Users Guide

Table Of Contents
Border Gateway Protocol............................................................................................................................................. 780
Sessions and peers.................................................................................................................................................... 781
Martian addresses......................................................................................................................................................781
Route reflectors.........................................................................................................................................................782
Multiprotocol BGP.....................................................................................................................................................782
Attributes.................................................................................................................................................................... 783
Disable announcement of ASN values..................................................................................................................783
Selection criteria........................................................................................................................................................783
Weight and local preference...................................................................................................................................784
Multiexit discriminators............................................................................................................................................784
Origin............................................................................................................................................................................785
AS path and next-hop.............................................................................................................................................. 785
Best path selection................................................................................................................................................... 786
More path support.................................................................................................................................................... 786
Advertise cost............................................................................................................................................................ 787
4-Byte AS numbers...................................................................................................................................................787
AS number migration................................................................................................................................................ 787
Graceful restart......................................................................................................................................................... 788
Configure Border Gateway Protocol.................................................................................................................... 788
Enable BGP.................................................................................................................................................................789
BGP over unnumbered interfaces..........................................................................................................................791
Auto-unnumbered interfaces for BGP................................................................................................................. 793
Configure Dual Stack................................................................................................................................................797
Configure administrative distance.........................................................................................................................797
Peer templates...........................................................................................................................................................798
Neighbor fall-over..................................................................................................................................................... 802
Configure password................................................................................................................................................. 803
Fast external fallover............................................................................................................................................... 805
Passive peering..........................................................................................................................................................806
Local AS.......................................................................................................................................................................807
AS number limit......................................................................................................................................................... 808
Redistribute routes................................................................................................................................................... 809
Additional paths..........................................................................................................................................................810
MED attributes........................................................................................................................................................... 810
Local preference attribute........................................................................................................................................811
Weight attribute.........................................................................................................................................................812
Enable multipath.........................................................................................................................................................812
Route-map filters.......................................................................................................................................................813
Route reflector clusters........................................................................................................................................... 813
Aggregate routes....................................................................................................................................................... 814
Confederations...........................................................................................................................................................815
Route dampening.......................................................................................................................................................815
Timers........................................................................................................................................................................... 817
Neighbor soft-reconfiguration................................................................................................................................ 817
Redistribute iBGP route to OSPF.......................................................................................................................... 818
View BGP routes information................................................................................................................................. 819
Debug BGP..................................................................................................................................................................819
Configuring BGP template.......................................................................................................................................819
Example - BGP in a VLT topology.........................................................................................................................820
Example - Three-tier CLOS topology with eBGP..............................................................................................825
Contents
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