6.3

Table Of Contents
VMware, Inc. 79
Chapter 10 Troubleshooting
Symptom
ApplicationsoperatenormallywhenthePrimaryserverisactivebutoperateslowlywhentheSecondary
serverisactive(orthereverse).
Cause
AlargediscrepancyoccursintheprocessingpowerbetweenthePrimaryandSecondaryservers.Oneserver
canhandletheoperationalloadwhiletheothercannot.Theloadonaserverisgreaterwhileintheactiverole
whentheprotectedapplicationstarts.Applicationsontheserverpairrunsuccessfullywhenthe
Primary
serverisactive,butexperienceperformanceissueswhentheSecondaryisactive(orthereverse).Problemscan
ariseevenwhenthemorepowerfulserverisactive.
Resolution
Bothserversmusthaveapproximatelyequivalentprocessingpower,RAManddiskperformance.Upgrade
thehardwareononeserverinthepairsothatthetwoservershaveroughlythesameperformance.
Scheduled Resource Intensive Tasks
Schedulingmultipleresourceintensivetasksatthesametimecanadverselyimpactserverperformanceand
affectapplicationperformance.
Symptom
Resourceintensescheduledtasksimpactperformanceatcertaintimes.
Cause
Twoormoreresourceintenseprocessesrunsimultaneouslyoroneprocessperformsactionsthatincreasethe
loadonvCenterServerHeartbeatbytriggeringadditionalandsometimesunnecessaryreplicationtraffic.
Examples:processessuchasbackups,databasemaintenancetasks,diskdefragmentation,orscheduledvirus
scans.
Resolution
Scheduleoperationssothattheydonotoverlapandschedulethemoutsideregularworkinghours,when
fewerusersareaccessingtheprotectedapplicationandconsequentlylessloadontheserver.