Specifications

Port Mirroring
SecureStack B2 Configuration Guide 7-33
Port Mirroring
TheSecureStackB2deviceallowsyoutomirror(orredirect)thetrafficbeingswitchedonaport
forthepurposesofnetworktrafficanalysisandconnectionassurance.Whenportmirroring is
enabled,oneportbecomesa monitorportforanotherportwithinthedevice.
Mirroring Features
TheSecureStackB2devicesupportsthefollowingmirroringfeatures:
• Mirroringcanbeconfiguredinamany‐to‐oneconfigurationsothatonetarget(destination)
portcanmonitortrafficonupto8sourceports.Onlyonemirrordestinationportcanbe
configuredperstack,ifapplicable.
•Bothtransmitandreceivetrafficwill
bemirrored.
•Adestinationportwillonlyactasamirroringportwhenthesessionisoperationallyactive.
•Whenaportmirroriscreated,themirrordestinationportisremovedfromtheegresslistof
VLAN1afterareboot.
•MACaddresseswillbelearnedforpacketstaggedwiththemirrorVLAN
ID.Thiswill
preventtheabilitytosnooptrafficacrossmultiplehops.
Configuring SMON MIB Port Mirroring
Overview
SMONportmirroringsupportonEnterasysSecureStackB2,B3,C2andC3devicesallowsyouto
redirecttrafficonportsremotelyusingSMONMIBs.Thisisusefulfortroubleshootingorproblem
solvingwhennetworkmanagementthroughtheconsoleport,telnet,orSSHisnotfeasible.
Procedures
PerformthefollowingstepstoconfigureandmonitorportmirroringusingSMONMIBobjects.
Tocreateandenableaportm irroringinstance:
1. OpenaMIBbrowser,suchasNetsightMIBTools
2. IntheMIBdirectorytree,navigatetotheportCopyEntryfolderandexpandit.
3. SelecttheportCopyStatusMIB.
4. Enteradesiredsource
andtargetportintheInstancefieldusingtheformatsource.target.
Forexample,3.2wouldcreatearelationshipwheresourceportfe.1.3wouldbemirroredto
targetportfe.1.2.
Caution: Port mirroring configuration should be performed only by personnel who are
knowledgeable about the effects of port mirroring and its impact on network operation.
Caution: Traffic mirrored to a VLAN may contain control traffic. This may be interpreted by the
downstream neighbor as legal control frames. It is recommended that you disable any protocols
(such as Spanning Tree) on inter-switch connections that might be affected .
Note: In order to configure a port mirroring relationship, both source and destination interfaces must
be enabled and operational (up).