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Basic Dial NMS Implementation Guide
Task 3Using MRTG to Monitor and Graph
Traffic Loads
About MRTG
Multi Router Traffic Grapher (MRTG) is a free performance management application for Unix that
monitors SNMP statistics from any SNMP capable device on your network and performs the following
functions:
Captures, stores, and graphically presents SNMP data. By default, a web page with four graphs per
MIB object (OID) is created by MRTG. The graphs show the variation of MIB data over time.
Runs from the crontab. Every five minutes, a cron job runs MRTG to query a user-configured list
of OIDs and network devices. After each data collection cycle, the MRTG perl script posts updated
graphs to a web page.
Efficiently compresses and archives data samples to create graphs.
Enables you to determine if trending data is useful for monitoring your environment before you
invest in costly network performance software. If trending data is critical to manage your network,
it may be necessary to purchase a commercial network performance package, such as Concord
Network Health. However, you may find that MRTG is all you need.
Figure 10
MRTG Polls for OIDs; OID Values that Are Returned to MRTG
35193
Polling OID
Returning OID valves
Cisco
IOS
devices
MRTG
