Specifications

Basic System Administration
234 VMware, Inc.
MigrationwithVMotionhappensinthreestages:
1WhenthemigrationwithVMotionisrequested,VirtualCenterverifiesthatthe
existingvirtualmachineisinastablestatewithitscurrenthost.
2Thevirtualmachinestateinformation(thatis,memory,registers,andnetwork
connections)iscopiedtothetargethost.
3Thevirtualmachineresumes
itsactivitiesonthenewhost.
Ifanyerroroccursduringmigration,thevirtualmachinesreverttotheiroriginalstates
andlocations.
VMotion Requirements
TobeconfiguredforVMotion,eachhostintheclustermustmeetthefollowing
requirements.
Shared Storage
Ensurethatthemanagedhostsusesharedstorage.Sharedstorageistypicallyona
storageareanetwork(SAN),butcanalsobeimplementedusingiSCSIandNASshared
storage.SeetheVMwareSANConfigurationGuideforadditionalinformationonSAN
andtheESXServer3ConfigurationGuideorESXServer3i
ConfigurationGuidefor
informationonothersharedstorage.
Shared VMFS Volume or NAS Storage
ConfigureallmanagedhoststousesharedVMFSvolumesortobelocatedonNAS
storage.IfusingsharedVMFSvolumes:
 PlacethedisksofallvirtualmachinesonVMFSvolumesthatareaccessiblebyboth
sourceandtargethosts.
 EnsurethattheVMFSvolumeissufficientlylargetostoreallvirtualdisksforyour
virtualmachines.
CPU Compatibility
Makesurethatthesourceanddestinationhostshaveacompatiblesetofprocessors.
VMotiontransferstherunningarchitecturalstateofavirtualmachinebetween
underlyingVMwareESXServersystems.VMotioncompatibilityrequiresthatthe
processorsofthetargethostbeabletoresumeexecutionusingtheequivalent
instructionsthatthe
processorsofthesourcehostwereusingwhensuspended.
Processorclockspeedsandcachesizes,andthenumberofprocessorcorescanvary,but