PoE Port Status LEDs
C-2 About PoE (Power over Ethernet)
PoE Port Status LEDs
ThePoEportstatusofeach10/100/1000 MbpsRJ45portisindicatedbythetwo‐colorRXandTX
LEDdisplayforeachport.ToobservethePoEportstatusindications,youmustswitchtheSSA
fromthedefaultRX/TXstatusmodetothePoEPortstatusmodeusingthe
redPoEbutton.The
switchoperationandades criptionofhowtousetheLEDindicationsaredescribedin“Port
LEDs”onpage 3‐1.
Allocation of PoE Power to Devices
TheS‐SeriesfirmwaredeterminesthepoweravailableintheSSAforPoEbasedonpowersupply
statusandpowersupplyredundancymode.Thesystemcalculatesandreservesthecorrect
amountofpowerrequiredbytheSSAandthenmakesthebalanceofpoweravailableforPoE.
Whenanychangeis
madetothepowersupplystatusorredundancymode,thefirmware
recalculatesthepoweravailableforPoE.
ThepoweravailableforPoEisdistributedbasedontheconfiguredallocationmode:
• Automaticmode(default),inwhichavailablepowerisdistributedev enly.Anychangein
availablepower,duetoachangeinpower
supplystatusorredundancymode,willtriggeran
automaticredistributionofpower.
• Manualmode,inwhichthepowerbudgetismanuallyconfigured,usingeitherCLI
commandsortheMIBs.Thewattageconfiguredcannotexceedthetotalpoweravailableon
theswitchforPoE.
Theconfiguredwattageassignmentisusedto
calculatethetotalavailablePoEpower.Ifthe
totalavailablePoEpowerchanges,aredistributionofavailablepowerwilloccur,applyingthe
calculatedpercentage.
IfthePoEpowerneededorrequestedexceedsthepoweravailable,thesystemwillgeneratean
SNMPtraptonotifythesystemmanager.
Formoreinformationonconfiguring
allocationmode,seetheEnterasysS‐SeriesCLIReference
Guide.
Power Distribution Upon Power Supply Removal or Addition
Whenapowersupplyisremoved,theSSArespondstothedecreaseinavailablepowerbydoing
thefollowing:
1. Detectingthepowersupplyremovalandrecalculatingavailablepower.
2. Subtractingthepowercapacityforitsbasesystemfromavailablepower.
3. DistributingremainingpowerequallyforPoE.
4. DroppingsupporttoPoEdevicesasnecessaryto
staywithintheprogrammedmaximum
power.
Whenapowersupplyisadded,theSSArespondstotheincreaseinavailablepowerbydoingthe
following:
1. Detectingthepowersupplyadditionandrecalculatingavailablepower.
2. Subtractingthepowercapacityforitsbasesystemfromavailablepower.
3. DistributingremainingpowerequallyforPoE.