Enterasys X-Pedition XSR, Cli Reference Manual

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Policy-Map Commands
12-92 Configuring Quality of Service
XSR(config)#policy-map policy75
XSR(config-pmap<policy75>)#class acl203
XSR(config-pmap-c<acl203>)#bandwidth percent 35
XSR(config-pmap-c<acl203>)#queue-limit 50
random-detect (RED)
This command configures RED for a policy map.
This command configures and enables Random Early Detect (RED) for the class. RED is a
congestion avoidance mechanism that slows traffic by randomly dropping packets during
congestion and is useful with protocols like TCP that respond to dropped packets by reducing the
transmission rate. While RED may be implemented using WRED, this command is retained for
compatibility with earlier releases and simplicity of configuration when only RED is required.
Syntax
random-detect min-thres max-thres [ mark-prob ]
Syntax of the “no” Form
The no form of this command disable RED on an interface:
no random-detect
Mode
Policy ‐ Map Class configuration: XSR(config-pmap-c-< xx> )#
Defaults
• Disabled
• Mark ‐ prob: 10
Example
The following example enables RED. The minimum and maximum thresholds are 24 and 40 ,
respectively. The dropping probability is 1/4.
XSR(config)#policy-map foobar
XSR(config-pmap<foobar>)#class alpha
XSR(config-pmap-c<alpha>)#random-detect 24 40 4
min-thres
Peak limit of average packet queue length, ranging from 1 to 4096, beyond
which the XSR randomly drops packets.
max - thres
Peak limit of average packet queue length, ranging from 1 to 4096, beyond
which all packets are dropped.
mark-prob
Mark probability denominator, ranging from 1 to 65,536. This is the liklihood
of queued packets being dropped when their number exceeding the
minimum threshold is between 0 and (1/ mark ‐ prob ). When the peak threshold
is reached, drop probability is 1 divided by the peak probability.