Cisco CATALYST 3920 24 PORT TOKEN RING SWITCH Specification Guide
Introduction to the Catalyst 3920 1-5
RMON Support
RMON is an industry-standard method for providing network statistics monitoring using SNMP. It
also collects fault, performance, and configuration statistics. RMON can monitor continuously, even
when communication with the management station is not possible or efficient. It can then notify the
management station when an exceptional condition occurs.
also collects fault, performance, and configuration statistics. RMON can monitor continuously, even
when communication with the management station is not possible or efficient. It can then notify the
management station when an exceptional condition occurs.
In typical SNMP management, the SNMP client has to continuously poll the Catalyst 3920 for fault,
performance, and configuration information while waiting for the value to change. This causes
increased traffic through the network. With RMON, you can have the switch monitor a particular
statistic internally, and when the statistic reaches a threshold, the Catalyst 3920 will send a trap to
the client. This monitoring method reduces traffic between the SNMP client and the Catalyst 3920
switch.
performance, and configuration information while waiting for the value to change. This causes
increased traffic through the network. With RMON, you can have the switch monitor a particular
statistic internally, and when the statistic reaches a threshold, the Catalyst 3920 will send a trap to
the client. This monitoring method reduces traffic between the SNMP client and the Catalyst 3920
switch.
As an option, the Catalyst 3920 provides RMON support statistics, history, alarms, and events. It
also provides support for the following groups of the Token Ring extensions to the Remote Network
Monitoring MIB (RFC 1513):
also provides support for the following groups of the Token Ring extensions to the Remote Network
Monitoring MIB (RFC 1513):
•
MAC-layer Statistics Group
A collection of MAC-layer statistics kept for each Token Ring interface, such as the total number
of MAC packets received and the number of times the port entered a beaconing state.
of MAC packets received and the number of times the port entered a beaconing state.
•
Promiscuous Statistics Group
A collection of promiscuous statistics kept for non-MAC packets on each Token Ring interface,
such as the total number of good non-MAC frames received that were directed to an LLC
broadcast address.
such as the total number of good non-MAC frames received that were directed to an LLC
broadcast address.
•
Token Ring Ring Station Group
A collection of statistics and status information associated with each Token Ring station on the
local ring. In addition, this group provides status information for each ring being monitored.
local ring. In addition, this group provides status information for each ring being monitored.
•
Token Ring Ring Station Order Group
A listing of the order of stations on the monitored rings.
You can use an external RMON probe for full RMON support.
Access to RMON data is available only via an SNMP management application that supports RFC
1757 and RFC 1513. You cannot access RMON via the Catalyst 3920 console interface; however,
the console statistics provide similar information. For full utilization of RMON data, you should use
Cisco’s TrafficDirector.
1757 and RFC 1513. You cannot access RMON via the Catalyst 3920 console interface; however,
the console statistics provide similar information. For full utilization of RMON data, you should use
Cisco’s TrafficDirector.
Network Traffic Monitoring
To aid in network management, the Catalyst 3920 allows you to copy traffic from any Token Ring
port to the Switched Port Analyzer (SPAN) port. You can then attach an external Token Ring monitor
(network analyzer) or RMON probe to the SPAN port. Forwarding to the SPAN port takes place
independently of the normal forwarding.
port to the Switched Port Analyzer (SPAN) port. You can then attach an external Token Ring monitor
(network analyzer) or RMON probe to the SPAN port. Forwarding to the SPAN port takes place
independently of the normal forwarding.
Self-Diagnostics
The Catalyst 3920 performs a self-diagnostic test when it is powered on. The results of these
diagnostics are displayed at the console and saved in a diagnostic test results file, which can be
viewed later from the console. System information and warning messages are displayed at the
console and saved in a message log file, which may also be viewed later from the console. The
message log file is not preserved across a system reset.
diagnostics are displayed at the console and saved in a diagnostic test results file, which can be
viewed later from the console. System information and warning messages are displayed at the
console and saved in a message log file, which may also be viewed later from the console. The
message log file is not preserved across a system reset.