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Software Architecture

HPI server redundancy

TheRadisy sHPIserverusesaredundancymodelverysimilartotheactive‐standbymodel

usedbytheShelfManager.SincetheHPIserveriscombinedwiththeShelfManagerServer

(ShMS)daemon,itsharesthesameredundancystatuswiththeShelfManager.Theactive

ShelfManagerhoststheactiveHPIserverwhilethestandbyShelfManagerhoststhestandby

HPIserver.Atanypoint oftimeafterHPIserverinitializationiscomplete,thestandbyHPI

serverisfullyredundantwiththeactiveHPIserverandiscapableofassumingtheactiverole

immediatelyfollowingafailover.

TheactiveHPIserverfullycomplieswiththeSAFHPISpecification.Thefullyredundant

standbyHPIservercannotperformcertainactions,suchashot‐swaphandlingandfailovers

duetoplatformandimplementationrestrictionsplacedonthestandbyrole.Althoughitis

possibletoopensessionsonthestandbyHPIserverfornormaloperation,HPIsessionsshould

beopenedonlyontheactiveHPIserverusingthededicated ShelfManagerIPaddressas

DomainId.SeeWritingHPIapplicationsonpage 57forinformationonhowtoopenHPI

sessions.

ThefollowingtypesofHPIdataareactivelysynchronizedwiththepeerHPIservers.

•Sessions–SessionsopenedontheactiveHPIserverpersistoverfailoverstothestandby

ShelfManagerandHPIserver.HPIapplicationscanusethesameSessionIdtoex ecuteHPI

operationsonthesystemfollowingafailover.HPIapplicationsthatopenedthesession

usingthededicatedShelfManagerIPaddressasDomainIdwillnotexperienceany

noticeabledifferenceinHPIserveroperationfollowingafailover,otherthanpossiblya

smalldelayinthenextHPIcommandissuedfollowingthefailover.

•Eventsubscriptions–Sessioneventsubscriptionspersistoverfailovers.Ifanevent

subscriptionwasopenedonasession,itremainsineffectfollowingafailover.Session

eventqueuesarealsosynchronized,ensuringthatnoeventsarelostfromasessionevent

queuethathassubscriptionenabledduetoafailover.

•Domaintag,resourcetag,andresourceseverity–Alluserchangestothedomaintag,

resourcetags,orresourceseveritiesar esynchronizedtothepeerHPI

serverandpersist

followingafailover.

•Eventsandeventlogs–Allevents,bothsystemgeneratedanduseradded,are

synchronizedtothestandbyHPIserver.TheHPIdomainandresourceeventlogsinthe

activeandstandbyHPIserversarethuskeptinsync.Userchangestoeventlogtimesand

eventlogstatesarealsosynchronized.

•Alarms–Allalarms,bothsystemgeneratedanduseradded,aresynchronizedtothepeer

HPIserver.ThedomainalarmtablesintheactiveandstandbyHPIserversarethuskeptin

sync.Userinitiatedchanges,suchasalarmacknowledgementsanduseralarmdeletions,

arealsosynchronized.

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RadiSys ATCA-4616 Specifiche Pagina 31