The Multi Router Traffic Grapher or just simply MRTG is free software for monitoring the traffic load on network links. It allows the user to see traffic load on a network over time in graphical form. MRTG generates HTML pages containing graphical images which provide a LIVE visual representation of this traffic. How does it work? MRTG uses the Simple Network Management Protocol (SNMP) to send requests with two object identifiers (OIDs) to a device. The device, which must be SNMP-enabled, will have a management information base (MIBs) to lookup the OID’s specified. After collecting the information it will send back the raw data encapsulated in an SNMP protocol. MRTG records this data in a log on the client along with previously recorded data for the device. The software then creates an HTML document from the logs, containing a list of graphs detailing traffic for the selected device.

This is a “How to” for installing MRTG (2.9.17) on a cpanel server. Let’s start:

# Download the software (http://SERVER_IP/mrtg) and move it to your download folder on your server. Or use the RPM installation information further down below.
cd /root/downloads

# Unninstall any older version in case we have an old/broken installation
rpm -e mrtg

# Get the latest rpm. The RPM might not reflect the latest available stand-alone version
wget http://SERVER_IP/mrtg
# Or grab a newer version from here: http://SERVER_IP/mrtg

# Installing the application
rpm -Uvh mrtg-2.9.17-1cpanel.i386.rpm

# Moving libpng
cd /usr/lib
mv libpng.so.2 libpng.so.2.OLD

# Creating the symlink
ln -s libpng.so.3 libpng.so.2

# Edit language at and specify only “en_US”
pico /etc/sysconfig/i18n

# Restarting MRTG
service mrtg restart

# Configure MRTG to allow only your local IP to see the reports at http://SERVER_IP/mrtg – Important: If your local IP changes due to DHCP very often, you should skip this step.
# This can be happening often when being on DSL.

pico /usr/local/apache/conf/httpd.conf

#Search for the line (CTRL+W):
# It should look like this:

Options Indexes FollowSymlinks MultiViews
AllowOverride None
Order allow,deny
Allow from all

#After the last line () paste this and change allowed IPs:

order deny,allow
allow from [ SERVER IP ]
allow from [YOUR LOCAL IP]
deny from all

# Restarting httpd
service httpd restart

# Let’s put MRTG to start with the system
chkconfig –level 0123456 mrtg on

# Important: Add MRTG to the up2date skip-list of your server. If you don’t do this, after the system updates your MRTG installation will be broken.
up2date –configure
# Select the skip-list option
# Add mrtg to the skip-list
“mrtg*”

Thats it….