Specifications

2
Software Architecture
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AsshowninFigure 5,theHPIclientlibrary(HCL)isadynamicallylinkedlibrary(DLL)that
providestheHPIAPIaswellasanintegratedRMCPclientforremoteHPIclient‐server
communication.TheHCLsourcecodeisindependentoftheoperatingsystemand
managementprocessor,andworkswithany
genericHPI‐compliantapplication.TheHCLLinux 
libraryisinstalledontheShelfManagermodule.TheHCLsourcecodeisavailableinthe
Radisyssoftwaredistribution.
AnSNMPagentisintegratedwiththeHCLinordertoprovideHPIservicestoanSNMP
managementapplication.ToenabletheHPIsubagent,seeEnablingtheHPIsubagenton
page 61.ForthespecificSNMPobjectstouse,seeChapter4,ChangingShelfSettingsUsing
HPI,onpage 53.
TheHPIclientlibrarycommunicateswiththeHPIserverthrougharemotesocketinterface
(seeFigure 6).TheHCLencapsulatesHPIrequestmessagesintoRMCPpackets,whichare
deliveredoverUserDatagramProtocol(UDP).TheHPIserverisresidentontheShelfManager
andacceptsremotecommandsreceivedattheRMCPserverport,623.
Figure 6. HPI implementation
ShMC
ShMS
HPI Server
HPI Server
Socket I/F
HPI Client
Socket I/F
HPI API
Application
Command
Socket
Event
Socket
HPI
Session