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hi,

i read through about ORF at http://www.cisco.com/en/US/docs/ios/12_2t/12_2t11/feature/guide/ft11borf.html. From the question, it stated clearly R1 should send only the following prefixes to R4.

my understanding is R1 is only allow to send at ORF command. thus, the configuration shall look like below

Rack1R1# sh run | s router bgp
router bgp 65178
 no synchronization
 bgp router-id 150.1.1.1
 bgp log-neighbor-changes
 bgp confederation identifier 100
 bgp confederation peers 65026
 neighbor 130.1.17.7 remote-as 65178
 neighbor 130.1.124.2 remote-as 65026
 neighbor 130.1.124.2 capability orf prefix-list send
 neighbor 130.1.124.4 remote-as 200
 no auto-summary

But why at the solution guide was the other way round?

 

The router that is sending the update is upstream, and is therefore the router receiving the prefix-list used for outbound filtering.  For example if you are sending me routes A, B, and C, but I want to use ORF so that you only send me B and C.  I create a prefix list that permits B and C, and send the prefix list to you.  You receive the prefix list, use it as an outbound filter, and only allow prefixes B and C to be sent to me.

HTH,



neoflix wrote:

hi,

i read through about ORF at http://www.cisco.com/en/US/docs/ios/12_2t/12_2t11/feature/guide/ft11borf.html. From the question, it stated clearly R1 should send only the following prefixes to R4.

my understanding is R1 is only allow to send at ORF command. thus, the configuration shall look like below

Rack1R1# sh run | s router bgp
router bgp 65178
 no synchronization
 bgp router-id 150.1.1.1
 bgp log-neighbor-changes
 bgp confederation identifier 100
 bgp confederation peers 65026
 neighbor 130.1.17.7 remote-as 65178
 neighbor 130.1.124.2 remote-as 65026
 neighbor 130.1.124.2 capability orf prefix-list send
 neighbor 130.1.124.4 remote-as 200
 no auto-summary

But why at the solution guide was the other way round?

 

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thank you Brian for the clarification.

 

cheers