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NAME

       mrtg-unix-guide - The MRTG 2.16.3 Linux/Unix Installation Guide

DESCRIPTION

       MRTG comes to you in Source Code. This means that you have to compile
       parts of it before you can use it on a Unix machine. These instructions
       help you to do so.

PREPARATION

       In order to compile and use mrtg you need a C compiler and a copy of
       perl installed on your machine. In most cases this will already be
       available.  In case it is not, here are some starting points. Below
       I’ll give you a detailed run through the whole compilation process.

       GCC The GNU C compiler comes preinstalled on most of the free Unicies
           out there.  For commercial derivatives you may have to download and
           compile it first. If you have no compiler at all there is a chicken
           and egg problem, but there are also precompiled versions of gcc
           available for most operating systems.

            http://gcc.gnu.org/

       Perl
           Large parts of the MRTG system are written in the Perl scripting
           language.  Make sure there is a recent copy of perl on your machine
           (try perl -v). At least version 5.005 is required for mrtg to work
           well. If you use SNMPV3 and other new features you should use at
           least 5.8.

           You can get the latest perl from

            http://www.perl.com/

       MRTG generates traffic graphs in the PNG format. To be able to do this
       it needs several 3rd party libraries. When compiling these libraries I
       urge you to make sure you compile them as static libraries. There is
       just much less trouble ahead if you are doing it like this. See the
       Instructions in the next section for inspiration. Note that many free
       unices have all the required libraries already in place so there is no
       need to install another copy. To check it is best to skip all the
       library instructions below and go straight into the mrtg compile.

       If the first attempt fails and you do not get a working version of
       mrtg, try compiling new copies of all libraries as explained below. Do
       this BEFORE you send email to me about problems compiling mrtg.

       gd  This is a basic graph drawing library created by Thomas Boutell.
           Note that all releases after Version 1.3 only create PNG images.
           This is because a) Thomas got into trouble because the GIF format
           which it used to produce uses a compression technology patented by
           Unisys. b) PNG is more efficient and patent free. MRTG can work
           with old and new version of the GD library. You can get a recent
           copy of GD from:

            http://www.boutell.com/gd/

       libpng
           Is required by gd in order to produce PNG graphics files. Get it
           from:

            http://www.libpng.org/pub/png/libpng.html

       zlib
           Is needed by libpng to compress the graphics files you create.  Get
           a copy from

            http://www.gzip.org/zlib

       And last but not least you also need mrtg itself. In case you have not
       yet downloaded it, you can find a copy on my website:

        http://oss.oetiker.ch/mrtg/pub

LIBRARY COMPILATION

       In this section I will give you step by step instructions on how to
       compile the various libraries required for the compilation of mrtg.
       Note that these libraries may already be installed if you have a *BSD
       or Linux system so you can skip recompiling them. The wget program used
       below is a simple web downloader. You can also enter the address into
       your netscape if you don’t have wget available.

       First let’s create a directory for the compilation. Note that this may
       already exist on your system. No problem, just use it.

        mkdir -p /usr/local/src
        cd /usr/local/src

       If you do not have zlib installed:

        wget http://www.zlib.net/zlib-1.2.3.tar.gz
        gunzip -c zlib-*.tar.gz | tar xf -
        rm zlib-*.tar.gz
        mv zlib-* zlib
        cd zlib
        ./configure
        make
        cd ..

       If you don’t have libpng installed

        wget ftp://ftp.simplesystems.org/pub/libpng/png/src/libpng-1.2.40.tar.gz
        gunzip -c libpng-1.2.34.tar.gz | tar xf -
        mv libpng-* libpng
        cd libpng
        env CFLAGS="-O3 -fPIC" ./configure --prefix=$INSTALL_DIR
        make
        rm *.so.* *.so
        cd ..

       And now you can compile gd

       For versions up to 1.8.4, try:

        wget http://www.boutell.com/gd/http/gd-1.8.4.tar.gz
        gunzip -c gd-*.tar.gz |tar xf -
        rm gd-*.tar.gz
        mv gd-* gd
        cd gd

       The \ characters at the end of the following lines mean that all the
       following material should actually be written on a single line.

        perl -i~ -p -e s/gd_jpeg.o//g Makefile
        make INCLUDEDIRS="-I. -I../zlib -I../libpng" \
             LIBDIRS="-L../zlib -L. -L../libpng" \
             LIBS="-lgd -lpng -lz -lm" \
             CFLAGS="-O -DHAVE_LIBPNG"
        cd ..

       For versions starting around 2.0.11, try:

        wget http://www.boutell.com/gd/http/gd-2.0.33.tar.gz
        gunzip -c gd-2.0.33.tar.gz |tar xf -
        mv gd-2.0.33 gd
        cd gd
        env CPPFLAGS="-I../zlib -I../libpng" LDFLAGS="-L../zlib -L../libpng" \
            ./configure --disable-shared --without-freetype --without-jpeg
        make
        cp .libs/* .

MRTG COMPILATION

       Ok, now everything is ready for the mrtg compilation.

        cd /usr/local/src
        gunzip -c mrtg-2.16.3.tar.gz | tar xvf -
        cd mrtg-2.16.3

       If all the libraries have been preinstalled on your system you can
       configure mrtg by doing a simple:

        ./configure --prefix=/usr/local/mrtg-2

       Otherwise you may have to give some hints on where to find the various
       libraries required to compile mrtg:

        ./configure --prefix=/usr/local/mrtg-2       \
                    --with-gd=/usr/local/src/gd      \
                    --with-z=/usr/local/src/zlib     \
                    --with-png=/usr/local/src/libpng

       If you have RRDtool available you might want to tell mrtg about it so
       that you can opt to use rrdtool with mrtg. Check mrtg-rrd.

       Configure will make sure your environment is fit for building mrtg.  If
       it finds a problem, it will tell you so and it will also tell you what
       to do about it. If everything is OK, you will end up with a custom
       Makefile for your system. Now type:

        make

       This builds the rateup binary and edits all the perl pathnames in the
       scripts. You can now install mrtg by typing

        make install   (requires gnu install)

       All the software required by MRTG is now installed under the
       /usr/local/mrtg-2 subdirectory.

       You can now safely delete the libraries we compiled above. Then again,
       you might want to keep them around so that you have them available when
       compiling the next version of mrtg.

CONFIGURATION

       The next step is to configure mrtg for monitoring a network device.
       This is done by creating an mrtg.cfg file which defines what you want
       to monitor. Luckily, you don’t have to dive straight in and start
       writing your own configuration file all by yourself. Together with mrtg
       you also got a copy of cfgmaker. This is a script you can point at a
       router of your choice; it will create a mrtg configuration file for
       you. You can find the script in the bin subdirectory.

        cfgmaker --global 'WorkDir: /home/httpd/mrtg'  \
                 --global 'Options[_]: bits,growright' \
                 --output /home/mrtg/cfg/mrtg.cfg    \
                  community@router.abc.xyz

       This example above will create an mrtg config file in /home/mrtg/cfg
       assuming this is a directory visible on your webserver. You can read
       all about cfgmaker in cfgmaker. One area you might want to look at is
       the possibility of using --ifref=ip to prevent interface renumbering
       troubles from catching you.

       If you want to start rolling your own mrtg configuration files, make
       sure you read mrtg-reference to learn all about the possible
       configuration options.

RUNNING MRTG

       Once you have created a configuration file, try the following:

        /usr/local/mrtg-2/bin/mrtg /home/mrtg/cfg/mrtg.cfg

       This will query your router and also create your first mrtg trafic
       graphs and webpages. When you run mrtg for the first time there will be
       a lot of complaints about missing log files. Don’t worry, this is
       normal for the first 2 times you start mrtg. If it keeps complaining
       after this time you might want to look into the problem.

       Starting mrtg by hand is not ideal in the long run. So when you are
       satisfied with the results you can automate the process of running mrtg
       in regular intervals (this means every 5 minutes by default).

       You can either add mrtg to your crontab with a line like this:

        0,5,10,15,20,25,30,35,40,45,50,55 * * * * \
              <mrtg-bin>/mrtg <path to mrtg-cfg>/mrtg.cfg \
                       --logging /var/log/mrtg.log

       or if you live in Linux Land the line may look like this if you are
       using "crontab -e"

        */5 * * * *  <mrtg-bin>/mrtg <path to mrtg-cfg>/mrtg.cfg \
                              --logging /var/log/mrtg.log

       or like this if you use /etc/crontab

        */5 * * * *  mrtg-user  <mrtg-bin>/mrtg <path to mrtg-cfg>/mrtg.cfg \
                                        --logging /var/log/mrtg.log

       You can also run mrtg as a daemon process by adding the line

        RunAsDaemon: Yes

       to your mrtg configuration file and then creating a startup script in
       your system startup sequence. Unfortunately, adding startup scripts
       differs widely amongst different unix systems. The modern ones normally
       have a directory called /etc/init.d or /etc/rc.d/init.d where you put
       scripts which starts the process you want to run when the system boots.
       Further you must create a symbolic link in /etc/rc3.d or
       /etc/rc.d/rc?.d called S65mrtg (this is just a sample name ... it is
       just important that it starts with S followed by a two digit number).
       If you are not sure about this, make sure you consult the documentation
       of your system to make sure you get this right.

       A minimal script to put into init.d might look like this:

        #! /bin/sh
        cd /usr/local/mrtg-2.16.3/bin && ./mrtg --user=mrtg-user \
              /home/httpd/mrtg/mrtg.cfg  --logging /var/log/mrtg.log

       Note that this will only work with RunAsDaemon: Yes in your mrtg.cfg
       file.

AUTHOR

       Tobias Oetiker <tobi@oetiker.ch>