3Com S7906E Configuration Manual page 768

1 BGP Configuration ····································································································································1-1
BGP Overview·········································································································································1-1
Formats of BGP Messages ·············································································································1-2
BGP Path Attributes ························································································································1-4
BGP Route Selection·······················································································································1-8
iBGP and IGP Synchronization ·····································································································1-11
Settlements for Problems in Large Scale BGP Networks ·····························································1-11
BGP GR·········································································································································1-14
MP-BGP ········································································································································1-15
Protocols and Standards ···············································································································1-16
BGP Configuration Task List·················································································································1-16
Configuring BGP Basic Functions·········································································································1-18
Prerequisites··································································································································1-18
Creating a BGP Connection ··········································································································1-18
Specifying the Source Interface for TCP Connections··································································1-19
Allowing Establishment of eBGP Connection to a Non Directly Connected Peer/Peer Group·····1-19
Controlling Route Generation ···············································································································1-20
Prerequisites··································································································································1-20
Injecting a Local Network ··············································································································1-20
Configuring BGP Route Redistribution··························································································1-20
Enabling Default Route Redistribution into BGP···········································································1-21
Controlling Route Distribution and Reception·······················································································1-21
Prerequisites··································································································································1-21
Configuring BGP Route Summarization························································································1-21
Advertising a Default Route to a Peer or Peer Group ···································································1-22
Configuring BGP Route Distribution/Reception Filtering Policies ·················································1-22
Enabling BGP and IGP Route Synchronization ············································································1-24
Limiting Prefixes Received from a Peer/Peer Group ····································································1-24
Configuring BGP Route Dampening ·····························································································1-25
Configuring a Shortcut Route ········································································································1-25
Configuring BGP Route Attributes ········································································································1-26
Prerequisites··································································································································1-26
Specifying a Preferred Value for Routes Received·······································································1-26
Configuring Preferences for BGP Routes ·····················································································1-26
Configure the Default Local Preference ························································································1-27
Configuring the MED Attribute·······································································································1-27
Configuring the Next Hop Attribute································································································1-29
Configuring the AS-PATH Attribute ·······························································································1-30
Tuning and Optimizing BGP Networks ·································································································1-32
Prerequisites··································································································································1-32
Configuring BGP Keepalive Interval and Holdtime ·······································································1-32
Configuring the Interval for Sending the Same Update·································································1-33
Configuring BGP Soft-Reset ·········································································································1-33
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