User`s guide

Monitoring VRRP
Matrix DFE Series and N-SA User’s Guide 9-17
VRRP Authentication Commands
Bydefault,noauthenticationofVRRPpacketsisperformedontheMatrixDFESeriesorN‐SA
device.Youcanspecifyacleartextoramessagedigest(MD5)passwordtobeusedtoauthenticate
VRRPexchangesonroutinginterfaces.
Usethefollowingcommandininterfaceconfigurationmodetoseta
cleartextauthentication
password:
ip vrrp authentication-key password
Passwordisatextstring1to8charactersinlength.
UsethefollowingcommandininterfaceconfigurationmodetosetanMD5authentication
password:
ip vrrp message-digest-key vrid md5 password
Passwordisatextstring1to16charactersinlength.
Monitoring VRRP
UsethefollowingcommandinglobalconfigurationmodetodisplayVRRProutinginformation:
show ip vrrp
Example
ThisexampleshowsthatRouter1isconfiguredonVLAN1,VRID1,asthemasterrouterof
VRID1andtheownerofIPaddress10.0.0.1.ItalsoshowsRouter1isconfiguredasthe
primarybackuprouterforVRIDs2and3:
VRRP Configuration Notes
Determining the Backup to Master Time Interval
Ifabackuprouterdoesn’treceiveakeep‐aliveadvertisementfromthecurrentmasterwithina
certainperiodoftime,itwilltransitiontothemasterstateandstartsendingadvertisementsto
itself.Theamountoftimethatabackuprouterwillwaitbeforeitbecomesthenewmasterisbased

onthefollowingequation:
Master‐down‐interval=(3*advertisement‐interval)+skew‐time
Theskew‐timedependsonthebackuprouter’sconfiguredpriority:
Skew‐time=((256‐Priority)/256)
Therefore,thehigherthepriority,the fasterabackuprouterwilldetectthatthemasterisdown.
Forexample:
•Defaultadvertisement
‐interval=1second
Matrix>Router1(config)#show ip vrrp
-----------VRRP CONFIGURATION-----------
Vlan Vrid State Owner AssocIpAddr
1 1 Master 1 10.0.0.1
1 2 Primary 0 10.0.0.2
1 3 Primary 0 10.0.0.3