[K12OSN] Re: teachertool upgrade

Robert Arkiletian robark at gmail.com
Thu Nov 13 19:17:29 UTC 2008

On Wed, Nov 12, 2008 at 9:38 PM, John Montoya <jomontoya at kern.org> wrote:
> Hello,
> I need help with a new k12LTSP 5 EL server install.
> I would like to update the existing 4.2 installed and running version of fl_teachertool.
> I want to use the newest version of teachertool - v0.62
> The install documents are a little confusing.

Okay I will walk you through it.

yum  install  fltk  fltk-devel
yum  install  libXpm-devel  libpng-devel   libjpeg-devel
yum  install  libXmu-devel  libXaw-devel  imake
yum  install  xscreensaver-base
yum install vncreflector

wget  http://downloads.sourceforge.net/vnc-tight/tightvnc-1.3.9_unixsrc.tar.bz2

tar  -xvjf  tightvnc-1.3.9_unixsrc.tar.bz2
cd to the tightvnc dir
and type

make World

cp vncviewer binary to /usr/bin but rename it to teachertool-vncviewer
cp vncpasswd binary to /usr/bin but rename it to teachertool-vncpasswd

wget  http://downloads.sourceforge.net/vncsnapshot/vncsnapshot-1.2a-src.tar.gz

tar  -xvzf  vncsnapshot-1.2a-src.tar.gz
cd to the dir
then type


cp  vncsnapshot  /usr/bin

wget  http://www3.telus.net/public/robark/Fl_TeacherTool/fl_teachertool-0.62-src.tar.gz

tar -xvzf  fl_teachertool-0.62-src.tar.gz
cd to the dir
then type

make  install

The rest is exactly copied from my site:
(understand that there is a certain amount of risk to enabling
control/monitor) If you decide to enable this do not enable shell or
telnet in lts.conf
in /opt/ltsp/i386/etc/lts.conf

that is, keep these commented out

  #SCREEN_02          = shell
  #SCREEN_03          = telnet

 and also don't allow students to bring in laptops (with linux) There
is a risk that the monitor/control password can be stolen.

Next follow the old steps to enable monitor/control in k12ltsp


(Note: Oct 27, 2008 The procedure in the above link produces a security
issue and is no longer recommended. This means Control/Monitor/Snapshots will
not work. See link for further details.)

Almost finished...

Next (as root of course)

mkdir  -p  /usr/local/etc/fl_teachertool/teacher
chmod  700  /usr/local/etc/fl_teachertool/teacher

Now create a new file
vim  /usr/local/etc/fl_teachertool/teacher/vncreflectorpass

inside this file you should type two passwords like this


You make up your own passwords. They should be in plain text.
chmod 600  /usr/local/etc/fl_teachertool/teacher/vncreflectorpass

Now you need to create the encrypted versions of these plain text passwords
Again as root issue the command:

teachertool-vncpasswd  /usr/local/etc/fl_teachertool/teacher/teacherpass

Now only type in *one* password.
The one you typed in the first line of vncreflectorpass (eg fullcontrolpassword)
chmod 600  /usr/local/etc/fl_teachertool/teacher/teacherpass

teachertool-vncpasswd  /usr/local/etc/fl_teachertool/clientpass

Note: the dir is *not* the same as teacherpass
Again only type in *one* password.
The one you typed in the second line of vncreflectorpass (eg viewonlypassword)

chmod  644  /usr/local/etc/fl_teachertool/clientpass

Last thing:
Make your broadcast windows bigger than 800x600
I prefer 1024x768 broadcast windows

vim /etc/xinetd.d/vncts

change 16bit 800x600 to 1024x768

#service xinetd restart

That's it. Don't forget to configure
if you have multiple rooms (or wish to divide classrooms into sections)

If you are not sure how to configure it read the docs here
Specifically the last 2 sections.


> Any guidance will be appreciated,
> thanks,
> -john
> --
> This message was scanned by KCSOS and is believed to be clean.

Robert Arkiletian
Eric Hamber Secondary, Vancouver, Canada
Fl_TeacherTool http://www3.telus.net/public/robark/Fl_TeacherTool/
C++ GUI tutorial http://www3.telus.net/public/robark/

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