12
7.3.1.3. VRRP Accept Mode ..................................................................................................................................... 187
7.3.1.4. VRRP Route and Interface Tracking ............................................................................................................ 187
7.3.2. VRRP Configuration Example .......................................................................................................................... 187
7.3.2.1. VRRP with Load Sharing ............................................................................................................................. 188
7.3.2.2. VRRP with Route and Interface Tracking .................................................................................................... 190
7.4. IP Helper 193
7.4.1. Relay Agent Configuration Example ............................................................................................................... 195
7.5. Border Gateway Patrol (BGP) .............................................................................................. 197
7.5.1. BGP Topology ................................................................................................................................................. 197
7.5.1.1. External BGP Peering .................................................................................................................................. 198
7.5.1.2. Internal BGP Peering .................................................................................................................................. 198
7.5.1.3. Advertising Network Layer Reachability Information ................................................................................. 198
7.5.2. BGP Behavior .................................................................................................................................................. 199
7.5.2.1. BGP Route Selection ................................................................................................................................... 199
7.5.3. BGP Configuration Example ............................................................................................................................ 200
7.5.3.1. Configuring BGP on Router 9 ...................................................................................................................... 200
7.5.3.2. Configuring BGP on Router 3 ...................................................................................................................... 203
7.6. IPv6 Routing ......................................................................................................................... 204
7.6.1. How Does IPv6 Compare with IPv6 ................................................................................................................. 205
7.6.2. How are IPv6 Interface Configured ................................................................................................................. 205
7.6.3. Default IPv6 Routing Values ........................................................................................................................... 206
7.6.4. Configuring IPv6 Routing Features ................................................................................................................. 206
7.6.4.1. Configuring Global IP Routing Settings ....................................................................................................... 207
7.6.4.2. Configuring IPv6 Interface Settings ............................................................................................................ 207
7.6.4.3. Configuring IPv6 Neighbor Discovery ......................................................................................................... 208
7.6.4.4. Configuring IPv6 Route Table Entries and Route Preferences .................................................................... 210
7.6.4.5. IPv6 Show Commands ................................................................................................................................ 210
7.7. ECMP Hash Selection ........................................................................................................... 211
7.8. Bidirectional Forwarding Detection ..................................................................................... 211
7.8.1. Configuring BFD .............................................................................................................................................. 212
7.9. VRF Lite Operation and Configuration ................................................................................. 213
7.9.1. Route Leaking ................................................................................................................................................. 213
7.9.2. Adding Leaked Routes .................................................................................................................................... 214
7.9.3. Using Leaked Routes ....................................................................................................................................... 214
7.9.4. CPU-Originated Traffic.................................................................................................................................... 214
7.9.5. VRF Features Support ..................................................................................................................................... 214