Cisco ONS 15327 Procedure Manual page 130

NTP-B34 Create Ethernet RMON Alarm Thresholds
From the Sample Type pull-down menu, choose either Relative or Absolute. Relative restricts the
Step 8
threshold to use the number of occurrences in the user-set sample period. Absolute sets the threshold to
use the total number of occurrences, regardless of time period.
Type in an appropriate number of seconds for the Sample Period.
Step 9
Type in the appropriate number of occurrences for the Rising Threshold.
Step 10
Note
Enter the appropriate number of occurrences in the Falling Threshold field. In most cases a falling
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threshold is set lower than the rising threshold.
A falling threshold is the counterpart to a rising threshold. When the number of occurrences is above the
rising threshold and then drops below a falling threshold, it resets the rising threshold. For example,
when the network problem that caused 1001 collisions in 15 minutes subsides and creates only 799
collisions in 15 minutes, occurrences fall below a falling threshold of 800 collisions. This resets the
rising threshold so that if network collisions again spike over a 1000 per 15 minute period, an event again
triggers when the rising threshold is crossed. An event is triggered only the first time a rising threshold
is exceeded (otherwise a single network problem might cause a rising threshold to be exceeded multiple
times and cause a flood of events).
Click OK to complete the procedure.
Step 12
Table 3-2
Variable
iflnOctets
iflnUcastPkts
ifInMulticastPkts
ifInBroadcastPkts
ifInDiscards
iflnErrors
ifOutOctets
ifOutUcastPkts
ifOutMulticastPkts
ifOutBroadcastPkts
Cisco ONS 15327 Procedure Guide, R4.0
3-24
For a rising type of alarm, the measured value must move from below the falling threshold to
above the rising threshold. For example, if a network is running below a falling threshold of 400
collisions every 15 seconds and a problem causes 1001 collisions in 15 seconds, these
occurrences raise an alarm.
Ethernet Threshold Variables (MIBs)
Definition
Total number of octets received on the interface, including
framing octets
Total number of unicast packets delivered to an appropriate
protocol
Number of multicast frames received error free
The number of packets, delivered by this sub-layer to a higher
(sub-)layer, which were addressed to a broadcast address at this
sub-layer
The number of inbound packets which were chosen to be
discarded even though no errors had been detected to prevent
their being deliverable to a higher-layer protocol
Number of inbound packets discarded because they contain
errors
Total number of transmitted octets, including framing packets
Total number of unicast packets requested to transmit to a single
address
Number of multicast frames transmitted error free
The total number of packets that higher-level protocols requested
be transmitted, and which were addressed to a broadcast address
at this sub-layer, including those that were discarded or not sent
Chapter 3 Turn Up Node
March 2003