SNMP-Monitor - README

SNMP::Monitor - A module for watching interface status, logging

                interface utilization and arbitrary other SNMP
                queries

1.) What is it?

Are you managing a network? Then you definitely want to be notified about status changes of your WAN lines. You are interested in displaying the utilization of both LAN and WAN. You'd like to have accounting statistics of your Internet connection. Or you want to have a comfortable possibility of watching other SNMP variables.

If HP OpenView or a similar program does this for you, stop reading here: You have something far better. If not, read on ...

The SNMP::Monitor package and its frontend 'snmpmon' allow you to

add or delete routers from or to a set of managed routers
start a permanently running monitor that is watching your interfaces and can do logging into a database
display a graphical view of the interface utilization via the WWW
show interface statistics
includes an access control system that restricts these information to given users based on interface and/or host

The main differences between SNMP::Monitor and packages like MRTG are:

SNMP::Monitor is a general purpose framework; you can easily add arbitrary SNMP variables and related triggers
A database engine is used for logging; thus SNMP::Monitor can easily give any kind of accounting report that you like.

If you'd like to see a running example, visit

http://www.zvw.de/snmpmon_public

2.) Prerequisites

Lots of. :-) First of all, some external binaries are required:

GNUplot 3.6beta or later is used for creating GIF images; if you don't have GNUplot, you can still use the SNMP monitor, but no graphical view is available. See

ftp://cmpc1.phys.soton.ac.uk/pub/

http://science.nas.nasa.gov/~woo/gnuplot/beta

The ppmtogif program, available as part of the netpbm package or as part of the libgr distribution. Sorry, I have no information for obtaining one of these packages available right now, except that libgr is part of my Red Hat Linux distribution. :-)
The SNMP client libraries from the UCD snmp distribution, see

ftp://ftp.ece.ucdavis.edu:/pub/snmp

      Note, that you don't need a running server, the libraries
      and header files are completely sufficient.

      Perhaps the CMU package or Juergen Schoenwaelder's version
      will do, I did not try. In this case you might need an
      older version of the SNMP module too, see below.

MySQL or another database engine with a DBI (Database independent interface for Perl 5) driver
Some other Perl modules:

          Data-Dumper, version 2.081 or later
          SNMP, version 1.8a1 or later
          MailTools, version 1.11 or later
          IO-stringy, version 1.203 or later
          HTML::EP, version 0.1005 or later
          Msql-Mysql-modules, 1.1832 or later (or perhaps your
              database engines driver)

      Missing Perl modules are available from

           ftp://ftp.funet.fi/pub/languages/perl/CPAN/modules/by-module

      See Installation below for how to install a Perl module

3.) Installation

First you install the Perl modules. For example the Data::Dumper module is installed as follows:

gzip -cd Data-Dumper-2.081.tar.gz | tar xf - cd Data-Dumper-2.081
perl Makefile.PL
make
make test
su -c "make install"

Installing the SNMP::Monitor package is just as simple. You will be prompted a lot of questions that should hopefully be self explaining. I hope the defaults are fine.

For installing the HTML pages, see the docs of the HTML::EP module by doing a

perldoc HTML::EP

this should tell you how to configure your WWW server for feeding files with the extension .ep into the HTML::EP system. To verify the installation, create a file like

<ep-perl>
print "content-type: text/plain\n\n"; print "It worked! Your EP system is up and running.\n"; </ep-perl>

and point your browser to the appropriate location (note: Don't use a location like file://..., but http://...!). You should neither see the C<ep-perl> nor the C<print> instructions.

After this is done, select a password protected directory and put the files from the "html" directory into it. That's all.

You might start the "snmpmon" utility when the system comes up. See "Starting the monitor" and "Stopping the monitor" below for instructions what to perform when booting or shutting down.

Finally you should manually edit the configuration file. This is by default located in

/etc/snmpmon/configuration

but you might have choosen another location while installing the module. Note that what you are editing is Perl source! You are bound to the restrictions and you have all the power of Perl in this file. However, when done editing, do yourself a favour and check, whether you have created correct Perl code again by doing a

perl -e 'require "/etc/snmpmon/configuration"; print "ok\n"'

For a detailed description of the configuration file, see

perldoc SNMP::Monitor::Install

4.) Adding routers

While installing the SNMP::Monitor package, a file like "/etc/snmpmon/configuration" should have been created for you. Typically it includes one router. Of course you are by no means restricted to a single router: You can add more routers at any time by doing a

snmpmon --add <routername>

5.) Removing routers

When playing with the configuration file, you might need to remove a router. This can be done with

snmpmon --remove <routername>

6.) Starting the monitor

Once you have initialized the system, try a

snmpmon --start

snmpmon start

If something goes wrong, you should receive an email that tells you an error message.

7.) Shutting down the monitor

When the system is shutting down, you can do a

snmpmon --stop

snmpmon stop

Note, that no accounting information is created in that time!

8.) Author and Copyright

This program is

        Copyright (C) 1998    Jochen Wiedmann
                              Am Eisteich 9
                              72555 Metzingen
                              Germany

                              Phone: +49 7123 14887
                              Email: joe@ispsoft.de

You may distribute this module under the terms of either the GNU General Public License or the Artistic License, as specified in the Perl README file.

9. See also

the SNMP::Monitor(3) manpage, the snmpmon(1) manpage, the SNMP(3) manpage