Enterasys Networks DFE-Gold Series Configuring Policy Class of Service (CoS)

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)

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specification,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.

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