iv
BGP route selection ············································································································································· 124
BGP and IGP synchronization···························································································································· 125
Settlements for problems in large scale BGP networks ··················································································· 126
BGP GR ································································································································································ 129
MP-BGP································································································································································· 130
Protocols and standards ····································································································································· 130
BGP configuration task list ·········································································································································· 131
Configuring BGP basic functions································································································································ 132
Configuration prerequisites ································································································································ 132
Creating a BGP connection································································································································ 132
Specifying the source interface for TCP connections ······················································································· 133
Allowing establishment of EBGP connection to an indirectly connected peer or peer group····················· 134
Controlling route generation ······································································································································· 134
Configuration prerequisites ································································································································ 134
Injecting a local network ···································································································································· 134
Configuring BGP route redistribution ················································································································ 135
Enabling default route redistribution into BGP ································································································· 135
Controlling route distribution and reception ············································································································· 136
Configuration prerequisites ································································································································ 136
Configuring BGP route summarization ············································································································· 136
Advertising a default route to a peer or peer group ······················································································· 136
Configuring BGP route distribution/reception filtering policies ····································································· 137
Enabling BGP and IGP route synchronization ································································································· 139
Limiting prefixes received from a peer or peer group····················································································· 139
Configuring BGP route dampening ··················································································································· 140
Configuring a shortcut route······························································································································· 140
Configuring BGP route attributes································································································································ 141
Configuration prerequisites ································································································································ 141
Specifying a preferred value for routes received····························································································· 141
Configuring preferences for BGP routes ··········································································································· 141
Configuring the default local preference ·········································································································· 142
Configuring the MED attribute ··························································································································· 142
Configuring the NEXT_HOP attribute ················································································································ 144
Configuring the AS_PATH attribute ··················································································································· 145
Tuning and optimizing BGP networks························································································································ 147
Configuration prerequisites ································································································································ 147
Configuring the BGP keepalive interval and holdtime ···················································································· 147
Configuring the interval for sending the same update ···················································································· 148
Configuring BGP soft-reset·································································································································· 148
Enabling the BGP ORF capability······················································································································ 149
Enabling 4-byte AS number suppression ·········································································································· 150
Setting the DSCP value for BGP packets··········································································································· 151
Enabling quick EBGP session reestablishment ································································································· 151
Enabling MD5 authentication for TCP connections ························································································· 152
Configuring BGP load balancing ······················································································································ 152
Forbiding session establishment with a peer or peer group··········································································· 152
Configuring a large scale BGP network ···················································································································· 153
Configuration prerequisites ································································································································ 153
Configuring BGP peer groups ··························································································································· 153
Configuring BGP community ······························································································································ 155
Configuring a BGP route reflector ····················································································································· 155
Configuring a BGP confederation ····················································································································· 156
Configuring BGP GR ··················································································································································· 157
Enabling trap ································································································································································ 157