6.3

Table Of Contents
VMware, Inc. 19
Chapter 1 Introduction
Thisenablesthepublicidentityoftheserver.Theactiveandpassiveserversbothusethesamesystem
nameandsamePrincipal(Public)IPaddress.ThisPrincipal(Public)IPaddresscanbeenabledonlyon
onesystematanytime.Whenthepublicidentityisenabled,anyclientspreviouslyconnectedtothe
server
beforetheautomaticfailoverareabletoreconnect.
3Startinterceptingupdatestoprotecteddata.Anyupdatestotheprotecteddataaresavedinthesend
queueonthelocalserver.
4Startallprotectedapplications.Theapplicationsusethereplicatedapplicationdatatorecover,andthen
acceptreconnectionsfromany
clients.Anyupdatesthattheapplicationsmaketotheprotecteddataare
interceptedandlogged.
Atthispoint,theoriginallyactiveserverisofflineandtheoriginallypassiveserverisfillingtheactiverole
andisrunningtheprotectedapplications.Anyupdatesthatcompletedbeforethefailoverareretained.
Applicationclients
canreconnecttotheapplicationandcontinuerunningasbefore.
Managed Failover
Managedfailoverissimilartoautomaticfailoverinthatthepassiveserverautomaticallydeterminesthatthe
activeserverhasfailedandcanwarnthesystemadministratoraboutthefailure;butnofailoveractuallyoccurs
untilthesystemadministratormanuallytriggersthisoperation.
Automatic Switchover and Failover in a WAN Environment
AutomaticswitchoverandfailoverinaWANenvironmentdifferfromaautomaticswitchoverandfailoverin
aLANenvironmentduetothenatureoftheWANconnection.InaWANenvironment,automaticswitchover
andfailoveraredisabledbydefaultintheeventthattheWANconnectionislost.
Shouldacondition
arisethatwouldnormallytriggeranautomaticswitchoverorfailover,theadministrator
willreceivevCenterServerHeartbeatalerts.TheadministratormustmanuallyclicktheMakeActivebutton
ontheServer:SummarypageofthevCenterServerHeartbeatConsoletoallowtherolesoftheserversto
switchovertheWAN.
To enable Automatic Switchover in a WAN
1In
thevCenterServerHeartbeatConsole,clicktheNetworktabtodisplaytheNetworkMonitoringpage.
2ClickConfigureAutoswitchover.
3 SelecttheAutoswitchoverifclientnetworkconnectivitylostforcheckbox.
4Configurethenumberofpingstowaitbeforeperformingtheautoswitchover.
5ClickOK.
Recovery from a Failover
AssumingthatthePrimaryserverwasactiveandtheSecondaryserverwaspassivebeforethefailover,after
thefailovertheSecondaryserverisactiveandthePrimaryserverispassive.
Afterrectifyingtheproblemthatinitiatedthefailover,itisasimpleprocesstoreinstatethePrimaryserveras
theactive
serverandtheSecondaryserverasthepassiveserver.
WhenvCenterServerHeartbeatstartsonthefailedPrimaryserver,itdetectsthatitdidnotstopcleanlythe
previoustime.ItdisablesthepublicidentitybydeployingtheIPpacketfilterandhaltsvCenterServer
Heartbeatsothattheissuesthat
causedthefailurecanberesolved.
N
OTEWhenfailoverconditionssuchasapowerfailurecausebothactiveandpassiveserverstofail,the
conditionmayresultthatcausesbothserverstorestartinpassivemode.Inthissituation,manualintervention
isrequired.