Enterasys SecureStack C2 C2G170-24

SecureStack C2 Configuration Guide 12-1
12
Port Priority and Rate Limiting Configuration
ThischapterdescribesthePortPriorityandRateLimitingsetofcommandsandhowtousethem.
Port Priority Configuration Summary
TheSecureStackC2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 through 7)andassignthemtotransmitqueuesforeach
port.
Apriority0through7canbesetoneachport,with0being
thelowestpriority.Aportreceivinga
framewithoutpriorityinformationinitstagheaderisassignedapriorityaccordingtothedefault
prioritysettingontheport.Forexample,ifthepriorityofaportissetto4,theframesreceived
throughthatportwithoutapriorityindicated
intheirtagheaderareclassifiedasapriority4and
transmittedaccordingtothatpriority.Inaddition,thedevice’sratelimitingcapabilitiesallowyou
tofurtherprioritizetrafficbyli mitingtherateofinboundtrafficonaperport/prioritybasis.
Configuring Port Priority
Purpose
Tovieworconfigureportprioritycharacteristicsasfollows:
•DisplayorchangetheportdefaultClass‐ofService(CoS)transmitpriority(0through7)of
eachportforframesthatarereceived(ingress)withoutpriorityinformationintheirtag
header.
For information about... Refer to page...
Port Priority Configuration Summary 12-1
Configuring Port Priority 12-1
Configuring Priority to Transmit Queue Mapping 12-4
Configuring Quality of Service (QoS) 12-6
Configuring Port Traffic Rate Limiting 12-10
Note: When CoS override is enabled using the set policy profile command as described in “set
policy profile” on page 11-3, CoS-based classification rules will take precedence over priority
settings configured with the set port priority command described in this section.