2. Installation process
 

The installation process will be presented just for a non-distributed implementation. 
A distributed implementation follows the same instructions but needs modifications on path specification. 

Note: This document is focused on the Windows version of MRTG. The Unix version does basically follow the same installation procedure. For UNIX instructions go to http://people.ee.ethz.ch/~oetiker/webtools/
 

2.1 Installing Perl

Perl has to be installed on the MRTG machine following the setup instructions. Make sure the Perl path (where you perl.exe resides) is part of your system’s PATH variable. 

2.2 Installing MRTG

MRTG comes as an archive of Perl scripts, configuration files, documentation and also the source files. It does not require specific installation tasks. Just decompress the MRTG files in the chosen MRTG folder. 
Make sure your system’s PATH variable contains the MRTG “bin” directory. 

2.3 Running the HTTP server

As MRTG produces the variation .PNG graphs and .HTML files, they can be delivered over a web interface. MRTG also offers a script to construct the index html files, which summarizes the rest of the html files for each monitored host. 

The Web server setup does require the following steps: 

- Create a “virtual site” for the MRTG web interface and specify the home directory where the MRTG’s .html and .png files reside. 
- For each monitored host, MRTG is able to construct the index.html file. It is recommended to place the files for each monitored host in a separate directory. At the root level of your MRTG folder hierarchy create a global index.html file, which makes references to the hosts’ individual index.html files. 

2.4 Enabling SNMP support on the monitored hosts
      Extended SNMP support for Windows based hosts (cpu, memory, disk, etc)

The majority of OSs do not have the SNMP support enabled by default. The SNMP software has to be installed or enabled in order to get the SNMP OID data collection working. The SNMP support offers the SNMP client, which listens for SNMP requests comming from a NMS (network management station) and delivers the requested SNMP values.

A SNMP daemon/service requires the following generic information to be specified:

- "comunity name" // generic name which offers a basic security level. The default value is "public". A comunity is associated with some of the following rights: read/write/create/notify.
- "contact"  and "location" are descriptional values to personalize the host.
- "trap destinations" // NMSs where the host is able to send SNMP traps notifcations.
- "accept SNMP packets" // introduces a higher security level by accepting SNMP requests only from certain NMSs.

The SNMP support installation for the most popular platforms:

1. Windows NT4 offers the SNMP service through ControlPanel -> Network -> Services where the Add/Remove Services option installs the SNMP support.

2. Windows 2000 offers the SNMP service through ControlPanel -> AddRemoveSoftware -> WindowsComponents

3. UNIX based hosts need the SNMPD daemon to be configured (edit the config file) and started (edit the .RC file). Check the specific SNMPD setup in the product documentation.

4. Cisco routers/switches offer SNMP support running on a "public" community for CatOS based switches and no community nameset for IOS based routers/switches by default. 

Some sample IOS commands that change the SNMP configuration: 

(config)#snmp-server community <name> <access-type>
(config)#snmp-server contact <text>
(config)#snmp-server enable traps [notification-type]
(config)#snmp-server host <host-addr> 

To get the full snmp service options read the Cisco IOS documentation / Cisco CatOS documentation or get the CLI (command line) help on the "snmp-server / set snmp" commands.
 

Extended SNMP OID support for Windows based hosts (cpu, memory, disk, dhcp, dns, web, etc)

Microsoft Windows NT/2000 offer a limited set of SNMP OIDs by default. The most interesting ones are getting installed only by additional software services or packages. In order to install the SNMP OID support for CPU, Memory, Disks, etc you need to install the ResourceKit package which comes with additional features to the OS (requires additional license).

The SNMP OID support included in the ResourceKit can be installed seprately without installing the whole ResourceKit.
A copy of the SNMP support files can be obtained from the SNMP for the Public Comunity website (SNMP4PC) where a standard (no license required) and full SNMP support (ResourceKit license required) packages are available.

The list of the OID counters that will become available in your Windows system is: WindowsNT and Windows2000