Switch Configuration Guide

clear policy port-hit Configuring Policy Class of Service (CoS)
Enterasys Matrix DFE-Gold Series Configuration Guide 8-21
Configuring Policy Class of Service (CoS)
Using Port-Based or Policy-Based CoS Settings
TheEnterasysMatrixSeriesdevicesupportsClassofService(CoS),whichallowsyoutoassign
mission‐criticaldatatohigherprioritythroughthedevicebydelayinglesscriticaltrafficduring
periodsofcongestion.Thehigherprioritytrafficthroughthedeviceisservicedfirstbeforelower
prioritytraffic.TheClassofService
capabilityofthedeviceisimplementedbyapriorityqueueing
mechanism.ClassofServiceisbasedontheIEEE802.1D(802.1p)standardspecific ation,and
allowsyoutodefineeightpriorities(0‐7,with7grantedhighestpriority)and,dependingonport
type,upto16transmitqueues(0‐15)of
trafficforeachport.
EnterasysNetworks’enhancedCoSimplementationallowsyoutousethefollowingmethodsto
configureClassofServiceontheEnterasysMatrixSeriesdevice:
• Allowingthedevicetoautomaticallyassignpolicy‐basedinboundratelimitersandtransmit
queuesasdescribedinthissection.
• Configuringtransmitqueueingandratelimiting
onaper‐portbasisasdescribedin
Chapter 22.
Bydefult,policy‐basedCoSisdisabledonthedevice,anddefaultoruser‐assignedport‐based
802.1D(802.1p)settingsareusedtodeterminetransmitqueuesandtrafficratelimiting.When
policy‐basedCoSisenabled,thedefaultanduser‐assignedsettings
willoverrideport‐based
settingsdescribedinChapter 22.
About Policy-Based CoS Default and User-Defined Configurations
Onceenabledusingthesetcosstatecommandasdescribedin“setcosstate”onpage 8‐23,the
policy‐basedCoSfunctionprovidesthefollowingdefaultconfiguration:
•Transmitqueues(TXQ)—Astrict‐priorityqueueingmechanismwhichgiveshigherpriority
queuesabsolutepreferentialtreatmentoverlowpriorityqueues.Thisensures
thetransmit
portdoesnotserveatransmitqueueunlessallhigherpriorityqueuesareempty.Asdescribed
previouslyinthissection,eightprioritydesignationsand,dependingonporttype,upto16
fourtransmitqueues aredefinedforeachport.
• Inboundratelimiting(IRL)— Noinboundratelimitersare
configured.
Youcanaddtothesedefaultconfigurationsbydefiningnewportgroupings,andassigning
inboundratelimitersortransmitqueuesandpriorities.WhetheryouarespecifyingIRLorTXQ
parameters,theprocessforuser‐definedCoSconfigurationinvolvesthefollowingstepsand
associatedcommandslistedinTable 8‐4.
Note: It is recommended that you use Enterasys NetSight Policy Manager as an alternative to CLI
for configuring policy-based CoS on the Enterasys Matrix Series devices.
Table 8-4 Configuring User-Defined CoS
To do this.... Use these commands...
Enable CoS. set cos state
If desired, create new or change existing CoS port configurations. set cos port-config irl
set cos port config txq