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Table Of Contents
Lab Manager User’s Guide
230 VMware, Inc.
Fromaperformanceperspective,networkfencingimpactsthetrafficflowbetween
modules.Fencingrequiresaslightlyhighernumberofresourcesonthehost,suchas
memory,CPU,andnetworking.Ifyouenablefencingbutneveruseit,theseresources
arenotconsumed.
Understanding Fencing
Virtualmachinesinaconfigurationhavepreconfigured(internal)IPaddresses.When
youdeployvirtualmachinesinfencedmode,Lab Managerassignsauniqueexternal
IPaddresstoeachofthesemachines.Throughtheseexternaladdresses,virtual
machinesbothinsideandoutsidethefencecancommunicatewitheachother.
Lab Managerusesavirtual
machinecalledavirtualroutertoroutepacketsbetween
thesevirtualmachines.Lab Managerconfiguresthevirtualrouterwhenyoudeploya
fencedconfigurationanddeletesitwhenyouundeploytheconfiguration.
Figure D1illustratesconfigurationswithoutfencingandwithfencing.
Figure D-1. Configuration A (Without Fencing) and Configuration B (With Fencing)
N
OTEWhenyoudeployaconfigurationinfencedmodewiththeBlockInandOut
option,Lab ManagerdoesnotcreateavirtualrouterorassignexternalIPaddresses.
See“FencingOptions”onpage 231.
fenced
network
ESX Server host 2ESX Server host 1
client machine
configuration a configuration b
(fenced)
physical network
legend
connection
fenced connection
IIP internal IP address
EIP external IP address for fenced configurations
VR virtual router
EIP 192.168.0.4 EIP 192.168.0.3
IIP 192.168.0.1
MAC 00:50:56:00:00:01
IIP 192.168.0.2
MAC 00:50:56:00:00:02
VM1 VM2
IIP 192.168.0.1
MAC 00:50:56:00:00:01
IIP 192.168.0.2
MAC 00:50:56:00:00:02
VM1 VM2
VR