By doing a little bit of preparatory
work, we can make the numerous tasks involved with monitoring of the
children considerably simpler and also it would require less typing.
IP addresses are assigned on first come
first serve basis. So one day, if your oldest son signs on first, he
may get 192.168.0.2. On the next day, if he signs on late, he might
get 192.168.0.4. This makes it harder for you to determine which
computer is which. There are several things that can be done about
this.
- On most routers, there is a setting to assign a specific IP address to a computers MAC address or Host Name. If you enter:
ifconfig
The first line
displayed will have the word Hwaddr, followed by a series of numbers,
that will be your MAC address. But you will have to get the right
network interface. Eth0 is Ethernet, that is the one if you are
using a cable to connect the laptop to the router. More then likely,
it is going to be the paragraph starting with wlan0. That will be
the wireless network.
- If when you set up each laptop, you set the hostname to the child that was going to use the laptop. Upon ssh in the prompt would display something similar to:
parent@johnslaptop
That tells you
immediately whose computer you are on. Therefore, if you have
already checked that computer this week, sign off and move on to the
next one.
If you didn't set
that up, it's not too late. Sign in to John's Computer and just type
the following command:
sudo leafpad
/etc/hostname
And change whatever
name is there to johnslaptop and save the file.
If you are unsure
of whose computer you are signed on to, you can type “w” (on the
terminal program) and it will display any users signed on.
Let's start first with the desktop and
the ugly fping utility. So, log into your desktop and start a
terminal. We need to check that there is a “bin” directory and
that it is in your path. So, type in the following command:
ls -l | grep bin
If nothing is returned, we need to
create a bin directory. So type the following:
mkdir bin
Now to see if bin is in our path (case
is important):
echo $PATH
If you don't see bin in the output,
type
export PATH=$PATH:bin
Almost all Linux Distributions come
with a basic GUI editor. Gnome and Xfce usually come with gedit, KDE
usually comes with kate or kedit. Bohdi comes with leafpad, but you
can install gedit to keep things consistent. Whatever your system
came with, run that program. Now enter the following into the
editor:
#!/bin/bash
echo 'My IP
Address: '
ifconfig | grep 192
echo 'Network IP
Addresses'
/usr/sbin/fping -s
-g 192.168.0.0 192.168.0.255 -r 1 2> /dev/null | grep alive
Now save the file as “bin/myfping”
and then issue the following command
chmod +x bin/myfping
Now when you type in “myfping”,
your output will list your IP address first and then followed by all
of the “alive” IP Addresses on your network.
Now on each laptop, you will want to
create a bin directory on your user account. You will also want to
make sure the bin directory is in your path statement. Do all of
this as you did on the desktop.
In the E-mail step we determined what
the profile name was. We can put this in a script making easy and
quick starting of your childs E-mail Program. Note each laptop will
have a unique profile filename, therefore your script will also need
to be unique on each laptop. Using a text editor we will create a
email script as follows:
#!/bin/bash
thunderbird -offline -P “”
Then between the double quotes, put in
the Profile File Name. Save the file to something like bin/tbird and
then run a:
chmod +x bin/tbird
Which will give the script execution
rights. To run it, just type tbird.
Now we will do something similar for
sqliteman. Again the places.sqlite filename will be unique on each
laptop, so you will have to customize this script for each laptop.
#!/bin/bash
sqliteman
/home/charles/.mozilla/firefox/mwad0hks.default/places.sqlite
Then save the file to something like
bin/ffhistory and issue a chmod command to give it execution rights.
Eventully, your child will outgrow his
or her laptop. They will need to run programs that won't run on
these older computers. Make them make a case for it. If it is for
entertainment you can always say no. But if the need is real, you
can install the needed program on the desktop and then create a user
id on the the desktop for them. If it is a Windows application, most
will run under wine. And then from their laptop they can ssh into the
desktop and they can run the needed programs.
This will maximize your investment in
the desktop and their laptops will still be usable as dumb terminals.
Unusual behavior
You may notice one of your children
keeping long hours on his or her laptop and be defensive about what
they are doing. You can get an Approximate idea as to what they are
up to. One easy thing that you can do ssh into there laptop and run
the top command. This will show what programs are running. To make
it easier to look at, run it as follows “top -u ”
Where User ID is your child. This will just show the programs that
are owned by your child and not system processes. By looking at the
process names, you can determine if they are chatting, doing e-mail
or just on the web. If you want a longer term idea of what is going
on, you can set up a script like the following:
#!/bin/bash
echo `date` >> /home/parent/
CharlesLog.dat
ps -eo pcpu,pid,user,args | sort -k 1
-r | head -25 | grep >> /home/parent/
CharlesLog.dat
Replacing with your
Child's user ID.
The 2nd echo command even
though it goes 2 lines is actully just one line.
Note the quotes here are backward ticks
(to the left of the one on most keyboards).
Now save this to bin/cmonitor &
issue a “chmod + x” to it.
Now create a 2nd file and
give it any name you like
*/5 * * * * /home/parent/bin/cmonitor
Save the file and issue the following
command
crontab
With being the file
you just created. Now the script file bin/cmonitor will run every
five minutes adding the output to logfile. The Logfile will end up
looking something like the following:
Tue
Apr 17 13:28:47 EDT 2012
0.9
3752 charles gedit
0.9
3309 charles /opt/libreoffice3.4/program/soffice.bin --writer
0.3
2913 charles compiz --ignore-desktop-hints glib gconf gnomecompat
0.1
2761 charles /usr/libexec/multiload-applet-2
Each Program Run first writes the
Date/Time.
The Columnar data has the first column
being percent used, the 2nd has the program pid, the 3rd
is the user who owns the script/program and the last column is the
script. The next day, you should ssh back into this computer and
enter the following command:
crontab -r
That will stop the script from running
every 5 minutes. If you don't do this eventually the child would run
out of disk space.
No comments:
Post a Comment