3com S7906E Instruccion De Instalación

 

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Since a router can reside in only one AS, the router can run only one BGP process. 

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You need to create a peer group before configuring it.  

 

BGP uses TCP as the transport layer protocol. By default, BGP uses the output interface of the optimal 

router to a peer as the source interface for establishing TCP connections to the peer. If a BGP router 

has multiple links to a peer, when the source interface fails, BGP has to reestablish TCP connections, 

causing network oscillation. Therefore, it is recommended to use a loopback interface as the source 

interface to enhance stability of BGP connections. 

Follow these steps to specify the source interface of TCP connections: 

Enter system view 

— 

Enter BGP view 

bgp as-number 

— 

Specify the source interface for 
establishing TCP connections 
to a peer or peer group 

peer { group-name | 
ip-address } 
connect-interface 
interface-type 
interface-number 

Required 

By default, BGP uses the 
outbound interface of the best 
route to the BGP peer/peer group 
as the source interface for 
establishing a TCP connection to 
the peer/peer group. 

 

To establish multiple BGP connections between two routers, you need to specify on the local router the 

source interface for establishing TCP connections to each peer; otherwise, the local BGP router may 

fail to establish TCP connections to a peer when using the outbound interface of the best route to the 

peer as the source interface. 

 

In general, direct physical links should be available between eBGP peers. If not, you can use the peer 

ebgp-max-hop command to establish a TCP connection over multiple hops between two peers.  

Follow these steps to allow establishment of eBGP connection to a non directly connected peer/peer 

group: 

Enter system view 

— 

Enter BGP view 

bgp as-number 

—