Thresholding on the
system is used to monitor the system for conditions that could potentially
cause errors or outage. Typically, these conditions are temporary (i.e. high
CPU utilization, or packet collisions on a network) and are quickly resolved.
However, continuous or large numbers of these error conditions within a
specific time interval may be indicative of larger, more severe issues. The
purpose of thresholding is to help identify potentially severe conditions so
that immediate action can be taken to minimize and/or avoid system downtime.
thresholding models are supported by the system:
Alert: A value is
monitored and an alert condition occurs when the value reaches or exceeds the
configured high threshold within the specified polling interval. The alert is
then generated and/or sent at the end of the polling interval.
In the example
shown in the figure below, this model generates alerts during period 2, 3, and
5 at the point where the count exceeded HT.
Alarm: Both high and low
thresholds are defined for a value. An alarm condition occurs when the value
reaches or exceeds the configured high threshold within the specified polling
interval. The alert is then generated and/or sent at the end of the polling
The alarm is
cleared at the end of the first interval where the measured value is below the
In the example
shown in in the figure below, this model generates an alarm during period 2
when the count exceeds HT. A second alarm is generated in period 6 when the
count falls beneath LT. The second alarm indicates a "clear" condition.
Figure 1. Example of
Note that for
certain values, the alert or alarm serves to warn of low quantities (i.e.
memory, session licenses, etc.). In these cases, the low threshold is the
condition that must be met or exceeded within the polling interval to generate
the alert or alarm. Once the high threshold is exceeded during an interval, the
low quantity condition is cleared.
functionality on the system can be configured to monitor the following values:
Authentication failure rate
request queue usage
ASN GW Service:
ASN GW Authentication failures
ASN GW hand-off denials
number of EAP retries
network entry denials
Network Access Identifier (NAI) in R6 message
timeout duration during session setup
session timeout duration
registration reply errors
Reply, Re-registration Reply, and De-registration Reply errors
failed and discarded
call setup failures
calls rejected due to no processing resources being available
MME Authentication failures
MME Session Attachment failures
software task utilization
IP address pool
packets forwarded to CPU
CompactFlash memory utilization
conditions using one of the following mechanisms:
SNMP traps: SNMP traps
have been created that indicate the condition (high threshold crossing and/or
clear) of each of the monitored values. Complete descriptions and other
information pertaining to these traps is located in the
starentMIB(8164).starentTraps(2) section of the
SNMP MIB Reference.
of specific traps can be enabled or disabled on the system allowing you to view
only those traps that are most important to you.
Logs: The system
provides a facility called threshold for which active and event logs can be
generated. As with other system facilities, logs are generated Log messages
pertaining to the condition of a monitored value are generated with a severity
level of WARNING.
Refer to the
System Administration Guide for additional information on system logging
Alarm System: High
threshold alarms generated within the specified polling interval are considered
"outstanding" until a the condition no longer exists and/or a condition clear
alarm is generated.
alarms are reported to through the system\'s alarm subsystem and are viewable
through the system\'s CLI.
table indicates the reporting mechanisms supported by each of the above models.
Table 1 Thresholding
Reporting Mechanisms by Model