Enterasys RoamAbout RBT-4102 - Page 88

WDS and STP
4-52 Advanced Configuration
– BridgeMaxAgeisthemaximumtime(inseconds)adevicecanwaitwithoutreceivinga
configurationmessagebeforeattemptingtoreconfigure.Alldeviceports(exceptfor
designatedports)shouldreceiveconfigurationmessagesatregularintervals.Anyport
thatagesoutSTPinformation(providedinthelastconfigurationmessage)becomes
the
designatedportfortheattachedLAN.Ifitisarootport,anewrootportisselectedfrom
amongthedeviceportsattachedtothenetwork.Range:6‐40seconds
‐ Default:20
‐ Minimum:Thehigherof6or[2x(HelloTime+1)].
‐ Maximum:Thelowerof40
or[2x(ForwardDelay‐1)]
– BridgeHelloTimeistheinterval(inseconds)atwhichtherootdevicetransmitsa
configurationmessage.Range:1‐10seconds
‐ Default:2
‐ Minimum:1
‐ Maximum:Thelowerof10or[(Max.MessageAge/2)‐1]
– BridgeForwardDelayisthemaximumtime
(inseconds)thisdevicewaitsbeforechanging
states(forexample,discardingtolearningtoforwarding).Thisdelayisrequiredbecause
everydevicemustreceiveinformationabouttopologychangesbeforeitstartstoforward
frames.Inaddition,eachportneedstimetolistenforconflictinginformationthatwould
makeitreturnto
adiscardingstate;otherwise,temporarydataloopsmightresult.Range:
4‐30seconds
‐ Default:15
‐ Minimum:Thehigherof4or[(Max.MessageAge/2)+1]
‐ Maximum:30
– LinkPathCostisusedbytheSTPtodeterminethebestpathbetweendevices.Therefore,
lowervaluesshouldbe
assignedtoportsattachedtofastermedia,andhighervalues
assignedtoportswithslowermedia.Pathcosttakesprecedenceoverportpriority.
‐ Range:1‐65535
‐ Default:Ethernetinterface:19;Wirelessinterface:40
– LinkPortPrioritydefinesthepriorityusedforthis portintheSpanningTreeProtocol.If
thepath
costforallportsonaswitcharethesame,theportwiththehighestpriority(for
example,lowestvalue)willbeconfiguredasanactivelinkinthespanningtree.This
makesaportwithhigherprioritylesslikelytobeblockediftheSpanningTreeProtocolis
detecting
networkloops.Wheremorethanoneportisassignedthehighestpriority,the
portwithlowestnumericidentifierwillbeenabled.
‐ Default:128
‐ Range:0‐255,instepsof16