Install for K12LTSP

Fl_TeacherTool should be installed by default with K12LTSP. To update to the latest version simply type

# yum install fl_teachertool

Enable Monitor/Control

  1. Edit the file /opt/ltsp/i386/etc/lts.conf and uncomment (i.e. remove the "#"): X4_MODULE_02 = vnc
  2. Become root: su -
  3. Make a password for the vnc-session: /usr/bin/vncpasswd
  4. Copy the password file into the ltsp-tree: cp -a /root/.vnc /opt/ltsp/i386/root/
  5. Log out of root session: exit
  6. Reboot your clients!
****Security Notice as of Oct 27, 2008:
Enabling Monitor/Control is no longer recommended.

A security vulnerability exists if you enabled Monitor/Control 
by following the instructions above:

Please be aware that anyone with some Linux knowledge could
potentially take control of, or monitor, a client computer.

If you do not feel comfortable with this situation, 
especially if the teacher workstation is a client machine,
then follow the simple work around patch below.

******Work Around / Patch:******
Notice: this will disable monitor/control and snapshots in
Fl_Teachertool.

Edit the file /opt/ltsp/i386/etc/lts.conf and *COMMENT*
the vnc module line 
(i.e. INSERT a "#" at the beginning of the line): 

# X4_MODULE_02 = vnc

reboot the client machines.

For good measure, delete your old vnc password files:
rm  /opt/ltsp/i386/root/.vnc/passwd
rm  /root/.vnc/passwd

Allow Non-Root Users to Run Fl_TeacherTool

This enables teachers who do not have root password to run fl_teachertool.

  1. Create a new group called "teachers" using system-config-users
    You can run this from GNOME using System, Administration, Users and Groups.
  2. Add the "teachers" group to each user who needs to run fl_teachertool.
  3. Become root with $su -
  4. Run: visudo This is a special editor for the sudoers file.
  5. Add the following line to the end of the file using vi editing techniques: %teachers ALL=NOPASSWD:/usr/sbin/fl_teachertool
    Enter at least one blank line at the end of the file. If you don't know vi then just goto the last line and hit the letter "i" for (insert) then type the above line, hit enter, then hit the escape key. Now type
    :wq and hit <enter>. This saves and exits. Alternatively, you can set the EDITOR environment variable to a different text editor. nano is a friendly editor:
    export EDITOR=/usr/bin/nano; visudo
  6. If your fellow teachers are not comfortable typing "sudo /usr/sbin/fl_teachertool" then add an alias in file .bashrc (notice it starts with a period) in the home directory of the people who will run the program.
    # User specific aliases and functions
    alias teach='sudo /usr/sbin/fl_teachertool'
    Then they only have to type teach or alternatively put a launcher icon with the command sudo /usr/sbin/fl_teachertool on their desktop.