Provided by: ltsp_22.01-2_all bug


       ltsp.conf - client configuration file for LTSP


       The LTSP client configuration file is placed at /etc/ltsp/ltsp.conf and it loosely follows
       the .ini format. It is able to control various settings of the LTSP  server  and  clients.
       After  each  ltsp.conf  modification, the ltsp initrd command needs to be run so that it's
       included in the additional ltsp.img initrd that is sent when the clients boot.


       To create an initial ltsp.conf, run the following command:

              install -m 0660 -g sudo /usr/share/ltsp/common/ltsp/ltsp.conf /etc/ltsp/ltsp.conf

       The optional -g sudo parameter allows users in the sudo group to edit ltsp.conf  with  any
       editor (e.g. gedit) without running sudo.


       Open  and  view the /etc/ltsp/ltsp.conf file that you just created, so that it's easier to
       understand its syntax.

       The configuration file is separated into sections:

              • The special [server] section is evaluated only by the ltsp server.

              • The special [common] section is evaluated by both the server and ltsp clients.

              • In the special [clients] section, parameters for  all  clients  can  be  defined.
                Most ltsp.conf parameters should be placed there.

              • MAC  address,  IP  address, or hostname sections can be used to apply settings to
                specific clients. Those support globs, for example [192.168.67.*].

              • It's also possible to group parameters into named sections like [crt_monitor]  in
                the example, and reference them from other sections with the INCLUDE= parameter.

              • Advanced  users  may  also  use  [applet/host]  sections,  for  example  [initrd-
                bottom/library*] would be evaluated by the ltsp  initrd-bottom  applet  only  for
                clients that have a hostname that starts with "library".

       The ltsp.conf configuration file is internally transformed into a shell script, so all the
       shell syntax rules apply, except for the  sections  headers  which  are  transformed  into

       This  means  that  you  must  not  use  spaces around the "=" sign, and that you may write
       comments using the "#" character.

       The ltsp initrd command does a quick syntax check by running sh -n /etc/ltsp/ltsp.conf and
       aborts if it detects syntax errors.


       The following parameters are currently defined; an example is given in each case.


              Add  or  omit  items  to the ltsp image exclusion list.  Some files and directories
              shouldn't be included in the generated image.   The  initial  list  is  defined  in
              /usr/share/ltsp/server/image/image.excludes.   It  can  be completely overridden by
              creating /etc/ltsp/image.excludes.  ADD_IMAGE_EXCLUDES and OMIT_IMAGE_EXCLUDES  can
              finetune  the  list by adding or removing lines to it. They can either be filenames
              or multiline text.





              Configure the display manager to log in this user automatically.  If SSHFS is used,
              the  PASSWORDS_x  parameter  (see below) must also be provided.  AUTOLOGIN can be a
              simple username like "user01", or it can  be  a  partial  regular  expression  that
              transforms  a  hostname  to  a  username.   For example, AUTOLOGIN="pc/guest" means
              "automatically log in as guest01  in  pc01,  as  guest02  in  pc02  etc".   Setting
              RELOGIN=0  will  make AUTOLOGIN work only once.  Finally, the *_CONF parameters can
              be either filenames or direct text, and provide a way to write  additional  content
              to the generated display manager configuration.

       CRONTAB_x="30 15   * * *   root    poweroff"
              Add a line in crontab. The example powers off the clients at 15:30.

              Set  the  CUPS  server  in  the  client /etc/cups/client.conf. Defaults to $SERVER.
              You're supposed to also enable printer sharing on the  server  by  running  cupsctl
              _share_printers=1  or  system-config-printer  or  by visiting http://localhost:631.
              Then all printers can be managed on the LTSP server.   Other  possible  values  are
              CUPS_SERVER="localhost",   when   a   printer   is   connected   to  a  client,  or
              CUPS_SERVER="ignore", to skip CUPS server handling.

              Write warnings and error messages to /run/ltsp/debug.log. Defaults to 0.

              Launch a debug shell when errors are detected. Defaults to 0.


       KERNEL_PARAMETERS="nomodeset noapic"

              These parameters can be defined under [mac:address] sections in ltsp.conf, and they
              are  used  by  ltsp  ipxe to generate the iPXE menu.  They control the default menu
              item, the additional kernel parameters and the menu timeout for each  client.  They
              can also be defined globally under [server].

       DISABLE_SESSION_SERVICES="evolution-addressbook-factory obex"

       DISABLE_SYSTEM_SERVICES="anydesk teamviewerd"


       KEEP_SYSTEM_SERVICES="apparmor ssh"

       MASK_SESSION_SERVICES="gnome-software-service update-notifier"

       MASK_SYSTEM_SERVICES="apt-daily apt-daily-upgrade rsyslog"
              Space separated lists of services to disable, permit or mask on LTSP clients.  They
              mostly correspond to systemctl disable/mask [--user]  invocations.   Setting  these
              ltsp.conf parameters adds or omits items from the default lists that are defined in
              /usr/share/ltsp/client/init/  Disabled services can  be  started  on
              demand by e.g. dbus or socket activation, while masked services need to be manually
              unmasked first.  Currently, MASK_SESSION_SERVICES also deletes the non-systemd user
              services from /etc/xdg/autostart.

              Specify the DNS servers for the clients.

       FSTAB_x="server:/home /home nfs defaults,nolock 0 0"
              All  parameters that start with FSTAB_ are sorted and then their values are written
              to /etc/fstab at the client init phase.

              Specify the client hostname. Defaults to "ltsp%{IP}".   HOSTNAME  may  contain  the
              %{IP}  pseudovariable, which is a sequence number calculated from the client IP and
              the subnet mask, or the %{MAC} pseudovariable, which is the MAC address without the

       HOSTS_x=" nfs-server"
              All  parameters that start with HOSTS_ are sorted and then their values are written
              to /etc/hosts at the client init phase.

              Specifying this option under the [clients] section copies the rootfs image  to  RAM
              during  boot.  That  makes clients less dependent on the server, but they must have
              sufficient memory to fit the image.

              Include another section in this section.

              Activate local swap partitions. Defaults to 1.


              MULTISEAT=1 tries to autodetect if an LTSP client has two  graphics  cards  and  to
              automatically  split  them along with the USB ports into two seats.  Optional lines
              like UDEV_SEAT_1_SOUND="*/sound/card1*" can be used to finetune the udev rules that
              will be generated and placed in a file named /etc/udev/rules.d/72-ltsp-seats.rules.

              Only  use  this  under  the  [server] section. Normally, ltsp service runs when the
              server boots and detects  if  a  server  IP  is,  in  which  case  it
              automatically  enables  IP  forwarding  for  the  clients  to be able to access the
              Internet in dual NIC setups. But if there's a chance that  the  IP  isn't  set  yet
              (e.g. disconnected network cable), setting NAT=1 enforces that.

       OMIT_FUNCTIONS="pam_main mask_services_main"
              A  space  separated  list  of function names that should be omitted.  The functions
              specified here will not be executed when called.  This option can be  specified  in
              any [section].

       PASSWORDS_x="teacher/cXdlcjEyMzQK [a-z][-0-9]*/MTIzNAo= guest[^:]*/"
              A  space  separated  list  of regular expressions that match usernames, followed by
              slash and base64-encoded passwords. At boot, ltsp init writes those  passwords  for
              the matching users in /etc/shadow, so that then pamltsp can pass them to SSH/SSHFS.
              The end result is that those users are able to login either in the console  or  the
              display manager by just pressing [Enter] at the password prompt.
              Passwords  are  base64-encoded to prevent over-the-shoulder spying and to avoid the
              need for escaping special characters. To encode a password in base64,  run  base64,
              type a single password, and then Ctrl+D.
              In  the example above, the teacher account will automatically use "qwer1234" as the
              password, the a1-01, b1-02 etc students  will  use  "1234",  and  the  guest01  etc
              accounts  will be able to use an empty password without even authenticating against
              the server; in this case, SSHFS can't be used, /home should be local or NFS.

       POST_APPLET_x="ln -s /etc/ltsp/xorg.conf /etc/X11/xorg.conf"
              All parameters that start with POST_ and then have an ltsp client applet  name  are
              sorted  and  their  values are executed after the main function of that applet. See
              the ltsp(8) man page for the available applets.  The  usual  place  to  run  client
              initialization commands that don't need to daemonize is POST_INIT_x.

              All  parameters  that  start with PRE_ and then have an ltsp client applet name are
              sorted and their values are executed before the main function of that applet.

              Normally, all the server users are listed on  the  client  login  screens  and  are
              permitted  to  log in. To exclude some of them, define one or more of those regular
              expressions. For more information, read  /usr/share/ltsp/client/login/pwmerge.  For
              example, if you name your clients pc01, pc02 etc, and your users a01, a02, b01, b02
              etc, then the following line only shows/allows  a01  and  b01  to  login  to  pc01:

       REMOTEAPPS="users-admin mate-about-me"
              Register  the specified applications as remoteapps, so that they're executed on the
              LTSP server via ssh -X instead of on the clients. For more information,  see  ltsp-

              Select   this   LTSP   image  to  boot  Raspberry  Pis  from.   This  symlinks  all
              $BASE_DIR/$RPI_IMAGE/boot/*  files  directly  under  $TFTP_DIR  when  ltsp   kernel
              $RPI_IMAGE   is   called.    See   the   Raspberry   Pi   OS   documentation   page
              ⟨⟩ for more information.

              A search domain to add to resolv.conf and to /etc/hosts. Usually provided by DHCP.

              The LTSP server is usually autodetected; it can be manually  specified  if  there's
              need for it.



       X_MODELINE='"1024x768_85.00"   94.50  1024 1096 1200 1376  768 771 775 809 -hsync +vsync'

       X_MODES='"1024x768" "800x600" "640x480"'



       X_VIRTUAL="800 600"
              If  any  of  these  parameters  are  set, the /usr/share/ltsp/client/init/xorg.conf
              template is installed to /etc/X11/xorg.conf, while applying the  parameters.   Read
              that  template  and  consult  xorg.conf(5)  for  more information.  The most widely
              supported method to set a default resolution is X_MODES.  If  more  parameters  are
              required, create a custom xorg.conf as described in the EXAMPLES section.


       To specify a hostname and a user to autologin in a client:


       The password above is "pass01" in base64 encoding. To calculate it, the base64 command was
       run in a terminal:

              <press Ctrl+D at this point>

       If some clients  need  a  custom  xorg.conf  file,  create  it  in  e.g.   /etc/ltsp/xorg-
       nvidia.conf,  and  put  the  following  in  ltsp.conf  to dynamically symlink it for those
       clients at boot:


              POST_INIT_LN_XORG="ln -sf ../ltsp/xorg-nvidia.conf /etc/X11/xorg.conf"

       Since ltsp.conf is transformed into a shell  script  and  sections  into  functions,  it's
       possible to directly include code or to call sections at POST_APPLET_x hooks.

              # Allow local root logins by setting a password hash for the root user.
              # The hash contains $, making it hard to escape in POST_INIT_x="sed ...".
              # So put sed in a section and call it at POST_INIT like this:

              # This is the hash of "qwer1234"; cat /etc/shadow to see your hash.
              sed 's|^root:[^:]*:|root:$6$VRfFL349App5$BfxBbLE.tYInJfeqyGTv2lbk6KOza3L2AMpQz7bMuCdb3ZsJacl9Nra7F/Zm7WZJbnK5kvK74Ik9WO2qGietM0:|' -i /etc/shadow


       Copyright 2019-2022 the LTSP team, see AUTHORS.


       ltsp(8), ltsp-dnsmasq(8), ltsp-image(8), ltsp-info(8), ltsp-initrd(8), ltsp-ipxe(8), ltsp-
       kernel(8), ltsp-nfs(8), ltsp-remoteapps(8)

       Online documentation is available on