Rmon And The Switch; Rmon Features Of The Switch - 3Com 9100 User Manual

122 C 8: S
HAPTER TATUS
RMON and the
Switch
RMON Features of
the Switch
M S
ONITORING AND TATISTICS
An RMON probe, however, autonomously looks at the network on behalf
of the management workstation without affecting the characteristics and
performance of the network. The probe reports by exception, which
means that it only informs the management workstation when the
network has entered an abnormal state.
RMON requires one probe per LAN segment, and stand-alone RMON
probes have traditionally been expensive. Therefore, 3Com's approach
has been to build an inexpensive RMON probe into the agent of each
switch. This allows RMON to be widely deployed around the network
without costing more than traditional network management.
For example, statistics can be related to individual ports and the switch
can take autonomous actions such as disabling a port (temporarily or
permanently) if errors on that port exceed a predefined threshold. Also,
since a probe must be able to see all traffic, a stand-alone probe must be
attached to a nonsecure port. Implementing RMON in the switch means
that all ports can have security features enabled.
Table 35 details the RMON support provided by the Switch 9100.
Table 35 RMON Support Supplied By the Switch 9100
RMON Group
Statistics
History
Alarms
Events
Support Supplied by the Switch
The switch supports the EtherStats group.
A new or initialized switch has two History sessions on each
port:
30-second intervals
2-hour intervals
The switch can store a maximum of 50 History sessions.
The switch supports up to 50 alarms. You can enter or delete
these alarms using an RMON management application.
A new or initialized switch has events defined for use with the
default alarm system.