Specifications

6
Troubleshooting
112
TherearenohardwarepresencedetectlinesinATCAbackplanes.TheShMSthusrelieson
messagebasedpings toperiodicallyqueryeachintelligentFRUwhosepresenceisknownto
theShMS,asfollows:
1. TotheIPMCofeveryintelligentFRUintheshelftheShMSsendsaGetDeviceIdpingevery
3secondsbydefault.Ifapingtimesoutwitha0xC3IPMIresponsecodetheShMS
schedulesasecondpingforthatIPMCafter2seconds.
2. Ifthesecond
GetDeviceIdpingalsofailsthentheShMSgeneratestheMx‐>M7eventfor
theFRUwherexisnot1,butitisthelastknowngoodhot‐swapstateoftheFRU. Thisis 
thecommunicationlosteventwhichismappedtoaResourceFailedconditioninHPI.You
willseetheResourceFailedalarmforthatFRU'sre sourcewhenthishappens.
3. Ifx(lastknowngoodhot‐swapstate)isM1thenaM7eventisnotgenerated.Inthiscase
theShMSwilldeemthattheFRUhasbeenextractedfromtheslotandwillgeneratean
M1‐>M0event.ThismapstoaINACTIVE‐>NOT_PRESENThot‐swapeventinHPIandthe
resourceforthatFRUwillberemovedfromtheHPIRPTafterthisevent.
4. FollowingtheM7event,theShMSkeepstryingtopingtheIPMC thathaslost
communicationevery3secondsanywaytocheckifcommunicationisregained.Iftheping
succeeds,theShMSgeneratesanM7‐>Mxeventwherexwasthelastknowgoodhot‐
swapstate.ItthenlaunchesarediscoveryofthatFRUtolearnthecurrentstateofthat
FRUbecauseitmayhaveundergonechangeswhilecommunicationwiththeShMSwas
lost.
ThereisaconfigurationparameteravailablefortheShelfManagerthatcanchangethe
ShMS'spresencepingintervalsfromthedefaultof3seconds.Thisparameteriscalled
SHMS_FRU_HEARTBEAT_FREQUENCYandcanbesetinthe/etc/shmgr.conffile.Youwillneed
toreboottheSCMorrestarttheShelfManageraftermakingthisupdate.Bydefaultthis
parameterissetto3secondsintheread‐only/usr/share/shmgr/shmgr.defsfilewhichhouses
alltheShelfManagerparameterswiththeirdefaults.
AbriefdescriptionoftheFRUheartbeatparameterfromthe/usr/share/shmgr/shmgr.defs
file:
#SetthedefaultFRUpresencepingfrequencyinseconds
#Thisisthefrequencyinwhichtheshelfmanagerwillping
#intelligentFRU‐sfortheirpresence.
#Minimumis2secs,Maximumis60seconds,Defaultis3secs.
InordertochangetheFRUheartbeatparameterintheshmgr.conffile,inserttheline:
SHMS_FRU_HEARTBEAT_FREQUENCY=<pingintervalinsecs>
Note:ThisisnotaFRU‐specificparameter.Thenewpingintervalisglobalandappliedtoall
intelligentFRUsintheshelf.Asideeff ectofincreasingthepingintervalwouldbethatrealM7
conditionsforFRUswouldgetdetectedlate r thantheyarenow(afterabout5seconds).
Also
onceaFRUisphysicallyextractedfromtheshelftheShelfManagerwouldtakelongerto
generatetheINACTIVE‐>NOT_PRESENTevent.