Extreme 3804 User Guide

Page of 227
12-16
S
UMMIT
 S
WITCH
 I
NSTALLATION
 
AND
 U
SER
 G
UIDE
S
TATUS
 M
ONITORING
 
AND
 S
TATISTICS
A
LARMS
The Alarms group provides a versatile, general mechanism for setting threshold and 
sampling intervals to generate events on any RMON variable. Both rising and falling 
thresholds are supported, and thresholds can be on the absolute value of a variable or 
its delta value. In addition, alarm thresholds may be autocalibrated or set manually.
Alarms inform you of a network performance problem and can trigger automated 
action responses through the Events group.
E
VENTS
The Events group creates entries in an event log and/or sends SNMP traps to the 
management workstation. An event is triggered by an RMON alarm. The action taken 
can be configured to ignore it, to log the event, to send an SNMP trap to the receivers 
listed in the trap receiver table, or to both log and send a trap. The RMON traps are 
defined in RFC 1757 for rising and falling thresholds.
Effective use of the Events group saves you time. Rather than having to watch real-time 
graphs for important occurrences, you can depend on the Event group for notification. 
Through the SNMP traps, events can trigger other actions, providing a mechanism for 
an automated response to certain occurrences.
RMON 
AND
 
THE
 S
WITCH
RMON requires one probe per LAN segment, and standalone RMON probes have 
traditionally been expensive. Therefore, Extreme’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. The Summit accurately maintains RMON statistics at the maximum line 
rate of all of its ports.
For example, statistics can be related to individual ports. Also, because 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.
Summit.bk : 12STATUS.FM  Page 16  Thursday, June 18, 1998  9:27 AM