Specifications

2
Software Architecture
26
Figure 7. SCM Shelf Manager redundancy
Shelf Manager failover
ComponentfailuresintheShMSandShMCaredetectedthroughthefollowingcombination
ofsendinganechorequestpacketthenwaitingforavalidresponse(pinging)andmonitoring
theperiodicwatchdogstrobes:
1. EachShMCpingsitspeerShMCovertheIPMB.
2. EachShMSattemptstopingitspeerShMSovertheLAN
interfaceonthebackplane.
3. IfpingsovertheLANinterfacefail,theShMStriestopingitspeerShMSusingthefailover
paththroughIPMBandtheserialinterfaces,asindicated inFigure 7.
SCM
SCM
ShMS
ShMS
ShMC
ShMC
IPMB-0 A interface
IPMB-0 B interface
Serial
interface
Serial
interface
ShMS/ShMC Synchronization Normal Path
ShMS Synchronization Failover Path
IPMB inter face
LAN interface
LAN interface