Rate Statistics; Event Statistics; Bulk Statistics Support For Qos Statistics - Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - QUALITY OF SERVICE CONFIGURATION GUIDE 2010-09-22 Configuration Manual

JunosE 11.3.x Quality of Service Configuration Guide

Rate Statistics

Event Statistics

Bulk Statistics Support for QoS Statistics

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Committed drop threshold—Threshold above which committed drop rate events are
counted.
Conformed drop threshold—Threshold above which conformed drop rate events are
counted.
Exceeded drop threshold—Threshold above which exceeded drop rate events are
counted.
You can configure the E Series router to gather statistics for the rate at which queues
forward and drop packets.
Queue rate statistics measure the forwarding and drop rates of each queue in bits per
second. All bytes in the Layer 2 encapsulation are included in the rate calculation. For
example, rates for a queue on Ethernet include the Ethernet and VLAN encapsulations.
For ATM modules, you can optionally configure queue statistics and queue rates to
include the cell encapsulation and padding. Cell encapsulation and padding are referred
to as the cell tax. The QoS shaping mode that you set on ATM line modules determines
whether queue rate statistics include cell tax.
If the interface is configured with frame-based QoS shaping mode, the egress queue
measures frame rate statistics; an ATM cell tax is not included.
If the interface is configured with cell-based QoS shaping mode, the egress queue
measures cell rate statistics; cell rates include ATM Adaptation Layer 5 (AAL5)
encapsulation and cell padding.
If the interface is configured with byte adjustment, the egress queue measures rate
statistics that are adjusted to the byte adjustment value.
NOTE: If you change the QoS shaping mode value in the middle of a rate
period, the gathered rates are a mixture of cell- and frame-based rates for
that one rate period. The next rate period uses a rate based on the new
QoS shaping mode setting.
You can configure the E Series router to count the number of times that forwarding or
drop rates exceed a specific threshold. Events can be useful when you are monitoring
service level agreements. For example, you might count the number of times that the
drop rate of a queue is nonzero.
You can obtain queue-level QoS statistics for each logical interface by querying the SNMP
MIB. However, using SNMP to obtain queue-level statistics consumes significant network
bandwidth because SNMP polls large volumes of data frequently. As an alternative to
using the SNMP MIB, you can use the bulkstats statistics application.
Copyright © 2010, Juniper Networks, Inc.