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Cisco documentation shows that the side of the connection with the route blocking, is configured for orf receive. The other side of the connection is configured for send. This is the way i configured the routers and it works. E.G.(r1 - send | r4 - receive)

The SG is configured for the opposite (R1 - receive | R4 - send).

I'm confused at which is the right way and why they both work.

router bgp 200

 no synchronization

 bgp router-id 150.1.4.4

 bgp log-neighbor-changes

 neighbor 130.1.45.5 remote-as 200

 neighbor 130.1.124.1 remote-as 100

 neighbor 130.1.124.1 capability orf prefix-list receive

 neighbor 130.1.124.1 prefix-list BGP-FROM-R1 in

 neighbor 150.1.3.3 remote-as 200

 no auto-summary

Rack1R4#sh ip bgp       

BGP table version is 3, local router ID is 150.1.4.4

Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,

              r RIB-failure, S Stale

Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path

*> 28.119.16.0/24   130.1.124.1                            0 100 54 i

*> 28.119.17.0/24   130.1.124.1                            0 100 54 i

jguagliata:

Cisco documentation shows that the side of the connection with the route blocking, is configured for orf receive. The other side of the connection is configured for send. This is the way i configured the routers and it works. E.G.(r1 - send | r4 - receive)

The SG is configured for the opposite (R1 - receive | R4 - send).

I'm confused at which is the right way and why they both work.

SG has the correct way to apply orf. Here is the sample from the Cisco DoC

http://www.cisco.com/en/US/docs/ios/iproute_bgp/command/reference/irg_bgp3.html#wp1105692

Router-A Configuration (Sender)

The following example creates an outbound route filter and configures Router-A (10.1.1.1) to advertise the filter to Router-B (172.16.1.2). An IP prefix list named FILTER is created to specify the 192.168.1.0/24 subnet for outbound route filtering. The ORF send capability is configured on Router-A so that Router-A can advertise the outbound route filter to Router-B.

ip prefix-list FILTER seq 10 permit 192.168.1.0/24 

!

router bgp 100

 address-family ipv4 unicast 

 neighbor 172.16.1.2 remote-as 200

 neighbor 172.16.1.2 ebgp-multihop 

 neighbor 172.16.1.2 capability orf prefix-list send

 neighbor 172.16.1.2 prefix-list FILTER in

 exit 

Router-B Configuration (Receiver)

The following example configures Router-B to advertise the ORF receive capability to Router-A. Router-B will install the outbound route filter, defined in the FILTER prefix list, after ORF capabilities have been exchanged. An inbound soft reset is initiated on Router-B at the end of this configuration to activate the outbound route filter.

router bgp 200

 address-family ipv4 unicast 

 neighbor 10.1.1.1 remote-as 100

 neighbor 10.1.1.1 ebgp-multihop 255

 neighbor 10.1.1.1 capability orf prefix-list receive

 end 

clear ip bgp 10.1.1.1 in prefix-filter

This is the cisco doc i was reading. It has it the opposite. The confusing part for me, is it works with the send and receive either way.

http://www.cisco.com/en/US/docs/ios/12_2t/12_2t11/feature/guide/ft11borf.html#wp1036826

you apply a prefix list filter inbound on a neighbor to block certain prefixes, ORF sends / advertises that prefix list to that neighbor which recieves it and applies the prefix-list outbound, therefore no longer advertising the blocked prefixes.