Front-End Connectivity Modes
Dell Compellent 99
Legacy Mode
Legacymodeprovidescontrollerredundancyforadual‐controllerStorageCenterby
connectingmultipleprimaryandreservedportstoeachFibreChannelorEthernetswitch.
Inlegacymode,eachprimaryportonacontrollerispairedwithacorrespondingreserved
portontheothercontroller.Duringnormalconditions,theprimaryports
processIOand
thereservedportsareinstandbymode.Ifacontrollerfails,theprimaryportsfailoverto
thecorrespondingreservedportsontheothercontroller.Thisapproachensuresthat
serversconnectedtotheswitchdonotloseconnectivityifoneofthecontrollersfails.For
optimalperformance,
theprimaryportsshouldbeevenlydistributedacrossboth
controllers.Whenpossible,front‐endconnectionsshouldbemadetoseparate controllerIO
cardstoimproveredundancy.
Fault Domains in Legacy Mode
EachpairofprimaryandreservedportsisgroupedintoafaultdomainintheStorage
Centersoftware.Thefaultdomaindetermineswhichportsareallowedtofailovertoeach
other.
Thefollowingrequirementsapplytofaultdomainsinlegacymodeonadual‐controller
StorageCenter:
Afaultdomainmustcontainaonetypeoftransportmedia(FCoriSCSI,butnotboth).
Afaultdomainmustcontainoneprimaryportandonereservedport.
Thereservedportmustbelocatedonadifferentcontrollerthantheprimaryport.
Requirements for Legacy Mode
ThefollowingrequirementsmustbemettoconfigureaStorageCenterinlegacymode.
See Also
FibreChannelZoningonpage 10 2
Note: Forasingle‐controllerStorageCenter,onlyonefaultdomainisrequiredfor
eachtransporttype(FCoriSCSI)becausetherearenoreservedports.
Requirement Description
Controllerfront‐end
ports
Eachcontrollermusthaveenoughfront‐endportstoconnecttwopathsto
eachFibreChannelorEthernetswitch.
Multipathing Ifmultipleactivepathsareavailabletoaserver,theservermustbe
configuredforMPIOtousemorethanonepathsimultaneously.
FibreChannelzoning FCswitchesmustbe
zonedtomeetthelegacymodezoningrequirements.