Specifications

2
Software Architecture
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Inenhancedmode,theShelfManagerusesthe/etc/shmgr.conffile.TheShelfManagerdoes
notneedtousetheshmgr_basic.conffileprovidedforbasicmode;itcandiscoverand
manageanytypeofATCAnodemodule.Thersys‐ipmitoolutilityisalsoavailablefor
performingoperationsatthecommandshell
andinscripts.
Software redundancy
ThefollowingsectionsapplyonlytoshelveswhereanSCMisactingastheShelfManager.
TheydonotapplytoATCA‐6002shelves.
Shelf Manager redundancy
TheShelfManageroperatesinafullyredundantactive‐standbymodelwhenbothSCMsare
installed.Duringsystemstartup,ifredundantShelfManagersaredetected,anarbitration
mechanismbetweenthepeerShMCsdecideswhichonetakesoverasactivewhiletheother
assumesthestandbyrole.OncearbitrationiscompleteandtheactiveShelfManageris
initialized,theActiveLEDontheactiveShelfManagerglowssolidamber.TheactiveShelf
Managerisresponsibleformonitoringandmanagingtheshelf.Allconfigurationchangesand
eventdataaresynchronizedwiththestandbyShelfManagersothatitisreadytoassumethe
activeroleatanypointoftime.
OnasingleSCM,theShMSrunningontheLMPandtheShMCcommunicatewitheachother
overaseriallinkusingtheOpenIPMIserialdriverinBasicmode.ThetwoShMCsfromthe
SCMpaircommunicateovertheIPMB,whichisphysicallyredundant.Additionally,thetwo
ShMSsfromtheSCMpairsynchronizeoveranEthernetLANinterfaceonthebackplane.