Provided by: live-boot-doc_3.0~a19-1_all bug


       live-boot - System Boot Scripts


       live-boot  contains  the  scripts  that  configure a Debian Live system
       during the boot process (early userspace).

       live-boot is a  hook  for  the  initramfs-tools,  used  to  generate  a
       initramfs  capable  to  boot  live  systems,  such  as those created by
       live-helper(7). This includes the Debian Live isos,  netboot  tarballs,
       and usb stick images.

       At  boot time it will look for a (read-only) media containing a "/live"
       directory where a root filesystems (often a compressed filesystem image
       like  squashfs)  is  stored.  If  found,  it  will  create  a  writable
       environment, using aufs, for Debian like systems to boot from.


       live-boot can be configured through a boot parameter or a configuration

   Kernel Parameters
       live-boot  is  only  activated  if  'boot=live'  was  used  as a kernel

       In addition, there are some  more  boot  parameters  to  influence  the
       behaviour, see below.

   Configuration Files
       live-boot  can  be configured (but not activated) through configuration
       files. Those files can be placed either in the root  filesystem  itself
       (/etc/live/boot.conf,   /etc/live/boot.d/),   or   on  the  live  media
       (live/boot.conf, live/boot.d/).


       live-boot currently features the following parameters.

           Set the accessibility level  for  physically  or  visually  impared
           users.  ACCESS  must  be  one  of  v1, v2, v3, m1, or m2. v1=lesser
           visual impairment,  v2=moderate  visual  impairment,  v3=blindness,
           m1=minor motor difficulties, m2=moderate motor difficulties.

           Set  the  default  console to be used with the "live-getty" option.
           Example: "console=ttyS0,115200"

           Makes initramfs boot process more verbose.
           Use: debug=1
           Without setting debug to a value the messages may not be shown.


           Another form of netboot by downloading  a  squashfs  image  from  a
           given url.  The fetch method copies the image to ram and the httpfs
           method uses fuse and httpfs2 to mount the image in  place.  Copying
           to  ram  requires  more memory and might take a long time for large
           images. However, it is more likely to  work  correctly  because  it
           does  not  require  networking  afterwards  and the system operates
           faster once booted because it  does  not  require  to  contact  the
           server anymore.
           Due  to current limitations in busyboxs wget and DNS resolution, an
           URL can not contain a hostname but an IP only.
           Not working:
           Also note that therefore it's currently not possible  to  fetch  an
           image from a namebased virtualhost of an httpd if it is sharing the
           ip with the main httpd instance.
           You may also use the live iso image in place of the squashfs image.

           Boot from an iSCSI target that has an iso or disk live image as one
           of its LUNs. The specified target is searched for a LUN which looks
           like a live media. If you use the iscsitarget software iSCSI target
           solution which is packaged in Debian your ietd.conf might look like
           # The target-name you specify in the iscsi= parameter
           Target <target-name>
             Lun 0 Path=<path-to-your-live-image.iso>,Type=fileio,IOMode=ro
             # If you want to boot multiple machines you might want to look at
           tuning some parameters like
             # Wthreads or MaxConnections

           Allows  to  use  a  filesystem  from  within  an  iso  image that's
           available on live-media.

           Do not check that any UUID embedded in the  initramfs  matches  the
           discovered  medium.  live-boot  may  be  told to generate a UUID by
           setting LIVE_GENERATE_UUID=1 when building the initramfs.

           If specified, an MD5 sum is calculated on  the  live  media  during
           boot  and  compared  to  the value found in md5sum.txt found in the
           root directory of the live media.

           Let you specify the name(s) and the  options  of  the  interface(s)
           that  should be configured at boot time. Do not specify this if you
           want to use dhcp (default). It will be changed in a future  release
           to   mimick   official   kernel   boot  param  specification  (e.g.

           If this variable is set, dhcp and  static  configuration  are  just
           skipped  and  the system will use the (must be) media-preconfigured
           /etc/network/interfaces instead.

           If you specify one of this two  equivalent  forms,  live-boot  will
           first  try  to find this device for the "/live" directory where the
           read-only root  filesystem  should  reside.  If  it  did  not  find
           something usable, the normal scan for block devices is performed.
           Instead of specifing an actual device name, the keyword 'removable'
           can be used to  limit  the  search  of  acceptable  live  media  to
           removable  type only. Note that if you want to further restrict the
           media to usb mass storage only, you  can  use  the  'removable-usb'

           live-boot   will  mount  the  encrypted  rootfs  TYPE,  asking  the
           passphrase,  useful  to  build  paranoid  live  systems  :-).  TYPE
           supported so far are "aes" for loop-aes encryption type.

           This  way you could tell live-boot that your image starts at offset
           BYTES in the above specified or autodiscovered device,  this  could
           be  useful  to hide the Debian Live iso or image inside another iso
           or image, to create "clean" images.

           Sets the path to the live filesystem on the medium. By default,  it
           is  set  to  '/live' and you should not change that unless you have
           customized your media accordingly.

           Set  the  timeout  in  seconds  for   the   device   specified   by
           "live-media=" to become ready before giving up.

           Instead of using the default optional file "filesystem.module" (see
           below) another  file  could  be  specified  without  the  extension
           ".module";  it  should  be  placed on "/live" directory of the live

           This tells live-boot to perform  a  network  mount.  The  parameter
           "nfsroot="  (with optional "nfsopts="), should specify where is the
           location of the root filesystem.   With  no  args,  will  try  cifs
           first, and if it fails nfs.

           This lets you specify custom nfs options.

           This  parameter disables the default disabling of filesystem checks
           in /etc/fstab. If you have static filesystems on your harddisk  and
           you  want  them  to  be  checked  at boot time, use this parameter,
           otherwise they are skipped.

           disables the "persistent" feature, useful if the  bootloader  (like
           syslinux) has been installed with persistent enabled.

           Do  not  prompt  to  eject  the CD or remove the USB flash drive on

           This  tells  live-boot  not  to  prompt  to  eject  the  CD   (when
           noprompt=cd)  or  remove the USB flash drive (when noprompt=usb) on

           This parameters allows to set a custom ramdisk size (it's  the  '-o
           size'  option of tmpfs mount). By default, there is no ramdisk size
           set, so the default of mount applies (currently  50%  of  available
           RAM). Note that this option has no currently no effect when booting
           with toram.

           This parameter enables usage of local swap partitions.

           live-boot will look for persistent and snapshot partitions or files
           labeled   "live-rw",   "home-rw",   and  files  called  "live-sn*",
           "home-sn*" and will try to, in order:  mount  as  /cow  the  first,
           mount the second in /home, and just copy the contents of the latter
           in appropriate locations (snapshots). Snapshots will be tried to be
           updated  on  reboot/shutdown.  Look  at  live-snapshot(1)  for more
           If "nofiles" is specified, only filesystems  with  matching  labels
           will  be  searched;  no  filesystems  will be traversed looking for
           archives or image files. This results in shorter boot times.
           If "cryptsetup" is specified, filesystems stored on  Luks-encrypted
           devices  will  be considered as well as others when searching for a
           persistence filesystem; the user will be prompted  for  any  needed
           decryption passphrase.

           live-boot  will look for persistency files in the root directory of
           a partition, with this parameter, the path  can  be  configured  so
           that  you  can  have  multiple directories on the same partition to
           store persistency files.

           Add a suffix when searching for the image  filenames  or  partition
           labels  to  use  for  the  above  mentioned persistent feature, the
           SUFFIX will be added after a dash (e.g.: "live-sn" would  transform
           to  "live-sn-SUFFIX").  This  is  handy  to test multiple live-boot
           based live-systems with different persistent storage choices.

           A path to a file present on the rootfs could  be  used  to  preseed
           debconf database.

           All  debian installed packages could be preseeded from command-line
           that way,  beware  of  blanks  spaces,  they  will  interfere  with
           parsing, use a preseed file in this case.

           This  option causes live-boot to reboot without attempting to eject
           the media and without asking the user to remove the boot media.

           This  parameter  will  make  live-boot  to  show  on  "/"  the   ro
           filesystems  (mostly compressed) on "/live". This is not enabled by
           default because could lead to problems by applications like  "mono"
           which store binary paths on installation.

           If  you  boot with the normal quiet parameter, live-boot hides most
           messages of its own. When adding silent, it hides all.

           Adding this parameter,  live-boot  will  try  to  copy  the  entire
           read-only  media  to  the specified device before mounting the root
           filesystem. It probably needs a lot of free space. Subsequent boots
           should then skip this step and just specify the "live-media=DEVICE"
           boot parameter with the same DEVICE used this time.

           Adding this  parameter,  live-boot  will  try  to  copy  the  whole
           read-only  media  to  the  computer's  RAM before mounting the root
           filesystem. This could need a lot of ram, according  to  the  space
           used by the read-only media.

           By  default,  live-boot  uses  aufs.  With  this parameter, you can
           switch to unionfs.

FILES (old)

           Some variables can be configured via this config file  (inside  the
           live system).

           This  optional  file  (inside  the  live  media) contains a list of
           white-space or carriage-return-separated file  names  corresponding
           to  disk images in the "/live" directory. If this file exists, only
           images listed here will be merged into the root aufs, and they will
           be  loaded  in  the order listed here. The first entry in this file
           will be the "lowest" point in the aufs, and the last file  in  this
           list  will  be  on  the  "top"  of  the  aufs, directly below /cow.
           Without this file, any images in the "/live" directory  are  loaded
           in alphanumeric order.

           This  optional file (which resides in the rootfs system, not in the
           live media) is used as a list of  directories  which  not  need  be
           persistent: ie. their content does not need to survive reboots when
           using the persistence features.
           This saves expensive writes and speeds up  operations  on  volatile
           data  such  as  web  caches and temporary files (like e.g. /tmp and
           .mozilla) which are regenerated each time. This is achieved by bind
           mounting each listed directory with a tmpfs on the original path.












       More  information  about  live-boot  and the Debian Live project can be
       found on the homepage at <> and in the manual at


       Bugs  can  be  reported  by  submitting  a  bugreport for the live-boot
       package in the Debian Bug Tracking System at  <>
       or  by  writing  a  mail  to  the  Debian Live mailing list at <debian->.


       live-boot was written by Daniel  Baumann  <>  for  the
       Debian project.