Multicast and Routing Guide K/KA/KB.15.15

Owner router..................................................................................................................277
Backup router..................................................................................................................278
VR priority operation...................................................................................................278
Preempt mode............................................................................................................278
Virtual router MAC address...............................................................................................278
VRRP and ARP for IPv4.....................................................................................................278
VRRP and neighbor discovery for IPv6................................................................................278
Duplicate address detection (DAD).....................................................................................279
General operating rules....................................................................................................279
Steps for provisioning VRRP operation.....................................................................................280
Basic configuration process...............................................................................................280
Example configuration......................................................................................................281
Associating more than one VIP with a VR............................................................................283
Dynamically changing the priority of the VR.............................................................................284
Failover operation.................................................................................................................284
Pinging the virtual IP of a backup router...................................................................................285
Using the Pre-empt Delay Timer (PDT)......................................................................................285
When OSPF is also enabled on the VRRP routers.................................................................285
Configuring the PDT.........................................................................................................285
VRRP preempt mode with LACP and older HP devices......................................................285
What occurs at startup.................................................................................................285
Selecting a value for the PDT........................................................................................286
Possible configuration scenarios.........................................................................................286
PDT=zero seconds.......................................................................................................286
PDT is greater than or equal to the master down time (3 times the advertisement interval)......286
PDT is less than the master down time............................................................................286
When the PDT is not applicable.........................................................................................286
Standards compliance...........................................................................................................287
Operating notes...................................................................................................................287
Dynamic priority change operating notes............................................................................288
Error messages—Track interface.............................................................................................288
13 Border Gateway Protocol (BGP)..............................................................289
Introduction..........................................................................................................................289
Configuring BGP globally......................................................................................................289
Configuring a BGP routing process.....................................................................................290
Configuring a fixed router ID for local BGP routing process...................................................290
Specifying the networks to be advertised by the BGP routing process......................................290
Adjusting BGP network timers............................................................................................290
Re-enabling state contained within nodes of BGP processes...................................................291
Configuring BGP policy globally.............................................................................................291
Delaying sending the BGP open message...........................................................................292
Specifying the maximum routes that BGP will accept for installation into the RIB.......................292
Enabling comparison of MED for paths from neighbors in different autonomous systems............292
Specifying the number of times an AS number can appear in AS_PATH..................................293
Configuring BGP to not consider AS_PATH..........................................................................293
Breaking ties between routes based on originator ID value....................................................293
Comparing identical routes received from different external peers...........................................293
Assigning value of infinity to routes missing MED attribute.....................................................294
Setting BGP MED on routes when advertised to peers...........................................................294
Specifying a route's preference..........................................................................................294
Enabling client-to-client route reflection................................................................................294
Specifying cluster ID when BGP router is route-reflector.........................................................294
BGP graceful restart..............................................................................................................295
Configuring BGP graceful restart timers...............................................................................295
12 Contents