next party from hard disk? 18 Gbytes are enough for 3000-4000 titles.

  A software MPEG III-encoder is available from


  A MPEG III-player is available from


  For recorded speech, you may want to try to reduce its size using
  shorten or "GSM lossy speech compression":



  4.11.  How to make bootable CD-ROMs?

  You must have an 1.44 MB bootable floppy-disk. Create an exact image
  of this floppy-disk by issuing the command

       dd if=/dev/fd0 of=boot.img bs=18k

  Place this floppy image into the directory holding the collection of
  your files (or into a subdirectory of it, just as you like). Tell
  mkisofs about this file with the option '-b' and also use '-c'. For
  details read the file README.eltorito in the mkisofs-distribution.

  An interesting application for a custom bootable CD is as a virus safe
  DOS- or Windows-system. It saves you the money for the hard disks (if
  you have a network and use samba to put the user-data on a file
  server). The German computer magazine c't has a article about this
  issue in the issue 11/99, page 206 ( <>).

  Some details about the bootable RedHat CD-ROM is available from

  4.12.  How to make CD-ROMs writable like a hard disk?

  There is an overlay filesystem available for Linux, which is mounted
  over the CD-ROM and intercepts all writing operations. New and
  modified files are stored elsewhere, but for the user it looks like
  the CD-ROM is modified. For more information, see

  If that is not enough for your needs: wait for the UDF-filesystem to
  be supported by Linux or help developing it (see
  <>. At the moment only reading of CD-
  media is supported due to a limitation in the CD-ROM drivers of the
  Linux kernel.

  4.13.  Is it possible to use several writers at once?

  Yes. It is reported to work with at least 3 writers at full speed (6x)
  on a PC with 233 Mhz and a single SCSI bus running kernel 2.2.12. You
  need either a recent version of the Linux kernel (2.2.12 or higher).

  4.14.  What about Solaris, *BSD, AIX, HP-UX, etc.? Is my variant of
  Unix supported?

  Only chapter 2 is Linux-specific. You can apply chapter 3 and 4 even
  if you run another family of operating systems than Linux. Please see
  the files README.NetBSD, README.aix, README.hpux,,
  README.solaris, README.sunos, README.vms or README.xxxBSD from the

  Probably yes. Compile cdrecord for your platform and issue the command
  "cdrecord -scanbus". Read the README.* file for your Unix distributed
  with the sources of cdrecord. However, not all variants of Unix can
  read the RockRidge, Joliet or HFS extensions on your newly written CD-

  4.15.  Where to store the local configuration permanently?

  You have two options. Either you use the built-in configuration file
  for cdrecord, or you use a shell wrapper like the one shown below.
  This shell script reads a configuration file, which lists the options
  and parameters for cdrecord line by line. The names are exactly the
  same as on the command line, but without the leading dash. Comments
  are allowed.  Example:

       # be verbose
       # set the speed of the writer
       # the device-coordinates in the form BUS,ID,LUN

  The configuration files for the wrapper belong into /etc/cdrecord/ and
  must be referenced on the command line. Example: if you want to refer
  to the configuration /etc/cdrecord/mywriter.cfg, then you can issue
  the command " mywriter.cfg -audio track1...".  Everything
  after mywrite.cfg is passed to cdrecord.

       #! /bin/bash



       if [ ! -f "$CFGDIR/$CFG" ]
           echo "Configuration file $CFGDIR/$CFG not found. Exiting."
           exit 1

       while read LINE
           case $LINE in
               \#*|"") continue;;
           set -- $LINE
           while shift
               case $1 in
                   "") continue;;

           if [ -z "$O_VALUE" ]
               O_CDRECORD="$O_CDRECORD -$O_NAME "

       done < "$CFGDIR/$CFG"

       set -x    #DEBUG
       exec cdrecord $O_CDRECORD $ARGS_LEFT
       echo "Execution of cdrecord failed."

  4.16.  How can the CD-info be retrieved?

  Somewhere behind the first 32 k on the CD, a block with information
  about the CD is located. You can extract the information with the
  following shell script:

  #! /bin/bash

  for i in 32768,7   32776,32 32808,32 32958,128 33086,128 33214,128 \
           33342,128 33470,32 33581,16 33598,16  33615,16  33632,16
      set -- $i
      echo "*`dd if=$RD bs=1 skip=$OFFSET count=$LENGTH   2> /dev/null`#"

  4.17.  What about re-writing

  When overwriting  CD-RW media, specify the parameter blank=fast to
  cdrecord. That's all. See the man page of cdrecord for details about
  this parameter.

  4.18.  How to create a multi-session CD?

  First of all, the image for a multi-session CD must be formatted using
  the ISO-9660 filesystem using RockRidge-extensions. And you must use
  the option -multi for cdrecord as long as you want to add further
  sessions. So at least for the first session, you must specify the
  option -multi.

  Some CD-writers have no support for CD-ROM XA mode 2 or for session-
  at-once (SAO), so you need to specify the switch -data for cdrecord on
  the command line.

  The images for the second and subsequent sessions are a little bit
  more complicated to generate. Mkisofs must know where the free space
  on the CD-R begins. That information can be gathered by using the
  option -msinfo on cdrecord (see example below).

       shell> NEXT_TRACK=`cdrecord -msinfo dev=0,6,0`
       shell> echo $NEXT_TRACK
       shell> mkisofs -R -o cd_image2 -C $NEXT_TRACK -M /dev/scd5
                private_collection/ \

  For more information, please read the file README.multi, which is
  distributed with cdrecord.

  4.19.  Should I use the SCSI adapter shipped with the writer?

  Reported via email: Most CD-writer docs say to use a separate SCSI bus
  if going from a CD-ROM to a CD-writer and I have seen this myself in
  the following scenario:

  Adaptec 2940UW SCSI card, a 24x SCSI CD-ROM and a 4x4 SCSI CD-writer.
  When I got the CD-writer, it came with its own ISA SCSI card which
  could only handle one device.  I figured I'd toss this and use my
  better adaptec card for all the stuff. I noticed it was quite prone to
  buffer under-runs when recording at the 4x speed, but as soon as I
  tried hooking up the ISA SCSI card, it had no problems. I know 2 other
  people (both using adaptec 2940 cards), who have experienced exactely
  the same symptoms, usually when writing from a CD-ROM to a CD-
  recorder. Though I've never experienced the problem when going from a
  hard drive to a CD-writer on the same bus.

  4.20.  How to burn over the network?

  Usally a file transfer with FTP is fast enough to feed a CD-recorder
  at quadruple (4x) speed even over a 10 Mbit ethernet. You can couple
  the ftp-client and cdrecord via a fifo. First create a fifo named

       mkfifo cdimage
       get cdimg cdimage

  Then treat cdimage like a regular file, i.e. issue the following

       cdrecord dev=0,1,0 speed=2 cdimage

  Your ftp-client will notice when cdrecord wants to read from the file
  and will start transfering data from the ftp-host.

  4.21.  I hear a crack or click sound at the end of the each track.

  You have to use disk-at-once mode (DAO) to get rid of the cracks.

  4.22.  being root?  How can this be set up so that a user can burn CDs
  instead of always

  You can add the setuid-bit to the cdrecord-executable. However, this
  might be a security risk. Just setting the permissions on the device
  files does not help as cdrecord issues privileged commands via the
  SCSI generic interfaces.

       which cdrecord
       chown root.root /usr/bin/cdrecord
       chmod 4111 /usr/bin/cdrecord

  4.23.  Where do I get the "Yellow Book" and "Orange Book" standards?

  You get the printed specifications from Philips and they are

  4.24.  I've been searching for information on burning Video-CD under

  Here you can find utilities for creation of MPEG videos and Video-CDs:


  Political correct people mention the Berkeley-tools and other YUV-
  strategies. Their usage is complicated, takes much time and harddisk-
  space and gives you no audio track. I recommend to use conceptually
  higher level applications like the ones mentioned above.

  4.25.  Which is easier to set up, IDE or SCSI?

  SCSI CD-writers are slightly easier to set up with regard to CD-
  writing under Linux. And they are reported to have better error
  recovery. If that outweights the higher price cannot be answered

  4.26.  How can I overburn a CD using {cdrecord,cdrdao}?

  Overburning a CD-R is nothing special. It is at your own risk that the
  data fits on the CD-ROM, but thats all. There are no 650 Mbytes-limits
  in the software under Linux.

  4.27.  What will cdrecord do when it stops getting input from the

  It will finish writing. So you can just couple your favourite backup
  tool with cdrecord using a pipe, like in "bru -size=640m -f - |
  cdrecord dev=0,1,0 speed=2 -". You have to take special care within
  the backup utility if the backup spans multiple CD-Rs.

  4.28.  Is there an equivalent to ignore=hdX for the ide-scsi emula�

  I know of no way, but anybody is welcome to add this feature to the
  Linux kernel sources.

  4.29.  How many times can you re-use CD-RW before they become faulty?

  Good question.

  4.30.  Which format to choose for a platform independant CD-ROM?

  A CD-ROM to be read by all systems can only use the plain ISO 9660
  format. That means stupid 8+3 filenames from old MS-DOS and without
  any HFS (Macintosh), Joliet (Microsoft) or RockRidge (newer Unices)
  extensions.  There is no extension for longer filenames, which could
  be read by all operating systems.

  4.31.  Is multi-session for audio tracks possible?

  Audio CD-players are only able to deal with audio tracks stored in the
  first session. In other words, you cannot add audio tracks using
  subsequent sessions. However, writing data tracks into the second
  session effectively hides them from audio CD-players. This way you
  prevent having an silent track on your mixed mode CD (audio and data

  4.32.  What hardware resources do I need? Is an old Pentium enough?

  An answer depends on your wishes. If you need a reason to buy a new
  computer, here is the answer from the international association of
  computer manufactures: Whatever you plan to do, you need a processor
  with 800 Mhz. Because it won't fit into your existing motherboard, you
  need a new motherboard, too. The easiest solution is just to buy the
  typical complete offer as seen in advertisements on TV. Please ignore
  the rest of this section.

  Now the case if you just want a rational answer: I wrote several CD-
  ROMs sucessfully using a "486" with 66 Mhz. Although MS does not
  consider them to be PCs anymore, but recommends to run a CE version on
  them (seen on the CeBIT), Linux runs even fine on the predecessors of
  the Pentium and is even able to write CDs. You can easily find out if
  the power of your hardware is sufficient for writing CD-ROMs by
  testing it out. Just add the command line switch -dummy when executing
  cdrecord and the laser will be kept off. Watch the burning process.

  5.  Troubleshooting

  Always remember, that you can still use corrupt CD-ROMs as coasters.

  5.1.  It doesn't work: under Linux

  Please check first, that the writer works under the software it is
  shipped with (=under another operating system). Concretely:

  �  Does the controller recognize the writer as a SCSI device?

  �  Does the driver software recognize the writer?

  �  Is it possible to make a CD using the accompanied software?

  If "it doesn't even work" with the accompanied software you have a
  hardware conflict or defective hardware. If it works and you use
  loadlin to boot Linux, then that is a problem with loadlin. Loadlin
  makes a warm-boot with most of the hardware already initialized and
  that can confuse the Linux kernel.

  5.2.  Error-message: No read access for 'dev=0,6,0'.

  Under Linux, some versions of the C-library are incompatible (buggy),
  so that an application linked against one version will not work with
  another. An example for an error triggered by pre-compiled binaries is
  the following:

       [root@Blue /dev]# cdrecord -eject dev=0,6,0
       cdrecord: No such file or directory. No read access for 'dev=0,6,0'.

  The solution is to install a newer C-library.

  5.3.  It doesn't work: under DOS and friends

  Try to use Linux. Installation and configuration of SCSI drivers for
  DOS is the hell. Linux is too complicated? Ha!

  5.4.  SCSI errors during the burning phase

  Most likely those errors are caused by

  �  missing dis-/reconnect feature on the SCSI bus

  �  insufficiently cooled hardware

  �  defective hardware (should be detected by 5.1.)

  Under various circumstances SCSI devices dis- and reconnect themselves
  (electronically) from the SCSI bus. If this feature is not available
  (check controller and kernel parameters) some writers run into trouble
  during burning or fixating the CD-R.

  Especially the NCR 53c7,8xx SCSI driver has the feature disabled by
  default, so you might want to check it first:

       NCR53c7,8xx SCSI support                  [N/y/m/?] y
          always negotiate synchronous transfers [N/y/?] (NEW) n
          allow FAST-SCSI [10MHz]                [N/y/?] (NEW) y
          allow DISCONNECT                       [N/y/?] (NEW) y

  5.5.  If cdrecord reports medium errors in the form of "Sense Key: ...
  Medium Error, Segment ...", then the medium is not empty. If you use
  CD-RW, then try to switch from blank=fast to the more reliable
  blank=all. If you use CD-R only, then make sure the CD-R has never
  seen a CD-writer before or try out discs from another manufacturer.
  Medium errors

  5.6.  Newly written CDs are not readable on some players.

  Some people reported problems with playing their self-written CDs.
  Very old audio players or car devices can have problems with CD-Rs,
  although this is extremly rare. Quite frequent are problems with CD-
  RWs, because they don't reflect the laserlight as good as CD-Rs and
  factory-pressed "silver" discs.

  5.7.  My scanner stopped working after I loaded the ide-scsi module

  By inserting the SCSI-hostadaptor emulation, the naming of SCSI
  devices changes. If your scanner was /dev/sg0 before, it might be
  /dev/sg1 or /dev/sg2 now. Prominent kernel developers did not think
  this is completely braindead and denied solutions like devfs in the
  past. But that is another story, the first thing you should try is to
  set the link /dev/scanner to point to the actual generic SCSI device.

       cd /dev
       ls -l scanner     # shows current setting
       ln -sf sg2 scanner
       # test the scanner
       ln -sf sg1 scanner
       # test the scanner
       # and so on

  Application developers should carefully think about support for this
  dangerous and error prone naming scheme. Please consider at least to
  use intermediate solutions like the SCSI coordinates used by cdrecord.

  6.  Credits

  Many thanks go to the readers of this HOWTO, who contributed actively
  to its contents. As I don't had access to a CD-writer myself for
  several years, reports about real live setups and experience have
  always been of great value to me.

     Doug Alcorn <>
        helped to improve the handling of newer kernels

     Kalle Andersson <>
        How to write audio CDs directly from MP3.

     Alan Brown <>

     Rick Cochran <>
        hint about dis-/reconnect disabled by default in the ncr driver

     Robert Doolittle <>
        good arguments for dropping cdwrite from the HOWTO
     Markus Dickebohm <>

     Thomas Duffy <>
        major cleanup of syntax and spelling

     Dave Forrest  <>
        fixed adapter spelling problems

     Jos van Geffen <>
        noted the problem in 4.9.

     Bernhard Gubanka <>
        noticed the need of a recent version of mount to utilize the
        loopback device

     Stephen Harris <>
        contributed hint about writing audio CDs

     Janne Himanka <>
        pointer to kernel patch to read Joliet CD-ROMs

     Stephan Noy <>
        information and experience about writing audio CDs

     Don H. Olive <>
        URL of the mkhybrid tool

     Jesper Pedersen <>

     Pierre Pfister <>
        helped to develop the recipe on 1:1 copies.

     Daniel A. Quist <>
        information about IDE CD-R and newer kernel versions
        Reported problem with pre-initialized writers when booting via

     Dale Scheetz <>

     Joerg Schilling <>
        many informations about cdrecord

     Martin Schulze <joey@Infodrom.North.DE>
        gave information about the cdwrite-mailinglist

     Gerald C Snyder <>
        tested writing of an ext2 CD-ROM (see 4.4)

     Art Stone <>
        had the idea to put non-ISO-9660 filesystems on a CD
     The Sheepy One <>
        suggested using defective CD-ROMs as coasters for drinks

     Erwin Zoer <>

  Futhermore, I would like to thank the following people for reporting
  spelling mistakes: Bartosz Maruszewski
  <>, Alessandro Rubini <>,
  Ian Stirling <>, Brian H. Toby.

  End of the Linux CD-Writing HOWTO. (You can stop reading here.)

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