PREREQUISITES:
- Linux operating system ( I am using RedHat 6.2 );
- MRTG version ( I used 2.8.8 version );
- SHELL scripting language;
- PERL with Net::Telnet module (the last version of this module
you could find at http://search.cpan.org/search?module=Net::Telnet );
- AWK scripting language;
- TELNET client;
- CRON daemon installed;
- TCP/IP Network connection {:-)
INSTALLATION
This script was inspired from diskmon utility in contib section
of MRTG application. Basically it is working in the same way
with diskmon, but the diference (it has to be) is the following:
- it is not launched normally from your old MRTG, it is launched
separatelly by cron daemon
You need MRTG host machine and you could have any clients you want.
On the client machine (let say for example MailServer) you need to
configure in inetd.conf one more service, like this:
############################
# /etc/inetd.conf -rw-r--r--
#
mrtgrq stream tcp nowait root /usr/sbin/tcpd /usr/sbin/mrtgrq
#
# EOF
############################
The 'mrtgrq' is a script file which use the repquota utility
for partitioned disks using quotation mark.
I am using the following 'mrtgrq' script for reading each
qmail-user used space:
#!/bin/sh
/usr/sbin/repquota -vua | /bin/egrep -v '(\*|Block|User|root|bin|daemon|news|uucp|games|ftp|squid|named|postgres|gdm|nobody|xfs|alias|qmail|admin)' | sort -k1
exit 0
As you can see, I cut off from reports informations for other normal user
not involved in qmail transactions (see egrep).
Of course you need to declare in your services file the new tcp service
called mrtgrq, like this:
##########################
# /etc/services -rw-r--r--
#
mrtgrq 9000/tcp # MRTG Repquota service
#
# EOF
############################
You may use a different free port number you want, but you have
to keep in mind this, because you'll need it on MRTG machine.
For client everything is almost done, just kill -HUP the inetd
daemon. You may wish to test if everything it's fine on
the client side, for this just isue the following
command:
telnet <your.client.name_or_ip> 9000
You should see the result from the repquota utility.
The MRTG side is following:
mrtgrq
I use this script to monitor the disk-space used by e-mail users
on MailServer ( I am using Qmail ). Usage is very simple:
- Put in your crontab file a line which have to be run
every ten (10) minute or any other time interval you want
(but you have to edit, according with this new value,
'make-mrtg.cfg.awk' file). I am using Linux RedHat 6.2
and in my /etc/cron.d I put a file named 'net-hosts' with
the following structure:
##################################
# /etc/cron.d/net-hosts -rw-r--r--
#
*/10 * * * * root /usr/local/mrtg/contrib/mrtgrq/mrtgrq
#
# EOF
##################################
- Restart your cron daemon... and wait
To install, first edit the variables from both 'make-mrtg.cfg.awk'
and 'mrtgrq' files as needed. I found it easier to have these defined
rather than hardcoded due to differences between code interpretations.
You don't have to insert any other target in your own mrtg.cfg
file that you already have, because this script is launched by
the cron daemon.
make-mrtg.cfg.awk
This is the core of the entire task. Here I make 'mrtg-awk.cfg'
file using the output of 'getreport.pl' from a temporary
file 'mrtgrq-temp.tmp' which finally will be erased.
After doing this, internaly is lauched 'mrtg' executable
for mrtgrq's mrtg.cfg file (named 'mrtg-awk.cfg').
You could use 'indexmaker' script provided with MRTG
for doing an index.html file (see an example in 'mrtgrq').
Be aware ! You have to place icons (MRTG) and image files
(grnball.gif, redball.gif, cubprev.gif) in the same
location. You also have to place 'mrtgrq.css' into declared
location inside that AWK script file.
getreport.pl
This script in Perl requires Net::Telnet module instaled.
Its only task is to read the client on port 9000 (or other
you want) and print this output.
This output is redirected into a temporary file which
will be the input for the AWK script.
----------
Direct questions or suggestions to me.
Have fun!
-Adrian Turcu <adrianturcu@yahoo.com>