Dell PowerSwitch S4128F-ON OS10 Enterprise Edition User Guide Release 10.4.1.0 - Page 286
BFD for BGP, BFD for BGP example
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• multiplier number - Enter the number of consecutive packets that must not be received from a BFD peer before the session state changes to Down, from 3 to 50; default 3. • role {active | passive} - Enter active if the router initiates BFD sessions. Both BFD peers can be active at the same time. Enter passive if the router does not initiate BFD sessions, and only responds to a request from an active BFD to initialize a session. The default is active. 2 Enable BFD globally in CONFIGURATION mode. bfd enable To verify that BFD is globally enabled, enter the show running-config bfd command. BFD global configuration OS10(config)# bfd interval 250 min_rx 300 multiplier 4 role passive OS10(config)# bfd enable OS10(config)# do show running-config bfd ! bfd enable bfd interval 250 min_rx 300 multiplier 4 role passive BFD for BGP In a BGP core network, BFD enables faster network reconvergence. BFD rapidly detects communication failures in BGP fast-forwarding paths between internal BGP (iBGP) and external BGP (eBGP) peers. BFD for BGP is supported on physical, port-channel, and VLAN interfaces. BFD for BGP does not support the BGP multihop feature. Before configuring BFD for BGP, first configure BGP on the interconnected routers. For more information, see Border Gateway Protocol. BFD for BGP example In this BFD for BGP configuration example, Router 1 and Router 2 use eBGP in a transit network to interconnect AS1 and AS2. The eBGP routers exchange information with each other and with iBGP routers to maintain connectivity and accessibility within each autonomous system. When you configure a BFD session with a BGP neighbor, you can: • Establish a BFD session with a specified BGP neighbor using the neighbor ip-address and bfd commands. 286 Layer 3
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