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Multiple eBGP session between 2 Routers ,is it possible ?

Level 1
Level 1

1- As per the great book "Internet Routing Architecture" by Bassam Halabi that it is possible to have multiple eBGP session between 2 routers (page 212-213 , Balancing between 2 router sharing multiple path) .

2- On the other hand , the BGP RFC 1171 indicate

in para 6.8 page 28 (Connection collision

detection) that the router should not allow

more than one incoming BGP session with same "BGP Identifier" (BGP indentifier is part of the Open

Message ) .

3- Knowing that Cisco set "BGP Identifier" as

the Router ID (RID) . A RID is the Highest IP address or the highest Loopback address so

The 2 EBGP session will have the same "BGP identifier" .

4- From (2) and (3) , it is not possible to

have multile eBGP session between 2 routers .

5- (4) above contradict with (1) , what i am

missing ? Could it be that Cisco is not 100%

compliant with the RFC ??


1 Reply 1

Community Manager
Community Manager

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