Foundry NetIron M2404C and M2404F Metro Access Switches
Configuring RMON (Rev. 03)
Remote Monitoring (RMON)
© 2008 Foundry Networks, Inc.
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Remote Monitoring (RMON)
Remote Monitoring (RMON) is a standard monitoring specification that enables various network
monitors and console systems to exchange network-monitoring data. RMON provides network
administrators with more freedom in selecting network-monitoring probes and consoles with
features that meet their particular networking needs.
The RMON specification defines a set of statistics and functions that can be exchanged between
RMON-compliant console managers and network probes. As such, RMON provides network
administrators with comprehensive network-fault diagnosis, planning, and performance-tuning
information.
Overview
Packets Definitions
Good Packets
Good packets are error-free packets that have a valid frame length. For example, on Ethernet, good
packets are error-free packets that are between 64 and 1518 octets long. They follow the form
defined in IEEE 802.3.
Bad Packets
Bad packets are packets that have proper framing and are therefore recognized as packets, but
contain errors within the packet or have an invalid length. For example, on Ethernet, bad packets
have a valid preamble and
Start of Frame Delimiter (
SFD), but have a bad Cyclic Redundancy Check
(CRC) or are either shorter than 64 octets or longer than 1518 octets.
RMON Groups
The switches support the following four RMON groups:
•
Statistics (group 1)
•
History (group 3)
•
Alarms (group 4)
•
Events (group 5).
The Ethernet Statistics Group
The Ethernet Statistics group contains statistics of packets, bytes, broadcasts, multicasts, and errors,
measured by the probe for each monitored Ethernet interface on the switch.
Information from the Statistics group is used to detect changes in traffic and error patterns in
critical areas of the network.
The History Group
The History group provides historical views of network performance by taking periodic samples of
the counters supplied by the Statistics group.
The group is useful for analyzing traffic patterns and trends on an Ethernet interface on the switch
and for establishing baseline information indicating normal operating parameters.